Description
Pharmacological action
Agonist of H1-histamine receptors of vessels of the inner ear and an antagonist of H3-histamine receptors of the vestibular nuclei of the central nervous system (CNS).
Does not affect H2-histamine receptors, which improves blood circulation in the vascular strip of the inner ear due to the relaxing effect on the precapillary sphincters of the cochlea and labyrinth. Relieves symptoms in Meniere’s syndrome and vertigo.
Pharmacokinetics
When taken orally, it is rapidly and completely absorbed in the digestive tract. Communication with plasma proteins is low (less than 5%). The maximum concentration in blood plasma (Cmax) is reached after 1 h.
When taking the drug with food, the maximum concentration of the drug in the blood is lower than when taken on an empty stomach, however, the total absorption of betahistine is the same in both cases, which indicates that eating only slows down the absorption of betahistine. It is metabolized in the liver with the formation of an inactive metabolite of 2-pyridylacetic acid.
Almost completely (90, 7%) is excreted by the kidneys as a metabolite (2-pyridylacetic acid) within 24 hours. The elimination half-life is 3-4 hours. Excretion rate remains constant, indicating the linear pharmacokinetics of betahistine.
Indications
Meniere’s syndrome, characterized by the following main symptoms:
– dizziness (accompanied by nausea / vomiting)
– hearing loss
– tinnitus
Symptomatic treatment and prevention of vestibular dizziness (vertigo) of various etiologies.
Contraindications
Hypersensitivity to any of the components of the drug. Due to the lack of data on effectiveness and safety: pregnancy and lactation, the age is up to 18 years.
With caution
Betagistin should be prescribed with caution in the treatment of patients with a history of gastric ulcer and duodenal ulcer. Patients with pheochromocytoma and bronchial asthma during the treatment period should be regularly observed by a doctor.
Special instructions
Effect on the ability to drive vehicles and mechanisms
According to the results of clinical trials, the effect of betahistine on the ability to drive a car and other mechanisms is absent or insignificant, since there are no effects potentially affecting this ability.
Side effects of
From the gastrointestinal tract: often (from> 1/100 to <1/10) - nausea and dyspepsia. From the side of the nervous system: often (from> 1/100 to <1/10) - headache. In addition to these effects identified during clinical trials, the following side effects have been reported during post-marketing use and in the scientific literature (insufficient data available, to estimate their frequency): From the gastrointestinal tract: mild disorders such as vomiting, pain in the gastrointestinal tract, bloating. As a rule, these effects disappear if you take the drug simultaneously with food or after a dose reduction. From the skin and subcutaneous fat: angioedema, urticaria, pruritus, and rash. On the part of the immune system: hypersensitivity reaction, including anaphylactic reaction reported. Overdose Symptoms: After taking the drug in doses up to 640 mg, mild to moderate symptoms (nausea, drowsiness, abdominal pain) may occur. More serious complications (for example, convulsions, cardiopulmonary complications) can occur when taking high doses of betahistine, especially in combination with other drugs. Treatment: symptomatic. Patients with pheochromocytoma should use the drug under medical supervision. Storage conditions At a temperature not exceeding 25 ° C. Keep out of the reach of children! Expiration 3 years. Deystvuyuschee substances betahistine dosage formulations tablets Appointment Vzrosl m in naznacheniyu Vracha
