Opioids are used medically for relief of pain. Morphine and codeine are derived from this. Heroin is processed from morphine and codeine. Opiates have been used medically and recreationally for centuries. Heroin was developed in 1883.
Opium is dark brown chunks or in powder form, generally eaten or smoked.
Heroin usually appears as a white or brownish power, dissolved in water for injection. Other opioid analgesics appear in capsules, tablets, syrups, elixirs, solutions and suppositories. Briefly stimulate the higher centres of the brain, then depress activity of the central nervous system. With high doses drowsiness progresses to deep sleep and breathing may become slower. Profound respiratory depression, resulting in death, may occur.