Problem in the use of antibiotics in present is antibiotic-resistant or drug resistant. We had antibiotic-resistant because when we had infection of bacteria not allowed doctor's order properly such as stopping take medicine halfway. Normally, we need to take antibiotics a whole course. Although we feel recovered still should have to take it out. When we don't take the medicine according to the doctor so bacteria will develop antibacterial resistance which caused antibiotic-resistance. But now, bacteria can develop to difficult to treat so it is therefore necessary to discover new classes of antibiotics for always.