Tetracycline works as a broad-spectrum antibiotic and is bacteriostatic. Side effects are mainly accompanied by gastrointestinal symptoms nausea, vomiting, epigastric discomfort and so on. 1. Role: tetracycline has an inhibitory effect on most gram-positive and negative bacteria, high concentrations of tetracycline can kill mycoplasma, chlamydia and other uncommon pathogens, to improve the infection has a greater help and can inhibit viruses and so on. 2. Side effects: tetracycline side effects are mainly associated with gastrointestinal symptoms of nausea, vomiting, epigastric discomfort, etc., and occasionally cause pancreatitis, esophagitis and esophageal ulcers, mostly occurring immediately after taking the drug in bed. Secondly, there will be maculopapular rash and erythema, a few can be exacerbated by urticaria, angioneurotic edema, etc., exfoliative dermatitis of the epidermis, anaphylaxis and asthma occurs, and it may cause hemolytic anemia, thrombocytopenia and other problems. Tetracycline absorbed by the human body and the body of calcium substances can be deposited in the bone, in the development of teeth mineralization period taking tetracycline tablets, can be bound to the tooth tissue to make the tooth color, but also can cause enamel hypoplasia. It is recommended to take this product need to be under the guidance of a physician or pharmacist, do not expose directly to sunlight or ultraviolet light during the medication, and consult a physician immediately in the event of erythema of the skin or other adverse reactions.