About Hydroxyzine A first-generation H1 antagonist,piperazine derivative, Antihistamine, Antiemetic, Anxiolytic, Sedative-hypnotic. Mechanism of Action of Hydroxyzine Hydroxyzine compete with Histamine for H1receptor.It blocks the Histamine action s on the effector`s cell surface. It has sedative, Antiemetic, antimuscarinic and spasmolytic property. Antianxiety action: Hydroxyzine produces its anxiolytic action through suppression of activity at subcortical levels. Interactions for Hydroxyzine CNS Depressants (Barbiturates, hypnotics, opiod analgesics): Potentiation of CNS depressant effect. MAOIs, TCAs, Atropine: Potentiate antimuscarinic effects. Aminoglycosides: Ototoxicity of aminoglycosides masked. Aminophyllline, Benzyl penicillin, Chloramphenicol: Incompatible with these drugs. Incompatibility reported with aminophylline, benzyl penicillin salts, chloramphenicol, sodium succinate, thioridazine and some soluble barbiturates.