Norfloxacin is one kind of quinolone antibiotics, and the possible adverse reactions of taking Norfloxacin include gastrointestinal reaction, central nervous system reaction, skin allergy and so on. It is recommended that patients strictly follow the doctor’s instructions to use the drug, it is strictly prohibited to change the dose of the drug to prevent serious adverse reactions. 1. Gastrointestinal reaction: some patients will have nausea, vomiting, diarrhea, epigastric pain and other gastrointestinal reactions after taking norfloxacin, taking the drug before meals can effectively relieve gastrointestinal reactions. 2. Central nervous system reaction: taking quinolone antibiotics such as norfloxacin for a long time, the drug may pass through the blood-brain barrier leading to drowsiness, headache, dizziness and other central nervous system reactions. 3. Skin allergy: patients who are allergic to quinolone antibiotics may experience adverse reactions such as skin papules and itchy skin after taking norfloxacin. Norfloxacin is commonly used in the treatment of urinary tract infections, Klebsiella pneumonia and other diseases. Patients are advised to use the medication under the guidance of a doctor, and if adverse reactions occur, they need to consult a doctor promptly.