Blood-borne infection is a common complication of the self-administration of drugs of dependence by the intravenous routes. British drug addicts are notorious for their disregard of even the most elementary hygienic precautions. They will use dirty needles and syringes, which are often being used by other addicts as well. They may use unboiled tap water or even lavatory pan water to dissolve the drug for self-injection. They may not clean the skin before injection and in desperate moments may inject themselves through a number of layers of clothing.