The correct name of Doxycycline Tablets is Doxycycline Hydrochloride Tablets, which is a tetracycline antibiotic, and its main action is anti-infection. The main mechanism of action of Doxycycline Hydrochloride Tablets is to interfere with the protein synthesis of bacteria, and play an anti-infective role. Doxycycline Hydrochloride Tablets are mainly used for the treatment of rickettsial diseases such as epidemic typhus, endemic typhus, Rocky Mountain Fever, Scrub typhus and Q fever; Mycoplasma spp. infections; Chlamydia spp. infections such as psittacosis, venereal disease, lymphogranulomatosis, non-specific urethritis, salpingitis, cervicitis, and trachoma; return to the fever; brucellosis; cholera; rabbit fever; bubonic plague; and chancre. Adverse reactions include nausea, vomiting, abdominal pain, diarrhea, urticaria, angioneurotic edema, anaphylactic purpura, thrombocytopenia, neutropenia, headache, vomiting, optic nerve papillae edema, dry mouth, pharyngitis, xerostomia, and lingual inflammation. It is contraindicated in patients with a history of hypersensitivity to any of the tetracyclines. Be careful not to drink alcohol during the use of the drug, avoid self-addition or co-administration of other antibiotics, pay attention to the observation of the efficacy of the treatment to avoid the occurrence of adverse reactions.