<p>Patients who have taken barbiturates, tricyclic antidepressants and alcohol may show diminished ability to metabolise large doses of Paracetamol. Alcohol can increase the hepatotoxicity of Paracetamol overdosage. Chronic ingestion of anticonvulsants or oral steroid contraceptives induce liver enzymes and may prevent attainment of therapeutic Paracetamol levels by increasing first-pass metabolism or clearance.</p>