National gonorrhea therapy monitoring study: treatment results

To monitor the efficacy of the 1972 United States Public Health Service recommended treatment regimens for uncomplicated gonorrhea, we studied 9008 patients who were randomly assigned either to aqueous procaine penicillin G, 4.8 million units intramuscularly plus 1 g of oral probenecid, or to one of the three other recommended regimens. Among the 3871 patients re-examined within three to seven days after therapy, the penicillin-probenecid regimen was successful in 96.8 per cent, whereas the cure rates of the ampicillin-probenecid, tetracycline, and spectinomycin regimens were 92.8, 96.2, and 94.8 per cent, respectively. In clinics comparing the regimens, penicillin G-probenecid was as effective as tetracycline, but more effective than ampicillin-probenecid (P less than 0.05) and spectinomycin (P less than 0.01). However, in patients re-examined three to 14 days after treatment, only the ampicillin-probenecid regimen was significantly less effective than penicillin probenecid (P less than 0.01). Despite these differences in results, all four regimens recommended by the Public Health Service provided effective therapy for uncomplicated gonorrhea.