<p>Clostridium difficile associated diarrhea has been reported with use of Polymyxin B. Nephrotixic reactions: Albuminuria, cylinduria, azotemia, and rising blood levels, Neurotoxic reactions: Facial flushing, dizziness progressing to ataxia, drowsiness, peripheral aresthesias (circumoral and stocking glove), apnea due to concurrent use of curariform muscle relaxants, other neurotoxic drugs or inadvertent overdosage, and signs of meningeal irritation with intrathecal administration, e.g., fever, headache, stiff neck. Other reactions occasionally reported: Drug fever, urticaria rash, severe pain at IM injections sites and thrombophelbitis at IV injections sites.</p>