ABSTRACT
Hepatic toxicity is the most serious adverse effect of anti tuberculosis drugs. This study was performed to evaluate efficacy of silymarin as a hepatoprotective herbal agent. In a randomized double blind clinical trial 70 new cases of pulmonary tuberculosis were divided into two groups. The intervention group was assigned to receive silymarin and the control group received placebo. Tuberculosis was treated by classic regimen consisting isoniazid, rifampin, pyrazinamide and ethambutol. No statistically significant difference was found between the two groups concerning the frequency of drug induced liver injury or mild elevation of liver enzymes. Silymarin was safe without any major side effect. Our results showed no significant hepatoprotective effect of silymarin among patients on tuberculosis treatment