ABSTRACT
Trihexphenidyl [Parkinol] is one of anticholinergics which is an important member of hallucinogens. It may be abused for its euphoriant and hallucinogenic effects, and it may be combined with street drugs for enhanced effect. To investigate the effect of trihexphenidyl [parkinol] dependence on biochemical parameter [liver functions tests] and histopathological examination of the liver and brain of albino rat. Twenty adult male albino rats of an average weight [150-200 grams] were divided into two equal groups as follow: Group I: [Control group]: Formed of 10 rats. Group II: [Dependent group]: Consisted of 10 rats that was given trihexphenidyl orally in gradually increasing doses until they reached the dependent dose in one month. Blood samples were collected. Biochemical parameter [liver functions tests] was done on the sera of the rats. Liver and brain tissues were taken for histological examination. Biochemical study, it was found that serum liver function tests, ALT and AST showed highly significant increased, P was <0.001, while serum albumin was significantly decreased P was<0.05 in dependent group than in control group. Histopathological examination of the liver, it showed small foci of hepatic cell necrosis with moderate periportal mononuclear cell infiltration, with subcapsular fatty degeneration and chronic venous congestion. On the other hand the brain of trihexphenidyl dependent group showed congestion, edema and degenerative changes in some neurons. From the present results, it can be concluded that trihexphenidyl [parkinol] abuse can lead to hepatotoxicity, as it affects liver function tests and the histological picture of the liver. Also trihexphenidyl abuse causes histopathological changes in the brain. So health educational programs should be held to pay attention about trihexphenidyl dependence and its deleterious effects on health and the relation between trihexphenidyl and other types of drug dependence. Neurologists and psychiatrists should be aware about the potential trihexphenidyl [parkinol] toxicity over the long term medical use by the patients, and its capability of being addicted. Also media and press should explain the deleterious effects of trihexphenidyl use for prolonged time