Can Cephalexin Treat a Sinus Infection?

Cephalexin may work against some bacteria, but it is generally not a first-choice treatment for acute bacterial sinusitis because it may not reliably cover common causes. Healthcare providers usually select an antibiotic based on current guidelines, allergies, and individual risk factors. If cephalexin is prescribed, the dose and treatment length should be determined by a healthcare provider based on the patient’s age, kidney function, infection, and other clinical factors. However, cephalexin is not effective against viral sinus infections, which account for 90-95% of acute sinusitis cases. Your healthcare provider will determine if your symptoms indicate a bacterial infection requiring antibiotic treatment versus supportive care for viral sinusitis.