How often can you take atarax (hydroxyzine) to help with itching?

Every 4 -6 hours. The usual dose of Atarax is 25 mg every 6 hours. You can increase to 50mg, and take as often as every 4 hours, but the side effects of drowsiness and dry mouth are more severe at higher doses. The generic name of Atarax is hydroxyzine, which is also available as vistaril.
Atarax (hydroxyzine) As directed or every 6 hours. It can make people drowsy so consider using a non-sedating antihistamine (cetirizine) once to twice daily in the morning and afternoon and reserving the Atarax (hydroxyzine) to bedtime when itching tends to get worse.