Trihexyphenidyl (Artane) dependence: A controlled investigation between users and abusers

This controlled study aims to identify the socioclinical factors predisposing psychiatric patients to abuse trihexyphenidyl (artane) and to document the extrapyramidal symptoms in artane abusers and users. Thirty patients (n=30), with mainly two major functional psychoses and who were abusing trihexyphenidyl, were compared with 90 artane user patients (n=90), who were matched for both the diagnosis and treatment. Besides a detailed clinical interview, each patient was assessed by using DSM-IIIR criteria, Brief Psychiatric Rating Scale, Simpson and Angus Scale, and Abnormal Involuntary Movement Scale. The analysis of data showed that, compared with users, trihexyphenidyl abusers were significantly characterized by being unmarried, unemployed, smokers and having past and concurrent history of multiple drug abuse, and genetic loading of mental disorders. Both groups of patients were prescribed antipsychotic drugs and trihexyphenidyl on a longer basis. Besides other socioclinical parameters, premorbid personalities, stressful life events and extrapyramidals, including tardive dyskinesias, we did not differentiate between the two groups. Artane abusers, when compared with users, were significantly characterized by less negative psychopathology. However, other psychopathological domains, in particular, the positive symptoms and depression, did not differentiate between abusers and users. In conclusion, patients having these socioclinical profiles tend to develop trihexyphenidyl abuse. The mental health professionals should not prescribe trihexyphenidyl indiscriminately or for a long time to such patients, who indeed require long-term antipsychotic maintenance medications.