Single daily dose of methimazole compared to every 8 hours propylthiouracil in the treatment of hyperthyroidism

This study to compare single-dose and multiple-dose antithyroid therapy was prompted by a perceived lack of compliance in our University Medical Clinics by those patients using multidose regimens. Twenty-two hyperthyroid patients were randomly assigned to two therapy groups. Twelve received methimazole (Tapazole) 30 mg once daily in the morning; 10 received propylthiouracil 100 mg every 8 hours. Patients were seen every 4 weeks for 3 months and assessed clinically, as well as having the appropriate thyroid tests done. Univariate analysis revealed no difference in the two groups at baseline. Posttreatment assessment revealed the once-a-day methimazole therapy to be just as effective as propylthiouracil in improving thyroid indices and clinical markers. Compliance with methimazole was 83.3% compared to 53.3% with propylthiouracil. In conclusion, once-a-day methimazole was just as effective as propylthiouracil every 8 hours in this population. Compliance was also improved with the once-a-day therapy.