Repeatedly taking the blocking medication, as long as it is not too frequent, generally does not produce drug resistance. Generally, blocking drugs refer to AIDS blocking drugs, which belong to a combination of concentrated antiretroviral drugs, including tenofovir, emtricitabine and raltegravir, etc., and are mainly used for preventing patients from high-risk exposure to AIDS after high-risk sexual behaviors. The success rate of the blockade is very high if the patient takes the medication in full as well as regularly for the prescribed period of time. In addition, the optimal time to take the blocking medication is 2 hours after the occurrence of high-risk sexual behavior, and it is generally recommended not to exceed 24 hours. However, as long as it is taken within 72 hours, there is still some chance of success. In addition, blocking pills generally need to be taken for 28 consecutive days, taking medication has certain side effects, need to be under the guidance of a specialist, not blindly take the medication on their own.