Intravenous methimazole in the treatment of refractory hyperthyroidism.

Background: Management of a hyperthyroid patient unable to take oral or rectal medication is a difficult clinical problem. The need for an alternative parenteral route of antithyroid medication administration in thyrotoxic patients occurs in certain rare cases, such as emergent gastrointestinal surgery, bowel ileus or obstruction, or severe vomiting and diarrhea. We report a simple and successful protocol for the preparation and use of intravenous methimazole (MMI) for treatment of hyperthyroidism in patients intolerant of orally and rectally administered thionamides.