A case of metronidazole-induced neuropathy treated by medication for neuropathic pain

Abstract

Metronidazole (MNZ) is an antibiotic effective for anaerobic bacteria and protozoa. Drug-induced neuropathy is sometimes caused by various drugs, including MNZ. We report a case of MNZ-induced peripheral neuropathy that was alleviated by medication for neuropathic pain. Five months ago, a 77-year-old male had lumbago and was diagnosed as having disseminated nontuberculous spondylitis. One month after administration of MNZ, 1,500 mg/day, he developed pain and numbness in both hands and feet, diplopia, and dysarthria, and thus drug-induced neuropathy was suspected. Several days after discontinuation of MNZ, central neuropathy symptoms were improved, but peripheral neuropathy symptoms remained. He was referred to our clinic because pregabalin 75 mg/day and tramadol/acetaminophen combination 2 tablets/day, were not effective. We increased the dose of pregabalin to 150 mg/day, which improved his pain, but not his numbness. It seems quite likely that pregabalin is effective for pain of drug-induced peripheral neuropathy, but not for numbness.