Biocilin 100mg Injection is an antibiotic medicine that works by killing the infection-causing bacteria in your body. It is effective for bacterial infections of the throat, ears, urinary tract, skin, soft tissues, and typhoid fever. Biocilin 100mg Injection is given by a doctor or a nurse and should not be self-administered. This medicine usually makes you feel better within a few days, but you should continue taking it as prescribed even when you feel better. Stopping it early may make the infection come back and harder to treat.