What is the best drug for allergies. Antihistamines: myths and reality
Medicines for the treatment of allergies are taken for a long time, so they must be absolutely safe and have a minimum amount. side effects. Among all antiallergic drugs, these are 4th generation antihistamines. Medicines of this group exist relatively recently, but due to their effectiveness, they are widely introduced throughout the world.
Modern antihistamines
Allergy develops due to the activation of type 1 histamine receptors (H1). Modern drugs of the 4th generation block these receptors, eliminating the symptoms of the disease. It is important that the drugs act selectively, that is, they do not affect type 2 and 3 receptors, which is the reason for the absence of side effects.
With the approach of spring and summer, the number of patients who need antiallergic therapy is increasing. Note that taking antihistamines a few days before contact with the allergen prevents the development and facilitates the course of the disease in the future. Because no matter how good the drug is, it has a cumulative effect. That is, with regular use, the best result is noted.
Modern 4th generation antihistamines are a small group of substances. However, pharmacological companies are actively combining antihistamines with other aids, thus obtaining tens various medicines.
Desloratadine
Desloratadine is the active metabolite of loratadine. The drug is available in the form of coated tablets and syrup. Desloratadine is used in children from 1 year old in the form of syrup and from 12 years old - in tablet form. However, the syrup cannot be used for fructose intolerance.
Desloratadine begins to act 30 minutes after ingestion, and its effect persists for a day. This is very convenient, as the patient can take a pill in the morning and the allergy symptoms will go away for the whole day. However, desloratadine, unlike loratadine, is contraindicated in pregnancy.
The antihistamine drug desloratadine does not have a toxic effect and does not affect the central nervous system. After taking the tablets, the patient does not experience drowsiness, which is characteristic of other generations of antihistamines. Trade names for desloratadine:
- Lordestin;
- NeoClaritin;
- Allergostop;
- Erius.
Levocetirizine
Levocetirizine is a histamine antagonist. It attaches to H1 receptors, preventing their interaction with allergy mediators. As a result, vascular permeability decreases, mucosal edema disappears, skin rashes and other manifestations of an allergic reaction are eliminated.
Levocetirizine acts in half of the patients 10-15 minutes after administration, and in the rest - after 30-60 minutes. The effect lasts for 24 hours, that is, the drug is prescribed 1 time per day. Take medicines with levocetirizine chronic pathology can be no more than 18 months. The drug is contraindicated in children under 6 years of age, pregnant women and during lactation.
Pharmacological preparations with levocetirizine:
- Caeser;
- Glenset;
- Suprastinex.
Fexofenadine
Fexofenadine is a metabolite of terfenadine. The drug is devoid of cardiotoxic action, which leads to the absence of complications from of cardio-vascular system. It is used for chronic allergic pathologies. The contraindication for use is childhood(up to 6 years), pregnancy and lactation.
Fexofenadine, like all modern antihistamines, is prescribed once a day. You can take it for several months, that is, the entire period of seasonal allergies. The drug does not cause drowsiness and does not affect the central nervous system.
In pharmacies, you can buy the following drugs with fexofenadine:
- Telfast;
- Feksadin;
- Fexofast.
Despite the fact that the list is not numerous, modern antihistamines are indispensable in the treatment of allergies. Perhaps in the future, based on these substances, new drugs will be invented that are more effective and allow you to permanently get rid of hypersensitivity organism to a number of factors.
Catad_tema Allergology - Articles
Antihistamines: myths and reality
"EFFICIENT PHARMACOTHERAPY"; No. 5; 2014; pp. 50-56.
T.G. Fedoskova
SSC Institute of Immunology, FMBA of Russia, Moscow
The main drugs that affect the symptoms of inflammation and control the course of diseases of allergic and non-allergic origin include antihistamines.
The article analyzes the debatable points regarding the experience of using modern antihistamines, as well as some of their main characteristics. This will allow a differentiated approach to the choice of the optimal drug in the complex therapy of various diseases.
Keywords: antihistamines, allergic diseases, cetirizine, Cetrin
ANTIHISTAMINES: MYTHS AND REALITY
T.G. Fedoskova
State Science Center Institute of Immunology, Federal Medical and Biological Agency, Moscow
Antihistamines belong to main drugs influencing symptoms of inflammation and controlling course of both of allergic and non-allergic diseases. In this paper debatable issues regarding experience of using current antihistamines as well as some of their characteristics are analyzed. It may let to make a differential choice to administer appropriate drugs for a combination therapy of different diseases.
key words: antihistamines, allergic diseases, cetirizine, Cetrine
Type 1 antihistamines (H1-AHP), or type 1 histamine receptor antagonists, have been widely and successfully used in clinical practice for more than 70 years. They are used as part of the symptomatic and basic therapy of allergic and pseudo-allergic reactions, complex treatment acute and chronic infectious diseases of various origins, as a premedication during invasive and radiopaque examinations, surgical interventions, to prevent the side effects of vaccination, etc. In other words, H 1 -AHP is advisable to use in conditions caused by the release of active inflammatory mediators of a specific and non-specific nature, the main of which is histamine.
Histamine has a wide spectrum biological activity realized by activation of cell surface specific receptors. The main depot of histamine in the tissues are mast cells, in the blood - basophils. It is also present in platelets, gastric mucosa, endothelial cells, and brain neurons. Histamine has a pronounced hypotensive action and is an important biochemical mediator in all clinical symptoms of inflammation of various origins. That is why antagonists of this mediator remain the most popular pharmacological agents.
In 1966, the heterogeneity of histamine receptors was proven. Currently, 4 types of histamine receptors are known - H 1 , H 2 , H 3 , H 4 belonging to the superfamily of receptors associated with G-proteins (G-protein-coupled receptors -GPCRs). Stimulation of H 1 receptors leads to the release of histamine and the realization of inflammation symptoms, mainly of allergic origin. Activation of H 2 receptors increases secretion gastric juice and its acidity. H3 receptors are predominantly present in the organs of the central nervous system (CNS). They perform the function of histamine-sensitive presynaptic receptors in the brain, regulate the synthesis of histamine from presynaptic nerve endings. Recently identified new class histamine receptors, expressed mainly on monocytes and granulocytes, - H 4 . These receptors are present in bone marrow, thymus, spleen, lungs, liver, intestines. The mechanism of action of H 1 -AHP is based on reversible competitive inhibition of histamine H 1 receptors: they prevent or minimize inflammatory reactions, preventing the development of histamine-induced effects, and their effectiveness is due to the ability to competitively inhibit the effect of histamine on the loci of specific H 1 receptor zones in the effector structures of tissues.
Currently, over 150 types of antihistamines are registered in Russia. These are not only H 1 -AGP, but also drugs that increase the ability of blood serum to bind histamine, as well as drugs that inhibit the release of histamine from mast cells. Due to the variety of antihistamines, it is quite difficult to make a choice between them for their most effective and rational use in specific clinical cases. In this regard, there are debatable points, and often myths are born about the use of H 1 -AHP, which are widely used in clinical practice. In the domestic literature, there are many works on this topic, however, there is no consensus on the clinical use of these drugs (PM).
The myth of three generations of antihistamines
Many are mistaken in thinking that there are three generations of antihistamines. Some pharmaceutical companies represent new drugs that have appeared on the pharmaceutical market, such as third-generation AGPs - the latest - generation. Attempts were made to classify metabolites and stereoisomers of modern AGPs to the third generation. Currently, these drugs are considered to be second-generation antihistamines, since there is no significant difference between them and previous second-generation drugs. According to the Consensus on Antihistamines, it was decided to reserve the name "third generation" to denote future synthesized antihistamines, which are likely to differ from known compounds in a number of key characteristics.
There are many differences between first and second generation AGPs. This is primarily the presence or absence of a sedative effect. A sedative effect when taking first-generation antihistamines is subjectively noted by 40-80% of patients. Its absence in individual patients does not exclude the objective negative effect of these drugs on cognitive functions, which patients may not complain about (the ability to drive a car, learn, etc.). Dysfunction of the central nervous system is observed even with the use of minimal doses of these drugs. The effect of first-generation antihistamines on the central nervous system is the same as when using alcohol and sedatives (benzodiazepines, etc.).
Second-generation drugs practically do not penetrate the blood-brain barrier, so they do not reduce the mental and physical activity of patients. In addition, first and second generation antihistamines differ in the presence or absence of side effects associated with stimulation of another type of receptor, duration of action, and development of addiction.
The first AGPs - phenbenzamine (Antergan), pyrilamine maleate (Neo-Antergan) began to be used as early as 1942. Subsequently, new antihistamines have appeared for use in clinical practice. Until the 1970s Dozens of compounds belonging to this group of drugs have been synthesized.
On the one hand, a large clinical experience has been accumulated in the use of first-generation antihistamines, on the other hand, these drugs have not undergone expert examination in clinical research that meet modern requirements of evidence-based medicine.
Comparative characteristics AGP of the first and second generations is presented in Table. one .
Table 1.
Comparative characteristics of AGP of the first and second generations
| Properties | First generation | Second generation |
| Sedation and effects on cognition | Yes (in minimal doses) | No (in therapeutic doses) |
| Selectivity for H 1 receptors | Not | Yes |
| Pharmacokinetic studies | Few | Many |
| Pharmacodynamic studies | Few | Many |
| Scientific studies of various doses | Not | Yes |
| Studies in newborns, children, elderly patients | Not | Yes |
| Use in pregnant women | FDA Category B (diphenhydramine, chlorpheniramine), Category C (hydroxyzine, ketotifen) | FDA Category B (loratadine, cetirizine, levocetirizine), Category C (desloratadine, azelastine, fexofenadine, olopatadine) |
Note. FDA (US Food and Drug Administration) - Food and Drug Administration (USA). Category B - no teratogenic effect of the drug was detected. Category C - studies have not been conducted.
Since 1977, the pharmaceutical market has been replenished with new H 1 -AHPs, which have clear advantages over first-generation drugs and meet modern requirements for AGPs set out in the EAACI (European Academy of Allergology and Clinical Immunology) consensus documents.
The myth about the benefits of the sedative effect of first-generation antihistamines
Even with regard to some of the side effects of first-generation antihistamines, there are misconceptions. The sedative effect of first-generation H1-HPA is associated with the myth that their use is preferable in the treatment of patients with concomitant insomnia, and if this effect is undesirable, it can be leveled by using the drug at night. At the same time, it should be remembered that first-generation antihistamines inhibit the phase of REM sleep, due to which the physiological process of sleep is disturbed, and there is no complete processing of information in sleep. Their use may cause respiratory failure, heart rate which increases the risk of developing sleep apnea. In addition, in some cases, the use of high doses of these drugs contributes to the development of paradoxical excitation, which also negatively affects the quality of sleep. It is necessary to take into account the difference in the duration of the preservation of the antiallergic effect (1.5-6 hours) and the sedative effect (24 hours), as well as the fact that prolonged sedation is accompanied by cognitive impairment.
The presence of pronounced sedative properties debunks the myth of the expediency of using H 1 -AHP of the first generation in elderly patients who use these drugs, guided by the prevailing stereotypes of habitual self-treatment, as well as the recommendations of doctors who are not sufficiently informed about pharmacological properties drugs and contraindications to their use. Due to the lack of selectivity of effects on alpha-adrenergic receptors, muscarinic, serotonin, bradykinin and other receptors, a contraindication to the appointment of these drugs is the presence of diseases that are quite common among the elderly patients - glaucoma, benign hyperplasia prostate, bronchial asthma, chronic obstructive pulmonary disease, etc. .
The myth about the absence of a place in clinical practice for first-generation antihistamines
Despite the fact that first-generation H1-AHP (most of them developed in the middle of the last century) are capable of causing known side effects, they are still widely used in clinical practice today. Therefore, the myth that with the advent of the new generation of AHD there is no place left for the previous generation of AHD is invalid. The H 1 -AGP of the first generation has one indisputable advantage - the presence of injectable forms that are indispensable in providing emergency assistance, premedication before carrying out some types diagnostic examination, surgical interventions etc. In addition, some drugs have an antiemetic effect, reduce the condition increased anxiety, effective in motion sickness. An additional anticholinergic effect of a number of drugs of this group is manifested in a significant reduction in itching and skin rashes with itchy dermatoses, acute allergic and toxic reactions to food products, medicines, insect bites and stings. However, it is necessary to prescribe these drugs with strict consideration of indications, contraindications, severity clinical symptoms, age, therapeutic dosages, side effects. The presence of pronounced side effects and the imperfection of the first generation H 1 -AGP contributed to the development of new second generation antihistamine drugs. The main directions of improvement of drugs were the increase in selectivity and specificity, the elimination of sedation and tolerance to the drug (tachyphylaxis).
Modern H 1 -AGP of the second generation have the ability to selectively affect H 1 receptors, do not block them, but, being antagonists, they transfer them to an "inactive" state without violating their physiological properties, have a pronounced anti-allergic effect, a rapid clinical effect, act long (24 hours), do not cause tachyphylaxis. These drugs practically do not penetrate the blood-brain barrier, therefore, do not cause a sedative effect, cognitive impairment.
Modern H 1 -AGP of the second generation have a significant anti-allergic effect - they stabilize the membrane of mast cells, suppress the release of interleukin-8 induced by eosinophils, granulocyte-macrophage colony-stimulating factor (Granulocyte Macrophage Colony-Stimulating Factor. GM-CSF) and soluble intercellular adhesion molecule 1 (Soluble Intercellular Adhesion Molecule-1, sICAM-1) from epithelial cells, which contributes to greater efficiency compared to first-generation H1-AHP during basic therapy allergic diseases, in the genesis of which mediators of the late phase play a significant role allergic inflammation.
In addition, an important characteristic of second-generation H1-AHP is their ability to provide an additional anti-inflammatory effect by inhibiting the chemotaxis of eosinophils and neutrophilic granulocytes, reducing the expression of adhesion molecules (ICAM-1) on endothelial cells, inhibiting IgE-dependent platelet activation, and releasing cytotoxic mediators. Many doctors do not pay due attention to this, however, the listed properties make it possible to use such drugs for inflammation not only of an allergic nature, but also of an infectious origin.
The myth of the same safety of all second-generation AHDs
There is a myth among physicians that all second-generation H1-HPAs are similar in their safety. However, in this group of drugs there are differences associated with the peculiarity of their metabolism. They may depend on the variability in the expression of the CYP3A4 enzyme of the liver cytochrome P 450 system. Such variability may be due to genetic factors, diseases of the hepatobiliary system, simultaneous administration of a number of drugs (macrolide antibiotics, some antimycotic, antiviral drugs, antidepressants, etc.), products (grapefruit) or alcohol that have an inhibitory effect on the oxygenase activity of the CYP3A4 cytochrome P450 system.
Among the H1-AGP of the second generation, there are:
Rice. one. Features of the metabolism of H 1 -AGP of the second generation
The advantages of active metabolites, the intake of which is not accompanied by an additional burden on the liver, are obvious: the speed and predictability of the development of the effect, the possibility of joint administration with various drugs and foods that are metabolized with the participation of cytochrome P450.
The myth of more high efficiency each new AGP
The myth that the new H1-AGP agents that have appeared in recent years are obviously more effective than the previous ones has also not been confirmed. The works of foreign authors indicate that second-generation H1-AHP, for example, cetirizine, have a more pronounced antihistamine activity than second-generation drugs that appeared much later (Fig. 2).
Rice. 2. Comparative antihistamine activity of cetirizine and desloratadine in terms of their effect on skin reaction caused by the introduction of histamine, within 24 hours 
It should be noted that among the H 1 -AGP of the second generation, researchers assign a special place to cetirizine. Developed in 1987, it was the first original highly selective H1 receptor antagonist based on the pharmacologically active metabolite of the previously known first-generation antihistamine, hydroxyzine. To date, cetirizine remains a kind of standard of antihistamine and antiallergic action, used for comparison in the development of the latest antihistamine and antiallergic drugs. There is an opinion that cetirizine is one of the most effective antihistamine H 1 drugs, it has been used more often in clinical trials, the drug is preferable for patients who respond poorly to therapy with other antihistamines.
The high antihistamine activity of cetirizine is due to the degree of its affinity for H 1 receptors, which is higher than that of loratadine. It should also be noted the significant specificity of the drug, since even at high concentrations it does not have a blocking effect on serotonin (5-HT 2), dopamine (D 2), M-cholinergic receptors and alpha-1-adrenergic receptors.
Cetirizine meets all the requirements for modern second generation antihistamines and has a number of features. Among all known antihistamines, the active metabolite cetirizine has the smallest volume of distribution (0.56 l/kg) and provides full employment of H 1 receptors and the highest antihistamine effect. The drug is characterized by a high ability to penetrate the skin. 24 hours after taking a single dose, the concentration of cetirizine in the skin is equal to or greater than the concentration of its content in the blood. At the same time, after a course of treatment, the therapeutic effect persists for up to 3 days. The pronounced antihistamine activity of cetirizine favorably distinguishes it among modern antihistamines (Fig. 3).
Rice. 3. Efficacy of a single dose of second-generation H 1 -AHP in suppressing histamine-induced wheal over 24 hours in healthy men 
The myth about the high cost of all modern AGPs
Any chronic illness not immediately amenable to even adequate therapy. As you know, insufficient control over the symptoms of any chronic inflammation leads not only to a deterioration in the patient's well-being, but also to an increase in the total cost of treatment due to an increase in the need for drug therapy. The selected drug should have the most effective therapeutic effect and be affordable. Physicians who remain committed to prescribing first-generation H1-AHP explain their choice by referring to yet another myth that all second-generation antihistamines are much more expensive than first-generation drugs. However, in addition to the original drugs on the pharmaceutical market, there are generics, the cost of which is lower. For example, at present, 13 generics are registered from cetirizine drugs in addition to the original one (Zyrtec). The results of pharmacoeconomic analysis presented in Table. 2, testify to the economic feasibility of using Cetrin, a modern second-generation AGP.
Table 2.
Results of comparative pharmacoeconomic characteristics of H1-AGP of the first and second generations
| A drug | Suprastin 25 mg № 20 | Diazolin 100 mg №10 | Tavegil 1 mg № 20 | Zyrtec 10 mg No. 7 | Cetrin 10 mg № 20 |
| Average market value of 1 pack | 120 rub. | 50 rub. | 180 rub. | 225 rub. | 160 rub. |
| Multiplicity of reception | 3 r/day | 2 r / day | 2 r / day | 1 r / day | 1 r / day |
| The cost of 1 day of therapy | 18 rub. | 10 rub. | 18 rub. | 32 rub. | 8 rub. |
| Cost of 10 days of therapy | 180 rub. | 100 rub. | 180 rub. | 320 rub. | 80 rub. |
The myth of same efficiency all generics
The question of the interchangeability of generics is relevant when choosing the optimal modern antihistamine drug. Due to the variety of generics on the market pharmacological agents, a myth arose that all generics act approximately the same, so you can choose any, focusing primarily on the price.
Meanwhile, generics differ from each other, and not only pharmacoeconomic characteristics. The stability of the therapeutic effect and the therapeutic activity of the reproduced drug are determined by the features of the technology, packaging, quality of active substances and excipients. The quality of the active substances of drugs from different manufacturers can vary significantly. Any change in the composition of excipients can contribute to a decrease in bioavailability and the occurrence of side effects, including hyperergic reactions of various nature (toxic, etc.). Generic must be safe to use and equivalent original drug. Two medicinal products are considered to be bioequivalent if they are pharmaceutically equivalent, have the same bioavailability and, when administered at the same dose, are similar, providing adequate efficacy and safety. According to the recommendations of the World Health Organization, the bioequivalence of a generic should be determined in relation to the officially registered original drug. The study of bioequivalence is one of the stages in the study of therapeutic equivalence. The FDA (Food and Drug Administration - Food and Drug Administration (USA)) annually publishes and publishes the "Orange Book" with a list of drugs that are considered therapeutically equivalent to the original. So any doctor can do optimal choice safe antihistamine drug, taking into account all the possible characteristics of these drugs.
One of the highly effective generics of cetirizine is Cetrin. The drug acts quickly, for a long time, has a good safety profile. Cetrin is practically not metabolized in the body, the maximum concentration in serum is reached one hour after ingestion, with prolonged use it does not accumulate in the body. Cetrin is available in 10 mg tablets, indicated for adults and children from 6 years of age. Cetrin is completely bioequivalent to the original drug (Fig. 4).
Rice. 4. The average dynamics of the concentration of cetirizine after taking the compared drugs 
Cetrin is successfully used as part of the basic therapy of patients with allergic rhinitis who are sensitized to pollen and household allergens, allergic rhinitis associated with atopic bronchial asthma, allergic conjunctivitis, urticaria, including chronic idiopathic , itchy allergic dermatoses, angioedema, and also as symptomatic therapy for acute viral infections in patients with atopy. When comparing the performance indicators of cetirizine generics in patients with chronic urticaria, the best results were noted with the use of Cetrin (Fig. 5).
Rice. five. Comparative evaluation of the clinical efficacy of cetirizine preparations in patients with chronic urticaria 
Domestic and foreign experience in the use of Cetrin indicates its high therapeutic efficacy in clinical situations where the use of second-generation H 1 antihistamines is indicated.
Thus, when choosing the optimal H 1 -antihistamine drug from all drugs on the pharmaceutical market, one should not be based on myths, but on selection criteria that include maintaining a reasonable balance between efficacy, safety and availability, the presence of a convincing evidence base, High Quality production.
BIBLIOGRAPHY:
1. Luss L.V. The choice of antihistamines in the treatment of allergic and pseudo-allergic reactions // Russian Allergological Journal. 2009. No. 1. S. 78-84.
2. Gushchin I.S. Potential of antiallergic activity and clinical efficacy of H1-antagonists // Allergology. 2003. No. 1. C. 78-84.
3. Takeshita K., Sakai K., Bacon K.B., Gantner F. Critical role of histamine H4 receptor in leukotriene B4 production and mast cell-dependent neutrophil recruitment induced by zymosan in vivo // J. Pharmacol. Exp. Ther. 2003 Vol. 307. No. 3. P. 1072-1078.
4. Gushchin I.S. Diversity of the antiallergic action of cetirizine // Russian Allergological Journal. 2006. No. 4. S. 33.
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Medicine does not stand still, its development reaches ever greater heights, and we are talking not only about treatment serious illnesses. Even the simplest ailments can cause a large number of problems, and their treatment is not so simple. In this article, we will talk about the treatment of allergies and fourth-generation drugs.
It's no secret that so many allergy medications have many side effects and do not cope with the symptoms as well as we would like. Antihistamines of the 4th generation destroy all ideas about the treatment of allergies. These are highly effective drugs that not only cope well with allergy symptoms, but are able to treat it for a long time without causing side effects, the most common of which are drowsiness and effects on the heart.
Types of allergic reactions and their manifestations
Allergic reactions can be both overt and covert. This is especially felt in children, when mommy cannot determine what is bothering the baby. The main symptoms of allergic reactions:
Shortness of breath and bronchospasm
heartbeat
Diarrhea, bloating
Mucous edema (eyes, nose, lips, throat)
Swelling skin, rash, blisters, sores
Itching of the skin
Profuse lacrimation
Clear discharge from the nose (discharge of yellow, green color, with impurities of blood indicates infectious diseases, in case of allergy - this is only a reaction of the mucous membrane to an external irritant)
These symptoms can occur with various types of allergies: food, dust, pollen, wool or particles of animal skin. If you notice any symptom in yourself or your children, you should take action immediately, as the development of an acute allergic reaction can lead to life threatening states: , anaphylactic shock, angioedema.
First aid for the development of an allergic reaction:
Avoid contact with the allergen. This is the only way that will allow you to avoid allergies.
Don't stress your body: if you know you're having a reaction to a food, don't under any circumstances eat it, and the same goes for animals.
Consult with an allergist about therapy. Only a specialist can competently draw up a course of treatment and prescribe a list of drugs that will protect you and your children from allergic reactions in any setting. Currently, there are a huge number of drugs that can cope with allergies quickly and effectively.
The development of drugs for allergies
1st generation drugs. These include all sedative drugs, that is, they invariably provoke drowsiness, reduce performance, and worsen visual acuity. They block histamine receptors, and quite well, but the effect lasts only a few hours, while the abundance of side effects does not allow them to be used by people who need concentration, for example, driving or at work. In addition, taking them in the morning, a person will be in a sleepy state all day, which also brings discomfort to life. These drugs include the well-known Suprastin, Tavegil, Diazolin and others. These drugs are prescribed in the treatment of bronchial asthma, as well as to relieve other allergy symptoms.
Medicines of the 2nd generation. They do not have a sedative effect, but they stimulate the work of the heart muscle. Therefore, they should not be used by people with diseases of the cardiovascular system. The most effective such drugs against skin rashes. These include Fenistil, Claritin, Zodak.
3rd generation drugs. This is the next step in the development of medicine for the treatment of allergies. They do an excellent job of treating allergies, including skin rashes, acute reactions and bronchial asthma. They have practically no contraindications, they can also be prescribed for the treatment of allergies in children. At the same time, they do not have side effects, like the previous two types of drugs. These drugs include Telfast, Cetrin, Zirtek.
This is the pinnacle in the treatment of allergic reactions. Most Effective modern drugs, which in a short time eliminate the symptoms of allergies, while acting for a long time. They block the production of histamine, reliably relieving a person of all possible manifestations allergic reaction. They do not affect the heart muscle, do not cause drowsiness, do not impair reaction and attention. However, such drugs have some contraindications, it is recommended to consult a doctor before use in children, the same applies to pregnant women. We will talk about the most popular drugs of this type further.
Modern drugs latest generation, list of trade names:
Erius Desloratadine. It is the successor to Loratadine, which was among the drugs of the previous generation. Desloratadine is effective for the treatment of acute allergic reactions, as well as for the treatment of seasonal manifestations of allergies. Quickly copes with unpleasant symptoms, such as skin itching, redness, swelling of mucous membranes, sneezing and coughing. It is used to treat allergies in children and adults. In the form of a syrup, it is prescribed for children under 12 years of age, in the form of tablets for older children and adults. Available under trade names Erius, Lordestin, NeoClaritin. The use of these drugs is contraindicated for pregnant women, but has no side effects, and the action continues throughout the day, while the effect occurs within half an hour after application.
Suprastinex Levocetirezin. Used for treatment various types allergic reactions. It also has no side effects, sedative properties are minimized. Patients with kidney disorders should use these drugs with caution, consulting a doctor is required. The effect occurs within two hours after the use of the drug, while one tablet per day is also enough to maintain the medical effect. Sometimes the application can be even less frequent: every other day, or even a couple of times a week. The treatment regimen is made by the doctor strictly individually. Available in the form of tablets Suprastinex, Caeser and others. Pregnant women are also contraindicated.
Telfast Fexofenadine. Very effective drug for the treatment of seasonal allergies, as it can be used very long time, while it does not affect the work of the heart muscle, as well as the central nervous system. Children under six years of age should not use it, as well as pregnant and lactating women. Produced in the form of tablets under the trade names Telfast, Feksadin. Before use, consultation with your doctor is required. The effect is achieved quickly and lasts long enough. Perfectly copes with allergic conjunctivitis, urticaria and swelling of the mucous membranes.
Allergy treatment should be taken seriously, as a few symptoms such as sneezing, itching or rashes can lead to serious consequences. If you pay attention to the symptoms in time and start complex therapy, it is possible complete cure provided that treatment was started on early term and all precautions are taken. The sooner you see an allergist, the more successful treatment and the best results you can expect.
Modern antihistamines: three steps to victory over allergies
M. Trofimov, Ph.D. honey. Sciences
The arrival of spring makes itself felt not only by the beginning of violent plant flowering, but also by an increase in the frequency of hay fever and other seasonal allergic diseases, and antiallergic drugs during this period become the subject of increased demand in pharmacies. However, drugs for the prevention and treatment of allergic reactions occupy one of the most important segments of the pharmaceutical market, regardless of the season, because the incidence of chronic year-round allergies is steadily growing. Those times have irretrievably sunk into oblivion when, operating with three or four drugs available and familiar from the Mashkovsky reference book, a doctor or pharmacy worker could live in peace, considering the problem of treating allergies solved. Now all (or almost all) achievements of world pharmacological science in this area are available to domestic specialists. And they are significant - today there are more than 60 monocomponent antihistamines for systemic use alone, not to mention their combinations and new drugs from other groups used to treat allergies - leukotriene receptor antagonists (montelukast, zafirlukast), 5-lipoxygenase inhibitors (zeliuton) , mast cell membrane stabilizers, antichemotactic agents, etc. With such an extensive therapeutic arsenal, the specialist inevitably faces the problem of optimal choice.
One class - different properties
Despite the emergence of new groups of antiallergic drugs, antagonists of allergy mediators are still most widely used, which, due to inertia, continue to be called antihistamines, or histamine blockers. It should be noted that this term is somewhat outdated, since it does not reflect the pharmacodynamic features of most new drugs that are antagonists not only of histamine, but also of other allergy mediators (serotonin, bradykinin, leukotrienes). Drugs created in recent decades can also have an additional effect on the processes of allergic inflammation.
However, the main mechanism of the antiallergic effect of this class of drugs remains the ability to competitively block histamine H1 receptors without a pronounced effect on H2 and H3 receptors. As is known, biological effects histamine are very diverse and depend on the point of application of this mediator. From the side respiratory system it can be bronchospasm, swelling of the nasal mucosa, hypersecretion; on the part of the skin - itching, hyperemia, bullous reaction; digestive tract and other internal organs - spasm of smooth muscles, intestinal colic, stimulation of gastric secretion; cardiovascular system - increased vascular wall permeability and capillary expansion, hypotension, cardiac arrhythmias. Wide spectrum the effects of histamine determines the expediency of using antihistamines in many diseases, primarily in urticaria, atopic dermatitis and bronchial asthma, seasonal and year-round allergic rhinitis and conjunctivitis, drug allergy etc. H1-blockers are not able to displace histamine from its association with receptors, since they interact only with free or released receptors. Accordingly, these drugs are most effective in preventing immediate allergic reactions, and in the case of an already developed reaction, they can only reduce its severity. Despite the advances in allergology, it is far from possible to identify a potential allergen in all patients, and the results of specific desensitization are not always satisfactory. Therefore, the use of antihistamines often remains the only way to make life easier for patients with severe atopic allergies.
To make it easier to navigate the sea of antihistamines, let's define the main "beacons". In the 2004 revision of the WHO ATC classification, according to chemical affiliation, six main groups of antihistamines for systemic use are distinguished (Fig. 1).
Picture 1. Antihistamines for systemic use
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For funds registered in Ukraine, trade names are given (highlighted in italics).
* available dosage forms allowed for non-prescription sale.
Peculiarities chemical structure determine some pharmacotherapeutic properties of drugs. Most ethanolamine derivatives are characterized by pronounced mholinolytic and sedative effects. Alkylamines are among the most active H1 receptor antagonists, while their sedative properties are usually weakly expressed; in some patients, they can cause an increase in the excitability of the nervous system. Most piperazine derivatives also show a mild sedative effect (except hydroxyzine). Cholinolytic properties of phenothiazines are similar to ethyleneamine derivatives. Phenothiazine drugs are often used as antiemetics. Piperazine derivatives are distinguished by high selectivity for H1 receptors in the absence or weak severity of anticholinergic properties and effects on the central nervous system.
Generation after generation
FROM clinical point In terms of view, it seems more important to isolate three generations of antihistamines, taking into account not so much the time of their creation as the presence of additional properties and pharmacodynamic features in them (Table 1). IN in general terms the differences between them can be characterized as follows. Preparations of the first generation act on peripheral and central histamine receptors, cause a sedative effect, and do not have an additional anti-allergic effect. Means of the second generation, unlike their predecessors, act only on peripheral H1-histamine receptors, do not have a sedative effect, and have a number of additional antiallergic effects. Unfortunately, some of them have a cardiotoxic effect. The fundamental difference between the last, third generation antihistamines is that they are active metabolites of II generation drugs, therefore, they are devoid of a negative effect on the heart.
Table 1. Representatives of new generations of antihistamines
The pharmacokinetic properties of "classic" and new antihistamines differ significantly. II generation drugs have a similar structure of the central part of the molecule; the features of absorption, distribution and excretion of each of them depend on the radicals or side chains attached to this central part. Modern antihistamines have a long duration of action (12-48 hours), which allows them to be prescribed 1-2 times a day, while most first-generation drugs have a short duration of action (4-12 hours) and require taking several times a day. The longer action of new generation antihistamines is due to the fact that they bind noncompetitively to H1 receptors, and the resulting ligand-receptor complexes dissociate very slowly. The maximum half-life, taking into account the formation of the active metabolite, has astemizole (10 or more days); it is able to inhibit skin reactions to histamine and allergens for 6-8 weeks. Second generation antihistamines are well absorbed from gastrointestinal tract. The maximum plasma concentration of the parent compound is usually observed after 1-3 hours, and the maximum concentration of the active metabolite, if any, after 0.5-2 hours. Simultaneous food intake affects their absorption in different ways: the absorption of astemizole decreases by 60%, the absorption of ebastine and loratadine increases, and the absorption of acrivastine, azelastine and cetirizine does not change.
The degree of affinity of "old" and new drugs for H1-histamine receptors is approximately the same. Therefore, the choice of drug may be determined by the cost of the course of treatment, taking into account the safety profile and clinical feasibility (the presence of additional antiallergic effects or other advantages in the drug).
Veterans will still serve
The first antihistamine drug (thymoxydiethylamine), for the creation of which one of its developers D. Bovet received the Nobel Prize in 1957, appeared on the market as early as 1937. From then until the early 1980s, more than 40 first-generation antihistamines entered the pharmaceutical market. Although the effectiveness of these drugs in the treatment of allergic diseases has been confirmed by many years of clinical practice and no one doubts, their value is significantly reduced by the presence of central action due to the ability to penetrate the blood-brain barrier due to lipophilic properties and electrostatic charge. The central effect is manifested by a sedative effect, drowsiness, a decrease in psychomotor activity, an increase in appetite, etc. Taking these drugs is contraindicated in persons whose work is related to potential danger or requires increased attention: drivers, pilots, operators. The sedative effect is enhanced by alcohol and other substances that depress the central nervous system (tranquilizers, antipsychotics, sedatives, etc.). In addition, many first-generation antihistamines have anticholinergic activity and can cause such negative effects as dry mouth, urination disorders, visual disturbances, etc. long-term use(tachyphylaxis).
Despite the shortcomings listed above, first-generation histamine blockers are still used today, mainly due to the known clinical efficacy at relatively low cost, the availability of forms for parenteral administration, and also simply due to clinical inertia. Currently, they are prescribed mainly for immediate allergic reactions (acute urticaria, anaphylactic or anaphylactoid shock, Quincke's edema, serum sickness, drug allergy, acute allergic reactions to food products), as well as for prophylactic purposes with the introduction of histamine liberators (tubocurarine).
Some first generation antihistamines may be useful in a number of atypical clinical situations not associated with allergies. For example, since drugs with an anticholinergic effect (promethazine, chloropyramine, pheniramine, chlorphenamine, diphenhydramine) have a “drying” effect on mucous membranes, they are often included in combined drugs for symptomatic treatment colds. The central action of the first generation drugs allows them to be used to suppress cough (diphenhydramine, alimemazine, promethazine), short-term correction of sleep disorders (diphenhydramine, doxylamine), prevent nausea and dizziness in case of air and motion sickness, Meniere's syndrome (meclozine), as well as to potentiate the effect analgesics in the composition of lytic mixtures (diphenhydramine, alimemazine, promethazine).
Caution and more caution
The beginning of the 1980s was marked by the appearance of a new generation of antihistamines (terfenadine, astemizole, loratadine), which, in terms of antiallergic activity, were comparable to the first generation drugs, but lacked a sedative effect. The advantages of second-generation antihistamines include high affinity for H1 receptors, no effect on choline and serotonin receptors, rapid onset and long duration of action, no interaction with alcohol and psychotropic drugs, no tachyphylaxis with long-term use, the presence of additional antiallergic effects (the ability to stabilize mast cell membranes, suppress the induced accumulation of eosinophils in respiratory tract etc.) and, accordingly, a wider range of indications for use (bronchial asthma, atopic dermatitis, hay fever, allergic rhinitis).
However, soon after their introduction into clinical practice, alarming reports appeared that some second-generation antihistamines (astemizole, terfenadine, and possibly ebastine) under certain circumstances can cause fatal arrhythmias associated with prolongation of the QT interval (torsade de pointes tachycardia). , or flutter-flicker of the ventricles) due to blocking of potassium ion channels that control the repolarization of myocardial membranes.
It was found that the therapeutic effect of second-generation antihistamines is almost entirely due to their active metabolites formed in the liver with the participation of enzymes of the cytochrome P450 system, and the negative effect on the electrical activity of the heart is caused by unchanged drugs. Accordingly, in case of an overdose, impaired liver function, or concomitant use of inhibitors of microsomal enzymes, the metabolism of the parent compounds slows down, and their concentration in the blood plasma increases, negatively affecting electrical activity myocardium. The likelihood of developing a cardiotoxic effect of these drugs increases with simultaneous administration with macrolides (erythromycin, oleandomycin, azithromycin, clarithromycin), antifungal agents of the azole group (ketoconazole and itraconazole), some antiarrhythmic drugs(quinidine, procainamide, disopyramide), antidepressants (fluoxetine, sertraline and paroxetine), when drinking grapefruit juice, as well as in patients with severe liver dysfunction and electrolyte imbalance. In fairness, it should be noted that only astemizole, terfenadine and experimentally - ebastine had a cardiotoxic effect, while other representatives of second-generation antihistamines have no such effect.
Of the second generation drugs, only cetirizine is not a “prodrug” metabolized in the body, since it is an active metabolite of hydroxyzine, devoid of its central action. Another distinctive feature cetirizine is the ability to easily penetrate the skin and accumulate in it in high concentrations, even after a single dose, which makes it the drug of choice in the treatment of urticaria and atopic dermatitis. Neither in experiment nor in clinical setting no arrhythmogenic effect was found in cetirizine.
The most modern
In connection with the identification of the mentioned “fly in the ointment” in the form of arrhythmogenic action of some new antihistamines, further efforts of scientists were concentrated on the development of drugs based on active metabolites, which, while retaining all the advantages of their predecessors, would at the same time be deprived of their cardiotoxic effect even when administered at high doses. These studies culminated in the creation of third-generation antihistamines. In addition to significant selectivity for peripheral H1 receptors, the absence of sedative and cardiotoxic effects, they have additional antiallergic effects: they inhibit the release of mediators of systemic allergic inflammation, including cytokines and chemokines (tryptase, leukotriene C4, prostaglandin D2, interleukins 3, 4 and 8, factor tumor necrosis TNF, granulocyte-macrophage colony-stimulating factor, RANTES), reduce the expression of adhesion molecules (including P-selectin and ICAM-1), suppress chemotaxis and activation of eosinophils and the formation of superoxide radical, reduce bronchial hyperreactivity and the severity of allergen-induced bronchospasm. The activity of metabolites can be 2-4 times higher than the parent compound (for the metabolites of acrivastine, ebastine and loratadine) or the same (for the metabolites of astemizole and ketotifen), and the half-life and duration of therapeutic action of some metabolites is much longer than that of the drug -predecessor (terfenadine and fexofenadine, ebastine and carebastin).
Therefore, the use of antihistamines preparations III generation is more justified in the long-term therapy of allergic diseases, in the genesis of which mediators of the late phase of allergic inflammation play a significant role: year-round allergic rhinitis, seasonal allergic rhinitis or rhinoconjunctivitis with a seasonal exacerbation duration of more than 2 weeks, chronic urticaria, atopic dermatitis, allergic contact dermatitis. Features of pharmacokinetics, a good safety profile and high clinical efficacy make third-generation drugs the most promising antihistamines at present.
Fexofenadine is a racemic mixture of two pharmacologically active isomers of the active metabolite of terfenadine. The antihistamine effect begins to appear 30 minutes after ingestion, the concentration in the blood reaches a maximum during the first hours, the duration of action is up to 24 hours. Clinical trials of fexofenadine have shown that even a two- and three-fold excess of the average therapeutic dose of the drug does not cause a sedative effect. Fexofenadine is not metabolized in the body, its pharmacokinetic profile does not change with impaired liver and kidney function. Along with maximum safety, fexofenadine demonstrates the ability to effectively eliminate the symptoms of seasonal allergic rhinitis and chronic idiopathic urticaria. Depending on the indications, it is prescribed in a dose of 120 or 180 mg 1 time per day, respectively.
Desloratadine is the active metabolite of loratadine, more than two and a half times more active than the parent substance. A wide range of anti-allergic and anti-inflammatory activity of desloratadine determines its high effectiveness in the treatment of various allergic diseases. nasal breathing with seasonal allergic rhinitis. The drug is also effective if allergic rhinitis is combined with atopic bronchial asthma. In patients with chronic idiopathic urticaria, a pronounced and persistent effect of desloratadine contributes to the rapid relief of symptoms and an improvement in the quality of life. The recommended daily dose is 5 mg. The half-life of desloratadine is 21-24 hours, which allows the drug to be administered once a day.
Carebastin is a carboxylated metabolite of ebastine. Excreted by the kidneys (60-70%) in the form of conjugates. The half-life of carebastin is 15–19 hours, the duration of the antihistamine effect is at least 24 hours. Carebastin, norastemizole and levocetirizine are not yet registered in Ukraine, but it is obvious that their entry into the Ukrainian pharmaceutical market is just a matter of time.
Literature
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Currently, in almost all pharmacies in different cities, you can find many allergy medicines, produced in many forms, from tablets to suspensions, ointments, gels and creams.
Below is a list of antiallergic drugs available in the form of tablets and drops:
- Allegra (Telfast) - the active ingredient that it contains is fexofenadine. This drug can not only block the level of histamine in the body, but also prevent its production. Most of all it is prescribed for frequent urticaria and seasonal allergies. His therapeutic effect persists for a whole day after the entire course of treatment. Doesn't cause addiction. In pharmacies, this drug is sold in the form of tablets. Allegra should not be taken by children under twelve years of age, pregnant women and during breastfeeding.
- Cetirizine - such a medicine is used to get rid of allergies and for its prevention. The result from it is achieved already twenty minutes after taking it and there are still three days left after the end of the course of treatment. After taking Cetirizine, a person is not tormented by drowsiness and mental and physical activity. In a pharmacy, you can buy it in the form of drops (it can also be called Zirtek, Zodak), in syrup (Cetrin, Zodak) and tablets - Cetirizine. For children, starting from the age of six months, they are used in the form of drops, from one year old - in the form of syrup, and from the age of six they can be taken in tablets. The dose should be selected only by a specialist and for each patient separately. Not to be taken by pregnant and breastfeeding women.
- Xyzal is antihistamine mainly prescribed to get rid of chronic and seasonal allergies, urticaria and itching of the skin. The effect of it appears 40 minutes after ingestion. Sold in a pharmacy in tablets or drops. Children of two years of age are prescribed drops, and from the age of 6 - tablets. The dose is chosen by the specialist, focusing on body weight and age. It is not allowed to be taken by expectant mothers, but it is acceptable when breastfeeding.
- Desloratadine - in another way it can be called Erius. Available in the form of tablets and syrup. In addition to anti-allergic properties, this drug also has anti-inflammatory properties. Perfectly cures seasonal allergies and chronic urticaria. While taking Desloratadine, your mouth may feel dry and headache. Like other drugs, children of two years of age are prescribed in the form of syrup, and from 6 years old - in tablets. Not recommended for pregnant and lactating women. It is also approved for use in life-threatening problems such as Quincke's edema and suffocation (bronchospasm).
Antihistamine ointments and gels, a list of these funds
The human skin is the largest organ, which first begins to give signals that occur inside the body from any adverse problems. It mainly appears various rashes in the form of blisters, red spots, etc., from which ointments and gels can perfectly help.
However, such drugs are unable to completely cure the allergy, but simply block its symptoms for a while.
All modern ointments and gels against allergies can be hormonal and non-hormonal, anti-inflammatory and combined.
Let's talk more about each group:
- Non-hormonal. Used to get rid of food allergies, insect bites. These include: Bepanten, D-panthenol, Pantoderm, Radevit, Videstim, Fenistil-gel.
- Hormonal remedies for allergies. These drugs include: Flucinar, Hydrocortisone ointment, Advantan, Elokon.
- Combined preparations: Triderm - available as an ointment or cream; Betamethasone (glucocorticosteroid); clotrimazole ( antifungal drug); Gentamicin in pharmacies is sold in the form of an ointment and is a broad-spectrum antibiotic.
From all of the above, it can be seen that at present there are a lot of ointments and gels against allergic reactions on the skin. Of all the ointments and gels of the new generation, only a specialist can choose the right one, depending on the state of health, skin sensitivity and other factors of the patient, which will really help, while not harming the body.
And you must also remember that ointments and gels from skin itching, red spots and other allergic reactions can only help well if they are used in combination with other antihistamines and, of course, in compliance with hypoallergenic conditions at home and at work.
The difference between new antiallergic drugs and old ones
Allergy medicines of the new generation differ from the old ones in that they are a prodrug. When they enter the body, they immediately begin to be metabolized - activated in the liver. The newest drugs don't have sedative action, and they do not have a negative effect on the performance of the cardiovascular system.
New antiallergic drugs perfectly fight various types of allergies, as well as different types childhood dermatitis and dermatitis in people who suffer from heart disease. It is also the new generation drugs that are mainly prescribed for people with serious professions, for example, surgeons, drivers, pilots.
Medicines remove all allergy symptoms. At a normal dosage, they are not able to increase drowsiness, reduce mental capacity, but with increased headaches, dizziness, heart rhythm disturbances can be observed.
The same differences exist for topical preparations. New allergy remedies for lubricating the skin differ from the old ones in that they very rarely lead to side effects, most of all they are hormonal drugs.
And of course, new ointments and gels against allergic reactions on the skin are allowed to be used by children from the age of 4 months, pregnant women and during breastfeeding, which cannot be done with older generation drugs. Some ointments or gels can be used for a long time.
Composition and therapeutic effect
New generation allergy remedies contain special H1-histamine receptors that block excess histamine in the body. By this, histamine is unable to bind to the receptors. From this, all the phenomena of allergies subside, that is, the rash on the skin begins to become white color, puffiness, itching decreases, it becomes easier to breathe through the nose, the phenomena of conjunctivitis decrease.
And also in modern means from allergies contain active ingredients for a single drug, these can be: fexofenadine, fluocinolone, acetonide, acetate, hydrocortisone, mometasone furoate, various corticosteroids, antifungal and antibacterial agents, various flavoring agents, and much more.
Useful video on the topic
Contraindications and side effects
As with any drug, modern antiallergic drugs also have several contraindications and side effects.
But they can only occur in case of a large overdose.
But despite all this, all side effects pass in a matter of days and are of a moderate nature when a person begins to take a normal dose of medication.
Let's talk about the most common side effects:
- constant desire to sleep;
- dizziness, headache;
- cardiopalmus;
- muscle pain;
- skin allergy, unbearable itching and sometimes Quincke's edema.
But there is only one contraindication for antiallergic drugs of the new generation - this is an excessive individual intolerance to the substances contained in each medicinal product against allergies or to its active ingredient. 
In addition to these described side effects and contraindications, no more have been identified. One of the biggest disadvantages in such drugs is the high cost. But still, in the latest generation of antiallergic drugs, the negative effect is at the lowest level.
For example, allergy pills and syrups do not form a cumulative effect, which means they are not harmful. human body and health in general, even with long-term use.
Modern remedies for urticaria
Basically, for the treatment of urticaria, new generation drugs come in the form of tablets, sprays, ointments, injections and drops. But still the most popular are tablets, ointments, gels for local use. IN modern tablets, ointments and gels against urticaria contain special H1 receptor blockers.
Therefore, often when the first signs of urticaria are detected, the doctor prescribes the latest drugs from allergies, in order to completely remove the symptoms of this disease, and improve the patient's well-being.
But, and if antihistamines did not help to cope with the problem, then the doctor prescribes treatment hormonal drugs to protect a person from dangerous consequences.
Often, doctors prescribe various sorbents, diuretic compounds that help rid the body of harmful allergens and neutralize the disease in a short time.
And if the urticaria arose due to nervous breakdown, then a person is prescribed a course with different sedatives. However, with such medicines movement coordination, attention and memory are disturbed, therefore at this time it is recommended not to drive a car.
So, in case of urticaria, in no case should you start taking various anti-allergic drugs on your own, it is still better to go straight to the hospital so that the doctor examines and chooses the right medicine and its dosage.
Features of use in asthma
As you know, bronchial asthma is caused due to the decomposition of mastocytes, that is, mast cells that emit a huge amount of histamine, which prevents this disease. Therefore, many doctors with bronchial asthma prescribe various anti-inflammatory and anti-allergic medications to protect mast cells from destruction. But, unfortunately, these drugs are not able to completely protect them.
In addition, the released histamine, on the contrary, increases inflammatory process in the bronchial tree. And only additionally prescribed antihistamines can completely remove the symptoms of bronchial asthma.
Them healing effect due to the fact that they are based on histamine receptors located in the smooth muscles of the bronchi and blood vessels of the microvasculature. This effect is considered the only way to reduce inflammation and swelling of the bronchial mucosa, as well as eliminate spasm.
While taking the newest antihistamines, it is worth remembering that they are not remedy. But they do an excellent job of stopping a developing problem. If a polyvalent allergy is detected, then the drugs are taken as a basic treatment for atopic bronchial asthma.
Appointment for children and the elderly
In our time, the latest medical drugs for allergic reactions are being used with great success to treat various kinds allergies, both in older people suffering from diseases of the heart and blood vessels, and in young children.
If the old generation drugs were allowed to be used by children only from the age of two, then the new generation drugs are taken from the age of four months. This can be explained by the fact that the new drugs contain more modern substances that do not irritate the mucous membranes, do not disturb the sensitivity of the skin and do not adversely affect the functioning of the heart.
The opinion of people who used this tool
Almost all people who have used the new generation of antihistamines say that this is just a salvation for the whole body. Since after taking such funds, the general well-being of the body improves, vigor is produced, it becomes easier to breathe. In a word, life with them becomes much better and happier, especially for those who suffer chronic form allergies.
Here are some users the latest tools from allergies, they speak positively only if, during their use, they still follow a special diet, otherwise they already do not work so well.
In addition, new allergy medications enable young children with frequent allergic reactions live peacefully and fully. At the same time, the daily dose of these drugs for a child is very small.
Pregnant women also have a positive effect on new-generation anti-allergy drugs, because even in such a difficult time, you can improve your well-being, which is so necessary for expectant mothers.
In conclusion, we can add that allergies have now become a very popular problem. Every year, a huge number of people with allergies come to the hospital, and most of all - these are young people. But thanks to the fact that latest technology growing every day, new medical preparations give an excellent opportunity to sick people to live freely, fully.
It is these remedies that not only remove all the causes of allergies, but also improve general state in general, without changing the performance of the heart and other vital important organs person. So take care of yourself and your health, because this is a huge value in our life, which is very easy to lose, but hard to return.
And, most importantly, do not self-medicate, not knowing the dosage for the drug, you can greatly harm the body, which you will regret throughout your life.