Failure of Penicillin G Benzathine in the Treatment of Neurosyphilis

Although penicillin remains highly effective in syphilis, important questions exist regarding the optimal regimen for syphilitic involvement of the nervous system. Progression of neurosyphilis despite 7.2 million units of penicillin G benzathine occurred in the case reported here, with subsequent resolution following high-dose intravenous aqueous penicillin therapy. This and other recent reports support the conclusion that neurosyphilis should be treated with higher amounts of penicillin than is provided by the benzathine regimens.