Single dose, "block-replace" drug therapy in hyperthyroidism.

In 30 consecutive hyperthyroid patients with diffuse goitre divided dose therapy with carbimazole 40 mg and triiodothyronine 80 mug daily was shown to produce total or subtotal block in thyroid hormonogenesis. Once produced, this block could be invariably maintained with an equivalent single daily dose for periods up to three years. Its notable acceptability to patients, a more stable degree of euthyroid control, ease of assessing suppressibility of trapping, and ability to treat patients in remote areas all support a wider use of this mode of therapy.