Which drug is commonly used for prophylaxis of rheumatic fever after streptococcal throat infections?

Penicillin is the drug of choice for prophylaxis of rheumatic fever after streptococcal throat infections due to its effectiveness in eradicating Group A Streptococcus. Rheumatic fever is a serious post-infectious complication that can occur following an untreated or inadequately treated streptococcal pharyngitis, leading to complications such as rheumatic heart disease.

Long-term antibiotic prophylaxis, particularly with penicillin, is recommended to prevent recurrence in individuals who have previously had rheumatic fever or to prevent the onset of rheumatic fever in those at high risk following strep throat. Penicillin is specifically chosen for its reliability, minimal side effect profile, and established efficacy in preventing the infection from progressing to rheumatic fever.

In contrast, while azithromycin and cephalexin can treat streptococcal infections, they are typically second-line alternatives and not the first choice for prophylaxis. Doxycycline, although it has antibacterial properties, is not effective against the organism responsible for rheumatic fever prophylaxis and does not typically show the same efficacy as penicillin in this context. Thus, penicillin remains the standard agent recommended for this prophylactic treatment.