Hydroxyzine

Hydroxyzine is an anxiolytic which is not widely used, except for minor outbreaks of anxiety. It belongs to a class of medicines called the histamine antagonists, which are usually intended to treat allergic reactions.

How does hydroxyzine work?

Hydroxyzine is a piperazine derivative which is chemically unrelated to the phenothiazines or benzodiazepines. It is a central and peripheral histamine H1 receptor antagonist which also has anticholinergic properties.

Does it have contraindications or precautions?

Hydroxyzine can cause several side effects: drowsiness, ocular problems with raised intraocular pressure and therefore a risk of acute glaucoma. It is contraindicated in glaucoma, pregnancy and in people who arebreast-feeding.

Sources:

• Merck Manual, 4^th edition
• Pharmacorama, website accessed on 17 July 2011
• University of Strasbourg, website accessed on 5 August 2011