Hazards of antihistamine dependence in psychiatric patients: a case report.

Excessive use of over-the-counter (OTC) medications has been a growing public health problem. We present the case of a patient with avoidant personality disorder, social phobia, and dull normal intelligence, with dependence to pheniramine maleate. His anxiety symptoms, initially unresponsive to conventional treatment, reduced only after stopping pheniramine during inpatient care. This case emphasizes the need for awareness and regular monitoring of the use of OTC medications in vulnerable patient populations.