Ralph Fleischman

The bactericidal action of penicillin in vivo: the participation of the host, and the slow recovery of the surviving organisms.

Excerpt Although penicillin is known to be actively bactericidal, there is reason to believe that its therapeutic activity is not determined solely by that direct bactericidal action, and that othe...

Therapeutic Activity of Bacitracin in Rabbit Syphilis, and Its Synergistic Action with Penicillin.

Summary Bacitracin has been shown to be effective in the treatment of rabbit syphilis. An intramuscular dose of 2,300 units/kg repeated once daily for 4 days, cured approximately half the animals tested. A striking synergism was noted in the therapeutic effect of penicillin and bacitracin. As little as 1 mg/kg of penicillin (approximately 1/40th of the CD50 dosage of penicillin alone) and 1,280 units/kg of bacitracin (approximately l/7th of the CD50 value) were curative if used in conjunction. These data are reported because of their possible significance in relation to the treatment of the human disease.