Treatment of allergic rhinitis

Pharmacotherapy of allergic rhinitis has its own characteristics:

• the effect of medications for the treatment of allergic rhinitis quickly passes after their withdrawal, therefore, in the case of a persistent form, treatment should be long-term;
• tachyphylaxis (rapidly developing tolerance) does not occur with long-term use of drugs. The exceptions are vasoconstrictors and first-generation histamine H1-receptor blockers, the use of which may cause tolerance (reduced sensitivity to the drug used);
• Medicines are usually prescribed orally or intranasally;
• Active use of glucocorticoids is usually not recommended due to the risk of developing severe side effects.

If conjunctivitis is present, the above regimen should include an H1-histamine receptor blocker or cromones in the form of eye drops.

Non-drug treatment of allergic rhinitis

Treatment of allergic rhinitis includes allergen-specific immunotherapy and pharmacotherapy.

Allergen-specific immunotherapy is a treatment with increasing doses of an allergen, which is most often administered subcutaneously (less often intranasally or sublingually). Data on the effectiveness and safety of subcutaneous immunotherapy are contradictory. It is believed that immunotherapy is most effective in children and adolescents with monovalent sensitization and a mild course of the disease.

It must be carried out strictly according to indications.

Indications for subcutaneous specific immunotherapy:

• insufficient effectiveness of drug therapy;
• patient's refusal of drug treatment;
• manifestation of adverse effects of drugs;
• period of stable clinical and functional remission:
• accurate identification of the allergen.

Subcutaneous immunotherapy should be performed by an allergist in a specialized allergology office.

Alternative treatments such as homeopathy, acupuncture, and phytotherapy are often used. However, there is currently no scientific evidence to support the effectiveness of these methods.

Drug treatment of allergic rhinitis

The tactics of drug treatment depend on the severity of the disease and include certain groups of drugs.

Antihistamines are used to treat allergic rhinitis.

• First generation drugs: chloropyramine, clemastine, mebhydrolin, promethazine, diphenhydramine,
• Second generation drugs: acrivastine, cetirizine, loratadine, ebastine,
• Third-generation drugs: desloratadine, fexofenadine. First-generation antihistamines (competitive histamine H1-receptor antagonists) have a number of disadvantages. The main undesirable properties of this group of drugs are considered to be short-term action, pronounced sedative effect, development of tachyphylaxis, which requires frequent replacement of one drug for another (every 7-10 days). In addition, these drugs have atropine-like effects (dry mucous membranes, urinary retention, exacerbation of glaucoma).

Second-generation antihistamines are highly selective histamine H1 receptor blockers. These drugs do not have a sedative effect, or it is insignificant, do not have an anticholinergic effect, there is no tachyphylaxis when taking them, the drugs have a long-term effect (they can be taken once a day). Modern histamine H1 receptor blockers are effective in relieving many symptoms, such as rhinorrhea, sneezing, itching in the nose and nasopharynx, eye symptoms. Compared with first-generation antihistamines, second-generation antihistamines are more effective and safe. In this group of drugs, ebastine is considered one of the most effective and fast-acting. In addition, it has a 24-hour effect, which allows it to be used not only as an "emergency remedy", but also as a drug for the planned therapy of allergic rhinitis.

Third-generation antihistamines are highly selective blockers of H2-histamine receptors. New, but already well-proven desloratadine is an active metabolite of loratadine. Desloratadine is currently the most powerful of the existing antihistamines. In therapeutic doses, it has antihistamine, antiallergic and anti-inflammatory effects. In terms of blocking the main mediators of allergic inflammation, the effectiveness of desloratadine is comparable to dexamethasone. The effect of the drug appears within 30 minutes after administration and lasts for 24 hours. A significant decrease in nasal congestion in allergic rhinitis has been noted against the background of desloratadine intake.

Fexofenadine is a fast-acting and effective antihistamine. It is rapidly absorbed, the concentration in blood plasma is maximum 1-5 hours after oral administration, the effect after a single dose lasts for 24 hours. In therapeutic doses (up to 360 mg), fexofenadine does not have an undesirable effect on psychomotor and cognitive functions.

Local antihistamines: azelastine, dimethindene-phenylephrine are available as nasal spray and eye drops. These drugs are recommended for mild forms of the disease (nasal forms stop rhinorrhea and sneezing) and to eliminate the symptoms of allergic conjunctivitis. The advantages of these drugs: rapid onset of effect (in 10-15 minutes) and good tolerability. Azelastine and levocabastine are used 2 times a day after nasal cavity toilet.

Glucocorticoids used to treat allergic rhinitis: beclomethasone, mometasone, fluticasone, hydrocortisone, prednisolone, methylprednisolone. Local glucocorticoids are the most effective means of daily treatment of all forms of allergic rhinitis. Their high efficiency is due to the pronounced anti-inflammatory effect and influence on all stages of development of allergic rhinitis. They reduce the number of mast cells and secretion of mediators of allergic inflammation, reduce the number of eosinophils, T-lymphocytes, inhibit the synthesis of prostaglandins and leukotrienes, suppress the expression of adhesion molecules. All these effects lead to a decrease in tissue edema and normalization of nasal breathing, a decrease in the secretion of mucous glands, a decrease in the sensitivity of receptors of the nasal mucosa to irritants. This, in turn, causes the cessation of rhinorrhea and sneezing, suppression of specific and non-specific nasal hyperreactivity. Patients tolerate modern glucocorticoid drugs well. When using them, atrophy of the nasal mucosa and inhibition of mucociliary transport do not occur. The bioavailability of drugs in this group is very low, which ensures their systemic safety. Rare side effects in the form of dry nose, crusting or short-term nosebleeds are reversible and are usually associated with an overdose of the drug. Glucocorticoids are effective not only against allergic rhinitis, but also against concomitant allergic diseases, primarily bronchial asthma.

The first representative of the group of local intranasal glucocorticosteroids beclomethasone, which has been used to treat allergic rhinitis and bronchial asthma since 1974. Beclomethasone is considered the "gold standard" of basic therapy for allergic rhinitis. Intranasal forms of beclomethasone reduce the severity of the asthmatic component. Nasobek is a metered spray containing an aqueous suspension of beclomethasone, has a convenient mode of application: 2 times a day. The drug affects the receptors of the nasal mucosa, does not dry or irritate it, which allows you to quickly and effectively eliminate the main symptoms. At the same time, the incidence of side effects is low. Aldecin (a beclomethasone drug) has been widely used in clinical practice by otolaryngologists and allergists for 10 years. The drug has proven itself as an effective and safe remedy for the treatment of allergic rhinitis, nasal pollinosis and bronchial asthma. The presence of two attachments (for the nose and mouth) makes the use of the drug more convenient. A small amount of active substance (50 mcg) in 1 standard dose allows for individual selection of the required daily dose for adults and children.

Mometasone begins to act within the first 12 hours after administration. The use of mometasone once a day allows to stop all symptoms of allergic rhinitis, including nasal congestion, for 24 hours, which increases patient compliance. Due to low bioavailability (less than 0.1%), the use of mometasone guarantees high systemic safety (not detected in the blood even at a 20-fold excess of the daily dose). Mometasone does not cause dryness in the nasal cavity, since it contains a humidifier. With long-term use (12 months), mometasone does not cause atrophy of the nasal mucosa, but, on the contrary, helps to restore its normal histological structure. The drug is approved for use in children from two years of age.

Fluticasone has a pronounced anti-inflammatory effect. In average therapeutic doses, it does not have systemic activity. It has been established that fluticasone significantly reduces the production of inflammatory mediators of the early and late phases of allergic rhinitis. Fluticasone nasal spray has a rapid soothing and cooling effect on the nasal mucosa: it reduces congestion, itching, runny nose, discomfort in the paranasal sinuses and a feeling of pressure around the nose and eyes. The drug is released in bottles equipped with a convenient dosing spray. The drug is used 1 time per day.

Systemic glucocorticoids (hydrocortisone, prednisolone, methylprednisolone) are used to treat severe forms of allergic rhinitis during exacerbation in a short course when other methods are ineffective. The treatment regimen is selected individually.

Mast cell membrane stabilizers: cromones (cromoglycate) and ketotifen. Mast cell membrane stabilizers are used to prevent intermittent allergic rhinitis or to eliminate intermittent symptoms of the disease, since these drugs do not have a sufficient effect on nasal obstruction. The membrane-stabilizing effect of these drugs develops slowly (within 1-2 weeks), another significant drawback is the need for 4 times a day, which creates significant inconvenience for patients. It should be noted that cromones do not have side effects. This allows them to be used in children and pregnant women.

Vasoconstrictors: naphazoline, oxymetazoline, tetryzoline, xylometazoline. Vasoconstrictors (alpha-adrenergic agonists) are used in the form of drops or sprays. They effectively and quickly restore nasal breathing for a short time. With short courses of treatment (up to 10 days), they do not cause irreversible changes in the mucous membrane of the nasal cavity. However, with longer use, a "rebound" syndrome develops: persistent edema of the mucous membrane of the nasal concha, profuse rhinorrhea, and changes in the morphological structure of the mucous membrane of the nasal cavity occur.

M-cholinergic receptor blockers: ipratropium bromide. The drug has virtually no systemic anticholinergic activity, locally blocks M-cholinergic receptors, reducing rhinorrhea. It is used to treat moderate and severe forms of persistent allergic rhinitis as part of complex therapy.

Mucolytics: acetylcysteine and carbocysteine are advisable to prescribe for protracted intermittent forms.

Considering that allergic inflammation is a chronic process, therapeutic efforts should be concentrated on the correct selection of basic therapy. Basic therapy drugs can be glucocorticoids and cromones.

Vasoconstrictors and H1-histamine receptor blockers are used as symptomatic agents in allergic rhinitis. The exception is mild forms of seasonal (intermittent) allergic rhinitis, when only these groups of drugs can be used.

Further management

Patients with allergic rhinitis need regular medical check-ups with an otolaryngologist and allergist. This is due to the risk of developing polypous rhinosinusitis and bronchial asthma in patients with allergic rhinitis. Patients should visit an otolaryngologist 1-2 times a year.