Molecule

Drug Groups

approved

Description

A histamine H1 receptor antagonist that is effective in the treatment of chronic urticaria, dermatitis, and histamine-mediated pruritus. Unlike its major metabolite cetirizine, it does cause drowsiness. It is also effective as an antiemetic, for relief of anxiety and tension, and as a sedative. [PubChem]

Indication

For symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states in which anxiety is manifested. Useful in the management of pruritus due to allergic conditions such as chronic urticaria.

Pharmacology

Hydroxyzine, a piperazine antihistamine structurally related to buclizine, cyclizine, and meclizine, is used to treat histamine-mediated pruritus or pruritus due to allergy, nausea and vomiting, and, in combination with an opiate agonist, anxiolytic pain. Hydroxyzine is also used as a perioperative sedative and anxiolytic and to manage acute alcohol withdrawal. Hydroxyzine's active metabolite, cetirizine, is also used as an H₁-antagonist.

Toxicity

Oral, rat LD₅₀: 950 mg/kg. Symptoms of overexposure include hypersedation.

Affected Organisms

Biotransformation

Hepatic

Absorption

Rapidly absorbed from the gastrointestinal tract

Half Life

20 to 25 hours

Protein Binding

93%

References

External Links