<prompt> Despite its age, penicillin G remains the drug of choice in the treatment of infections caused byB. fragilisT. pallidumH. influenzaeE. coli  <response>: Indications for the use of penicillin G are currently limited for a number of reasons. The drug has a narrow spectrum, is susceptible to beta-lactamases, and may cause hypersensitivity, and alternative antibiotics are available. However, penicillin G remains the drug of choice in syphilis, usually given IM as benzathine penicillin G, but as the Na or K salt IV in neurosyphilis. What would you do for patients who are highly allergic to penicillins? Consider tetracyclines, or possibly desensitization. 