Flashblood is an intravenous drug administration technique used by recreational drug users in which an individual injects himself with blood extracted from another drug user, most commonly one who has injected heroin. The purpose of the technique is to experience substance intoxication or to help combat symptoms of drug withdrawal. The practice was first documented in an announcement submitted by Sheryl A. McCurdy, et al., in an October 2005 issue of BMJ. First reported to be practiced in Dar es Salaam, Tanzania, the practice had spread to other areas in East Africa by 2010.