The category of mast cell membrane stabilizer drugs includes topical drugs - cromones, as well as systemic drugs with an auxiliary - antihistamine property, namely ketotifen.
The mechanism of action of these medications is that they are able to block the entry of calcium and chlorine ions into cells, as a result of which the allergy mediator (histamine) is stabilized and the membrane loses the ability to leave this cell. In addition, membrane stabilizers are able to prevent the release of other substances that are involved in the development of allergic phenomena.
What is this?
Mast cell membrane stabilizers - drugs that prevent the opening of calciumchannels and the penetration of calcium into mast cells. They block calcium-dependent degranulation of cells and the release of histamine from them - a factor that activates platelets, leukotrienes. They also reduce the manifestations of anaphylaxis and other biologically active substances that can induce inflammatory and allergic reactions. Stabilization of mast cell membranes is due to blockade of cAMP accumulation in them and inhibition of phosphodiesterase.
The main aspect of the antiallergic effect of mast cell membrane stabilizers is the increased perception of catecholamines by adrenergic receptors. In addition, such drugs have the property of blocking chloride channels and thus preventing depolarization of parasympathetic endings in the bronchi. They prevent cellular infiltration of the bronchial mucosa and inhibit delayed hypersensitivity reactions. Some of the drugs in this group have the ability to inhibit H1 receptors.
Medications eliminate swelling of the bronchial mucosa and prevent an increase in the tone of smooth muscles. The main indication for their use is the prevention of bronchial obstruction.
Effects
The effects of mast cell membrane stabilizer drugs are:
- decrease in excessive reactivity of mucous membranes (due to inhibition of release from mediators of allergic cell reactions);
- decrease in the activity of cells that are involved in the development of allergic reactions (eosinophils, macrophages, neutrophils and others);
- decrease in permeabilitymucous membranes - due to a decrease in swelling;
- decrease in the sensitivity of nerve receptors and subsequent blocking of the reflex narrowing of the bronchial lumen - bronchoconstriction.
What is the mechanism of action of mast cell membrane stabilizers?
Pharmacological properties
The use of drugs of this pharmacological group prevents the development of allergic phenomena (bronchospasm, swelling) when potential allergens penetrate the body, as well as when it is influenced by various provoking factors - physical activity, cold air and others.
Ketotifen is a mast cell membrane stabilizer. It, like cromones, reduces the increased activity of the respiratory tract in the form of a response to the ingestion of an allergen. In addition, it is a blocker of H1-histamine fibers, that is, it inhibits the progression of allergic processes.
This is the main mechanism of mast cell membrane stabilizers.
In general, membrane stabilizers with their regular long-term use reduce the frequency of exacerbation of chronic allergic diseases.
Cromones are used to prevent allergic rhinitis and conjunctivitis, bronchial asthma and the development of bronchospasm caused by the influence of provoking factors (exercise, cold air, etc.), as well as before potential contact with potential allergens. Among other things, the drugs of thispharmacological category are used in the complex treatment of bronchial asthma - in the form of one of the basic therapy medicines. To eliminate bronchospasm, these medical drugs are not used from this classification.
Ketotifen is referred to as a mast cell membrane stabilizer. It is used to prevent the atopic form of bronchial asthma, the treatment of atopic dermatitis, conjunctivitis and rhinitis of an allergic nature, chronic urticaria. The widespread use of this drug is significantly limited by its relatively low anti-allergic and anti-inflammatory activity, as well as pronounced side effects of 1st generation antihistamines, which are also characteristic of this drug.
Maximum effectiveness of cromones occurs approximately 14 days after their systematic use. The duration of such therapy should be 4 months or more. Cancel the medication gradually over the course of a week.
No addiction is observed when using it, there is also no decrease in the effectiveness of other medicines with their long-term use (tachyphylaxis symptoms). Are there contraindications for mast cell membrane stabilizers?
Contraindications
These funds are contraindicated in the development of asthma attacks. Also, they should not be used in the presence of asthmatic status or hypersensitivity to them.
Inhalation
When inhaledmethods of treatment with the use of cromones in some cases, the occurrence of cough and short-term phenomena of bronchospasm is observed, very rarely pronounced bronchospasm develops. Similar reactions are associated with irritation of the mucous membrane of the upper respiratory organs by medicinal substances.
What is the clinical pharmacology of mast cell membrane stabilizers, not everyone knows.
Other uses
Using these drugs in the form of nasal drops containing cromones, patients in some cases report the appearance of symptoms of coughing, headache, taste disturbance and irritation of the mucous membranes of the nasopharynx.
After instillation (instillation into the eyes) of these medications, sometimes there is a burning sensation, sensation in the eyes of a foreign body, swelling and hyperemia of the conjunctiva (redness).
Negative manifestations
Side effects from the use of "Ketotifen" are equal to H1-histamine blockers of the first generation. This may cause drowsiness, dry mouth, inhibition of the rate of reactions and others.
Cromoglycate sodium
This medication also has some analogues, which include:
- Cromoglycic acid;
- Ifiral;
- Kromoglin;
- "Intal";
- Cromohexal.
These membrane stabilizers prevent, but do not cure, immediate allergic reactions.
When entering the body by inhalation from the lumen of the respiratory tract of the lungsonly 10% of the initial dosage is absorbed, when taken orally - even less - only 1%, when used intranasally, 8% penetrates into the blood, and when instilled into the eyes - 0.04% of the drug.
The maximum concentration of the main substances of the substance in the blood is observed after 15-20 minutes. The effect when instilled into the eyes occurs after 2-14 days, when inhaled - after 2-4 weeks, when taken orally - after 2-5 weeks.
Indications for the appointment of this drug or its analogues are bronchial asthma (as one of the main therapy), allergic diseases of the digestive system, food allergies, ulcerative colitis (as an element of combined treatment), hay fever, allergic rhinitis and conjunctivitis.
For inhalations from this group of medicines are used:
- "Intal";
- Cromohexal;
- Ifiral.
For intranasal use:
- Ifiral;
- KromoHexal;
- Kromoglin;
- Kromosol.
As an eye drop:
- Ifiral;
- KromoHexal;
- Kromoglin;
- Stadaglycine;
- High Krom.
What else is on the list of mast cell membrane stabilizers?
Nedocromil sodium
This drug, as a mast cell membrane stimulator, is close in effect to sodium cromoglycate. It acts as a bronchodilator andanti-inflammatory effect and is used by inhalation to prevent and treat pathologies such as bronchial asthma. In this case, it is used 4-8 times a day, 4 mg for 2 breaths. The maintenance dosage is equal to the therapeutic one, however, the frequency of inhalations is 2 times a day. By the end of the first week of treatment, the therapeutic effect can already be observed.
Side effects may occur - cephalgia, cough, dyspepsia, bronchospasm. Mutually enhances the effects of β-agonists, glucocorticoids, ipratropium and theophylline bromide.
Lodoxamide
This pharmacological drug inhibits the release of histamines and other substances that contribute to allergic reactions. It is available as eye drops. Absorbed in a small amount, the half-life takes about 8 hours. This remedy is used for allergic conjunctivitis and keratitis.
It is recommended to instill one or two drops in each eye with an interval of 6 hours. Duration of treatment - up to 1 month.
In the course of therapy with this medicine, adverse symptoms may develop from the organs of vision (irritation of the conjunctiva, blurred vision, ulceration of the cornea), organs of smell (dryness of the nasal mucosa), as well as general phenomena (dizziness, nausea, and others).
During therapy, contact lenses are contraindicated.
The most popular mast cell membrane stabilizer in pharmacology is Ketotifen.
Ketotifen
This medication, as well as its analogues ("Ayrifen", "Zaditen", "Stafen") has a membrane-stabilizing effect, which is combined with H1-histamine blocking. When administered orally, it is well absorbed - the bioavailability of the drug is 55%. The maximum concentration in is achieved 3-4 hours after ingestion, the half-life is 21 hours.
What is it used for?
This medication and its analogues are used for prophylactic purposes in the event of asthma attacks, allergic rhinitis and dermatoses. It is recommended to take 1-2 mg (in the form of capsules and tablets) or 1-2 tsp. syrup 0.02% twice a day with food.
Against the background of treatment with such drugs, side symptoms may develop, for example, dry mouth, increased appetite and associated weight gain, excessive drowsiness, inhibition of the reaction rate. The drug enhances the effect of sleeping pills and sedative pharmacological agents, as well as alcohol.
Pregnancy and membrane stabilizers
The use of systemic membrane stabilizers during pregnancy is contraindicated. Topical substances - cromones - are contraindicated for use only in the first trimester and are used with caution in subsequent periods. If there are indications, for example, with allergic rhinitis and conjunctivitis of the same nature in a chronic form, after 15 weeks of pregnancy, it is allowed to use a solution of cromohexal 2% in the form of eye drops or nasal spray - instandard dosages.
During the lactation process, the use of cromones is carried out only if there are strict indications.
We reviewed the mechanism of action of mast cell membrane stabilizers.
