Widely used as an antibiotic, it treats a variety of bacterial infections including respiratory tract infections, skin infections, and ear infections. It is especially useful for patients allergic to penicillin. Commonly prescribed for sinusitis, pneumonia, bronchitis, and certain sexually transmitted infections like chlamydia. Also used in pediatric medicine due to its favorable safety profile and availability in liquid form. Effective against gram-positive bacteria and some gram-negative organisms. Often chosen for its ability to penetrate tissues and achieve high concentrations in lungs and tonsils.