Description Dimetindene (Fenistil) is an antihistamine/anticholinergic used orally and locally as an antipruritic. Indication Indicated as symptomatic treatment of allergic reactions: urticaria, allergies of the upper respiratory tract such as hey fever and perennial rhinitis, food and drug allergies- pruritus of various origins, except pruritus due to cholestasis- insect bites. Dimethindene is also indicated for pruritus in eruptive skin diseases such as chicken-pox. Dimethindene can also be used as an adjuvant in eczema and other pruriginous dermatoses of allergic origin. Mechanism of action Dimethindene is a selective histamine H1 antagonist and binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine.