Reversal of phrenic nerve palsy with topiramate.

A 57-year-old Caucasian man presented with diaphragmatic paralysis and type 2 diabetes. He had severe orthopnea that remained unchanged for 1 year. He was later diagnosed with distal symmetric polyneuropathy and was started on topiramate. Within 26 weeks of treatment, the patient showed improvement in diaphragmatic function and regrowth of intraepidermal nerve fibers, accompanied by improvement in respiratory and peripheral neuropathy symptoms. Topiramate may prove to be an effective agent in the treatment of nonremitting diaphragmatic paralysis and regrowth of intraepidermal nerve fibers.