Nausea, vomiting, abdominal discomfort, diarrhea, lack of appetite, abdominal pain, abdominal distension and other symptoms, insomnia, dizziness, headache and other neurological symptoms, and skin rashes, itching and other symptoms may occur during the use of levofloxacin hydrochloride. Transient liver function abnormalities, such as increased serum aminotransferase and elevated serum total bilirubin, may also occur. The incidence of these adverse reactions ranges from 0.1% to 5%. Occasionally, the rise of blood urea nitrogen, tiredness, fever, palpitation, abnormal taste, etc., generally can be tolerated, and disappear rapidly after the end of the course of treatment.　ContraindicationsAllergy to quinolones, pregnant and lactating women, patients under 18 years of age are prohibited.

Levofloxacin is contraindicated in patients with hypersensitivity to this product and to fluoroquinolones.　See norfloxacin, because the product is mainly excreted from the kidneys, people with reduced renal function need to reduce the amount of application, the elderly patients also need to reduce the amount of discretion. It is contraindicated in patients with a history of hypersensitivity to quinolone antimicrobials.　Norfloxacin and other fluoroquinolones mechanism of action for the inhibition of DNA synthesis, in young rats found that the damage to cartilage, so this kind of drugs should not be used for pediatrics, pregnant women, breastfeeding women need to be applied to suspend breastfeeding, because the drug can be secreted into the breast milk.　Patients with pre-existing central nervous system disorders such as epilepsy should avoid the application of fluoroquinolones such as this product, as it is prone to serious central nervous system reactions.　Severe renal hypoplasia should also be avoided, because of the occurrence of convulsions and other adverse reactions.　In the elderly, this agent is mainly excreted from the kidneys (see "In vivo pharmacokinetics"), however, due to the low renal function of most elderly persons, persistently high blood concentrations may occur. Therefore, attention should be paid to the dosage and dosage intervals, and caution should be exercised by administering 100mg once a day, twice a day.

Large side effects of the latter