Benzathine penicillin is a long-acting form of penicillin, an antibiotic used to treat various bacterial infections. It is commonly administered through an injection and works by stopping the growth of bacteria. This medication is particularly effective against infections like rheumatic fever and syphilis. Due to its extended release, benzathine penicillin remains active in the body for several weeks, allowing for less frequent dosing compared to other antibiotics. It is important for patients to follow their healthcare provider's instructions when receiving this treatment to ensure its effectiveness and minimize potential side effects.