Astemizole
- Atc Codes:R06AX11
- CAS Codes:68844-77-9
- PHARMGKB ID:68844-77-9
Table of contents
- Brand Names
- Chemistry
- Pharmacologic Category
- Mechanism of Action
- Therapeutic Use
- Pregnancy and Lactation Implications
- Contraindications
- Warnings and Precautions
- Adverse Reactions
- Genes that may be involved
- Substrate of
- Inhibits
- Drug Interactions
- Dosage
- Pharmacokinetics and Pharmacodynamics
Brand Names
Europe
Poland: Astemizol, Hismanal (d).
North America
USA: Hismanal (d).
Latin America
Mexico: Alerken, Alermi, Aleztem, Anerzol, Astesen, Aztil, Aztrolen, Biostan, Emizol, Farmidal, Fustermizol, Histalino, Histaser, Novasten, Practizol.
Drug combinations
Chemistry
Astemizole: C~28~H~31~FN~4~O. Mw: 458.58. (1) 1H-Benzimidazol-2-amine, 1-[(4-fluorophenyl)methyl]-N-[1-[2-(4-methoxyphenyl)ethyl]-4-piperidinyl]-; (2) 1-(p-Fluorobenzyl)-2-[[1-(p-methoxyphenethyl)-4-piperidyl]amino]benzimidazole. CAS-68844-77-9 (1979).
Pharmacologic Category
Antihistamine Drugs; Histamine H~1~ Receptor Antagonist. (ATC-Code: R06AX11).
Mechanism of action
Astemizole is a long-acting, selective histamine H~1~-receptor antagonist. Receptor binding studies in animals demonstrated that at pharmacological doses, it occupies peripheral H~1~-receptors but does not reach H~1~-receptors in the brain. Astemizole does not readily cross the blood-brain barrier. Anticholinergic effects have not been shown in animals. Studies in humans using the recommended dosage regimens to determine whether astemizole is associated with a different frequency of anticholinergic effects than therapeutic doses of other antihistamines have not been performed.
Therapeutic use
Relief of symptoms associated with seasonal allergic rhinitis and chronic idiopathic urticaria (should not be used for immediate relief of symptoms).
Pregnancy and lactiation implications
There are no adequate studies in pregnant women. Should be used during pregnancy only if potential benefit to the mother justifies potential risk to the fetus. Not recommended during lactation (excretion in breast milk unknown).
Unlabeled use
Contraindications
Hypersensitivity to astemizole or any of the active ingredients. Concomitant administration of astemizole with erythromycin or with ketoconazole tablets.
Warnings and precautions
Avoid astemizole in patients who are taking medications which are reported to prolong QT intervals (including probucol, certain antiarrhythmics, certain tricyclic antidepressants, certain phenothiazines, certain calcium channel blockers such as bepridil, and terfenadine), patients with electrolyte abnormalities such as hypokalemia or hypomagnesemia, or those taking diuretics with potential for inducing electrolyte abnormalities. Rare cases of cardiovascular events observed in hepatic dysfunction. Since astemizole is extensively metabolized by the liver, the use of astemizole in significant hepatic dysfunction should generally be avoided. Caution should be given regarding potential anticholinergic (drying) effects in lower airway diseases. Caution should also be used when treating patients with renal impairment (astemizole does not appear to be dialyzable).