When administered as an injection, the dosage and duration of treatment with hydroxyzine hydrochloride depend on the patient’s age, weight, and response to the medication. The usual dosage for adults is 25-100 mg, administered every 4-6 hours as needed.
As with any medication, hydroxyzine hydrochloride may cause side effects in some people. Common side effects may include drowsiness, dry mouth, and blurred vision. Less common side effects may include confusion, dizziness, and headache.