Blocking drugs do not affect the results of the fourth generation HIV test. Generally speaking, Zidovudine, Lamivudine, Nevirapine and other AIDS blocking drugs only try to inhibit the virus infection and reduce the chances of contracting AIDS, not to prolong the window period, that is to say, after taking the blocking drugs for the fourth-generation HIV test, it will not affect the results of the test. Taking blocking medication within 72 hours of high-risk behavior can block viral infection and replication, and after the 14-day window period, the fourth-generation test can be used for screening; if the result is negative, the fourth-generation test needs to be conducted 6 weeks later, and HIV infection can be ruled out if the result is still unchanged. Blocking medication plays a very important role in reducing HIV infection, and should be taken in a timely manner once high-risk behaviors have occurred.