Method for preparing anti-infective agent long-acting injection

The invention provides a method for preparing anti-infective agent long-acting injection, and relates to an anti-infective agent long-acting injection. Each 1,000 mL of injection comprises the following components: 10 to 500 g of anti-infective agent, 100 to 900 g of cosolvent, 0 to 100 g of blocker, local anesthetic or stabilizer, and the balance of oil solvent. The method method for preparing the injection comprises: 1, dissolving 10 to 500 g of anti-infective agent in 100 to 900 g of cosolvent and mixing the two well; 2, adding 0 to 100 g of blocker and / or local anesthetic or stabilizer; and 3, adding the oil solvent till full volume and mixing thoroughly to form a uniform system. The method has antibacterial medicaments dissolved in the cosolvent first and then uniformly dispersed in the oil solvent capable of dissolving the antibacterial medicaments mutually so as to prolong the absorption rate of organisms to the medicaments, thereby maintaining the effective concentration of the medicaments in the organisms for a long time, achieving the long-acting effects and reducing the toxic effects of the medicaments.