NCI Dictionary of Cancer Terms

The NCI Dictionary of Cancer Terms features 8,413 terms related to cancer and medicine.

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A substance made from morphine. Heroin is very addictive, and it is illegal to use or sell it in the United States. It may be used outside the United States to treat severe pain. Heroin binds to opioid receptors in the central nervous system. It is a type of analgesic agent and a type of opiate. Also called diacetylmorphine hydrochloride and diamorphine hydrochloride.