Sulfamethoxazole for Strep Throat: Effectiveness & Resistance

Sulfamethoxazole or sulfameth-trimethoprim (Bactrim, Septra, others) are effective against *Streptococcus pyogenes*, the bacterium that causes strep throat, and are sometimes used to treat strep throat.

Since many strains of *S. pyogenes* are resistant to this antibiotic, testing for resistance is recommended when this agent is prescribed for group A streptococcal infections.

Penicillin is the drug of choice for treating strep throat.