Widely used as an antibiotic, it is effective against a broad range of bacteria. It is commonly applied in treating bacterial infections such as typhoid fever, meningitis, and rickettsial diseases. Due to its ability to penetrate tissues effectively, it is also used in eye infections, including conjunctivitis and trachoma, often in the form of ointments or drops. In veterinary medicine, it treats infections in livestock and pets. However, because of the risk of serious side effects like bone marrow suppression, its use in humans is often reserved for cases where other antibiotics are not suitable or effective.