WE WISH to report a case of intoxication from a single massive dose of polymyxin B sulfate with apparently a satisfactory response to tripelennamine (Pyribenzamine). Polymyxin B sulfate is a bactericidal antibiotic derived from Bacillus polymyxa and composed of polypeptides and a fatty acid. Its use has been limited because of three types of toxic effects: neural, cutaneous, and renal.1 Neurotoxic side-reactions include paresthesias, dizziness, ataxia, and dysarthria. Renal toxicity seldom appears unless the dose is over 2.5 mg. per kilogram per day.2 Then albuminuria is common, and oliguria and nitrogen retention have been reported. Cutaneous reactions (urticarial and maculopapular rashes) respond to antihistamines.3 Neurotoxic effects disappear within 24 to 48 hours, and signs of renal toxicity usually are gone four days after the drug is discontinued.
Although the toxic effect of a large overdose of polymyxin in animals has been studied,5 there are no reports