special subjects
Injection Drug Use
Introduction
Drugs may be swallowed, smoked, inhaled through the nose as a powder (snorted), or injected. When drugs are injected, their effects may occur more quickly, be stronger, or both. Drugs may be injected into a vein (intravenously), a muscle (intramuscularly), or under the skin (subcutaneously). Veins in the arms are typically used for intravenous injections, but if these areas become too scarred and damaged, some people inject drugs into other veins, including those of the thigh, neck, armpit or feet. (See also Overview of Substance-Related Disorders .) 