Hypokalemic myopathy in pseudohyperaldosteronism induced by fluoroprednisolone-containing nasal spray.

A man who was using 9-alpha-fluoroprednisolone-containing nasal spray preparation for allergic rhinitis developed a pseudohyperaldosteronism and an acute hypokalemic myopathy. Muscle biopsy changes included variation in fiber size with preserved type 2a fibers, necrosis, phagocytosis and regeneration. This factitious mineralocorticoid excess syndrome, induced by uncontrolled use of intranasally administered steroid, should be considered among the various causes of hypokalemic myopathy.