Dimetindate

Dimetindate refers to salt forms of the antihistamine dimetindene, most commonly encountered as dimetindene salts such as the dimetindene maleate. In pharmaceutical use, these dimetindene salts are employed for their antihistaminic properties and as components of formulations intended to relieve allergic symptoms.

Medical use and indications

Dimetindate-containing preparations are used to treat symptoms of allergic reactions and conditions such as hay fever, urticaria, contact dermatitis, and pruritus. They may be formulated for oral, topical, or sometimes injectable use, depending on the product and regional practice. The aim is to reduce itch, sneezing, rhinorrhea, and other histamine-driven symptoms.

Mechanism of action

Dimetindene, and by extension its salts, act as antagonists of histamine H1 receptors. By blocking the action of endogenous histamine, dimetindate reduces vascular permeability, itch, and other inflammatory effects associated with allergic reactions. As a first-generation antihistamine, dimetindate can cross the blood-brain barrier, contributing to sedative effects in some users.

Pharmacology and forms

Dimetindate is typically supplied as dimetindene salts in tablets, capsules, liquid suspensions, or topical preparations. Absorption after oral administration is relatively rapid, and the compound is metabolized in the liver with metabolites excreted mainly in the urine. The specific pharmacokinetic profile can vary by salt form and route of administration.

Safety and regulation

Common adverse effects include drowsiness or sedation, dry mouth, blurred vision, and in some cases dizziness or fatigue. Anticholinergic effects can occur, and care should be taken when driving or operating machinery. Use in pregnancy or nursing should be based on risk-benefit assessment. Availability and regulation vary by country; many dimetindene salts are sold OTC in some regions and by prescription in others.

See also

Dimetindene; Fenistil; antihistamines; H1 receptor antagonists.