Oral antimicrobials count as DDD values. The DDD value of an antimicrobial drug, also known as the limited daily dose, refers to the maintenance dose of a drug that acts in adults for its primary indication. It can be a better response to the frequency of drug use. Nowadays, many hospitals have incorporated the DDD value of antimicrobial drugs into the assessment standards of each department, which requires doctors to follow the principles of antimicrobial drug use and not to use antimicrobial drugs indiscriminately, such as using drugs without indication, not combining drugs arbitrarily, and overuse of antimicrobial drugs. The DDD value of antimicrobial drugs has nothing to do with whether they are taken orally or intravenously, but is related to the dosage of drugs used in outpatient clinics, inpatient hospitals, discharged from hospitals, and skin tests. The DDD value of antimicrobial drugs is formulated for everyone to supervise the rational use of antibiotics by doctors, which requires the cooperation of multiple departments in hospitals.