Study aim: This study will be performed to compare the pharmacokinetics and invivo parameters of two different formulation of Silymarin 210 mg. Design: Non-blinded, randomized, crossover in vivo bioequivalence study in 24 healthy males under fasting conditions. Block randomization for a treatment sequence of Test/Reference or Reference/Test is used Settings and conduct: In each period, volunteers will receive a single dose of the treatment in the Noor Research and Development Institute (Tarasht, Tehran). 2 dosing periods will be separated by a 14-day washout period. Participants/Inclusion and exclusion criteria: Inclusion Criteria: Healthy subjects (male) between 18– 55 years of age and Body Mass Index (BMI) within 15% of normal range according to the accepted normal values between 18.5 and 30 (inclusive), calculated as kg/m2. Subjects with no significant diseases or clinically significant abnormal findings during screening, medical history, clinical examination and laboratory evaluations. Exclusion Criteria: Subjects with known allergy to the products tested. Smoking more than 10 cigarettes per day and could not tolerate cigarette cessation during each clinical period. Intervention groups: Intervention group 1: Silymarin 210mg Softgel, produced by Gol Darou Pharmaceutical Co. In each period, 12 of 24 subjects will be given a single oral dose of this product. Intervention group 2: Silymarin 210mg Hard capsule, produced by Gol Darou Pharmaceutical Co. In each period, 12 of 24 subjects will be given a single oral dose of this product. Main outcome variables: Peak Plasma Concentration