Doxycycline tablets belong to the tetracycline class of antibiotics, mainly used for rickettsial, mycoplasma and chlamydia infections, and have corresponding efficacy for regression fever, plague, cholera and rabbit fever. Cross-resistance exists between doxycycline and different varieties of tetracycline antibiotics, so pay attention to the course of treatment during taking the drug, if the drug is taken for a long time, it may cause secondary infection or liver and kidney function damage, once it happens, stop the drug immediately and seek medical treatment. This product can be taken with food, milk or carbonate drinks. Gastrointestinal adverse reactions such as nausea, vomiting, abdominal pain and diarrhea may occur during the administration of the drug. Therefore, it should be noted that this adverse reaction occurs mostly in patients who are bedridden immediately after taking the drug; patients are advised not to be directly exposed to sunlight or ultraviolet light while taking the drug, as skin erythema reaction is likely to occur, and if this symptom occurs, the drug should be discontinued immediately and medical attention should be sought. This product and barbiturate, phenytoin sodium, carbamazepine and other drugs at the same time will appear drug interaction, so pay attention to avoid the combination with such drugs, and for the dosage adjustment during the medication should consult a doctor or pharmacist, and finally, please note that the specific use of drugs please combine with clinical, subject to the guidance of the doctor’s interview.