What is "flashblood"

Flashblood (also called flushblood) 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 (a "high") 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.

After injecting herself with heroin using a syringe, the user will extract approximately 5 ccs of blood from her vein, which another user will inject into her vein. It is unclear if there is enough heroin in the small volume of injected blood to get high or if the high that many users claim is a result of traces of the heroin that had been injected by the user, or if the high is simply the result of the placebo effect. Sharing blood in this manner carries a very high risk of transmitting viruses such as hepatitis and HIV, which are prevalent among injection drug users in East Africa.