The cause of diarrhea on germicidal medication may be a dysbiosis of the intestinal flora caused by the administration of germicidal medication, resulting in the patient experiencing diarrhea and other symptoms. If necessary, it is necessary to consider changing the bactericidal drug, stopping the drug, adding probiotics or antidiarrheal drugs. Germicidal drugs are categorized into internal drugs such as metronidazole and amoxicillin and external drugs such as potassium permanganate. Under normal circumstances the human intestinal flora in a balanced state, some internal drugs such as amoxicillin, clarithromycin, etc. are more likely to lead to intestinal flora imbalance, diarrhea, bloating and other digestive symptoms. After diarrhea symptoms, can be replaced with levofloxacin, furazolidone and other bactericidal drugs that are not easy to cause diarrhea; if necessary, discontinue bactericidal drugs; you can take probiotics to regulate the intestinal flora; you can take antidiarrheal drugs such as montelukast, etc.; and at the same time, you need to ensure that the mood is happy, sleep enough, etc.. Sterilizing drugs eaten diarrhea should be timely to the hospital, follow the doctor’s instructions to regulate the treatment program, do not self-medication, so as not to delay the condition or adverse reactions.