A single dose of penicillin works just as well to cure early syphilis as the three-injection regimen now used by many doctors, a new clinical trial says. Second and third doses of benzathine penicillin G don't provide any additional benefit in treating early-stage syphilis, researchers reported in the New England Journal of Medicine . "Benzathine penicillin G is highly effective against syphilis, but the three-dose regimen can be burdensome and deter people from attending follow-up visits with