Given the common need to treat conditions such as Clostridium difficile colitis, refractory bacterial vaginosis/trichomoniasis, and bacteremia/sepsis with prolonged courses of metronidazole, the astute clinician should be mindful of metronidazole-induced neuropathy as the possible etiology of numbness, tingling, and parasthesias in patients taking this medication.
This is a rare, but serious side effect which is dose and duration dependent; doses of 1000 mg to 2400 mg for at least 30 days duration is typically required to cause neuropathy.
The lower extremities are most commonly affected.
In suspected cases, use of metronidazole should immediately be stopped; sometimes symptoms never completely resolve even after cessation of use, particularly in cases of prolonged oral therapy.
