Thus, to maximize the high, "backdrawing" has become an essential, even ritualistic, part of drug use. The problem is that with "backdrawing" the user's blood contaminates virtually 100 % of the syringe and needle, so that effective sterilization becomes almost impossible. Use of either by another person can easily lead to transmission of disease.
這是由於打到血管外人體組織的毒品，會由肝臟吸收，減少快感，也因此，為了確認毒品一滴都不浪費，「倒抽」成了儀式般的不可或缺的動作。