Trihexyphenidyl (Artane) abuse in schizophrenic patients

Area of Science:

• Psychiatry
• Clinical Psychology
• Pharmacology

Background:

• Anticholinergic medications, including Trihexyphenidyl (THP), are frequently used by patients with schizophrenia.
• The abuse potential of THP and other anticholinergics in this population is recognized, yet data on incidence and characteristics are limited.
• Understanding THP abuse patterns is crucial for managing schizophrenia treatment and preventing substance misuse.

Purpose of the Study:

• To determine the incidence of Trihexyphenidyl (THP) abuse among hospitalized schizophrenic patients.
• To compare the demographic and clinical characteristics of THP abusers with non-abusers.
• To investigate potential reasons for THP abuse, such as symptom relief or stimulant effects.

Main Methods:

• A prospective evaluation of 214 consecutive schizophrenic admissions.
• Identification of 14 patients abusing Trihexyphenidyl (THP).
• Comparison of THP abusers with a randomized control group (n=28) using demographic data, comorbidity assessments, and the Brief Psychiatric Rating Scale (BPRS).

Main Results:

• The incidence of THP abuse was found to be 6.5% (14 out of 214 patients).
• No significant differences were observed in demographic variables or comorbidity with antisocial personality disorder or other substance abuse between groups.
• THP abusers exhibited a trend towards more negative symptoms on admission and significantly higher BPRS scores, particularly for hostile-suspiciousness, at discharge.

Conclusions:

• Trihexyphenidyl (THP) abuse is a notable issue in schizophrenia treatment, occurring in 6.5% of admissions.
• Abuse may be linked to attempts to alleviate negative symptoms or drug-induced Parkinsonism, or for non-specific stimulant effects exacerbating positive symptoms.
• Clinical monitoring for THP abuse and its potential impact on symptom presentation is essential in schizophrenia care.