[Methimazole and propylthiouracil induced acute toxic hepatitis].

Hyperthyroidism is one of the most common endocrinology disorders. Treatment can be either pharmacological, surgical or using radioactive iodine. In Europe methimazole is the antithyroid drug of choice because it can be administered in a single daily dose and has a lower risk of adverse reactions. Around 5% of patients taking thionamides can present any of their side effects, which are usually mild. Liver toxicity due to thionamides is very rare, and severe due to propylthiouracil. We present a clinical case of a cholestatic jaundice and acute toxic hepatitis due to methimazole and a cross-reaction with propylthiouracil. Based on this case a review is presented.