Hydroxyzine HCl interacts with other antihistamines and medications that cause drowsiness or sedation, according to WebMD. These medications include muscle relaxants, narcotic pain relievers and benzodiazapines or barbituates. Non-prescription cough and cold products causing drowsiness should also be avoided while taking hydroxyzine.
Hydroxyzine hydrochloride is an antihistamine used to treat allergic reactions, explains RxList. It also decreases activity in the central nervous system, making it a useful sedative before or after receiving general anaesthesia and as a short-term treatment for anxiety. It may also be used to treat nausea and vomiting.
Drowsiness and dizziness, dry mouth, blurred vision and headache are among the most common side effects of hydroxyzine, notes Drugs.com. More serious side effects include confusion and seizures, tremors and repetitive movements of the tongue, lips, jaw or neck. A physician should be contacted immediately should these occur. Hydroxyzine may cause allergic reactions requiring immediate medical care. If swelling of the face, lips, tongue or throat occurs, or the person has difficulty breathing, she should get medical care at once.
Hydroxyzine should be used with caution by people with a history of respiratory problems, glaucoma, cardiovascular disease and kidney or liver disease, states WebMD. People with seizure disorders, stomach and intestinal problems, difficulty with urination and overactive thyroid should also use hydroxyzine with care.