Cephalexin capsules belong to the first generation of oral cephalosporins and are used for the treatment of mild to moderate infections caused by sensitive bacteria, mainly for the treatment of respiratory system infections such as acute tonsillitis, pharyngitis, otitis media, sinusitis, bronchitis and pneumonia, etc. They can also be used for the treatment of urinary system infections and skin soft tissue infections. This drug is well absorbed orally, widely distributed in the body, and is not metabolized in the body, but mainly eliminated from the body in its original form through the kidneys in urine. The main adverse reactions are allergic reactions, and gastrointestinal symptoms can also be seen, with patients showing nausea, vomiting, abdominal pain, diarrhea, etc. Rarely, central nervous system symptoms are seen, with patients experiencing dizziness, tinnitus, convulsions and other neurological symptoms, as well as elevated liver liver enzymes and reduced platelet and neutrophil counts in the blood.