Failure of blocking medications may be related to other factors such as inappropriate timing of medication, poor medication compliance, and the presence of bad habits. 1. Inappropriate timing of medication: blocking medication taken at the right time has a higher success rate. For example, the sooner the AIDS blocking drug is taken, the better, preferably within 24 hours of occupational exposure or high-risk sexual behavior. Taking it later is more likely to result in failure of the blockade. Hepatitis B pregnant women are generally recommended to take the drug between the 26th and 28th weeks of pregnancy for mother-to-child blockade, and other times may lead to failure of the blockade. 2. Poor medication compliance: the blocking drug should be used according to the doctor’s instructions, if the patient’s medication compliance is poor, there is a leakage of the drug or the dose of the drug does not meet the requirements, and so on, it is also easy to block the failure of the situation. 3. Other: if in the use of blocking drugs at the same time, in order to maintain good habits, such as unclean sexual behavior, may lead to re-infection, which in turn leads to the failure of the blocking situation. There are many reasons that lead to the failure of drug blockade, once the failure, it is recommended to go to the hospital in time, and actively cooperate with the doctor for treatment.