Myxedema coma leading to respiratory depression in a dog.

A 10-year-old, intact male, cocker spaniel was presented with hypothermia, without shivering, and progressive stupor leading to coma. Myxedema coma, potentially precipitated by diuretic therapy, was tentatively diagnosed and treatment initiated, but progressive respiratory depression led to the decision to euthanize. Postmortem findings supported the diagnosis of myxedema coma.