Prescription narcotics, also none as narcotic analgesics or opioids, are the most used and abused medicines today.
Opioids are agents that binds to Opioid receptors found in the central nervous system and the gastrointestinal tract and cause a state of euphoria.
Opioids were used as early as 4000 BC by Greeks and Romans for the treatment of pain and for recreational use.
Hippocrates and Galen used opioids to treat headache, asthma, and melancholy.
1.5 million Americans are dependent on opioids or have abused opioids.

There are four classifications of Opioids:
Endogenous opioid peptides—naturally produced in the body
Opioid alkaloids—Morphine, codeine, Thebane
Semi-synthetic opioids—Heroin, oxycodone, hydrocodone, and oxymorphone
Full synthetic—Methadone and Buprenorphine. Fentanyl is a full synthetic drug 80 times stronger than Morphine and is measured in micrograms instead of milligrams.

Opioids can be taken orally, injected, subcutaneous, nasal, or smoked
Side effects include: Nausea, vomiting, drowsiness, dizziness, headache, low blood pressure, low heart rate, itching, dry mouth, urinary retention, constipation, constricted pupils, confusion, hallucinations, delirium, low temperature, biliary spasm, muscle rigidity, flushing, bowel obstruction, ileus, respiratory depression, and death.
Chippers are occasional light recreational users of opioids
Morphine is named after Morpheus the God of dreams
Withdrawal symptoms include: Dysphoria, anxiety, eye tearing, runny nose, goose bumps, sweats, nausea, vomiting, cramping, and deep pain.

Slang Terms:
Morphine—Miss Emma, Mister Blue, Morf
Heroin—Hazel, Hombre, Al Capone, Antifreeze
Oxycodone— Ocs, ocean cities, oxies
Methadone— Fizzies, Chocolate chip cookies

Tolerance is the tendency of the body to adapt to the presence of opioids; this adaptation makes it necessary to use ever-increasing doses of opioids in order to achieve the same effects.
Dependence is the tendency of the body to manifest a characteristic and unpleasant withdrawal syndrome if regular doses of opioids are abruptly discontinued after tolerance has developed.
Addiction is a psychological attachment to certain effects of opioids (such as the euphoria that many people experience when the drugs are taken in sufficiently large doses) that drives some people to take the drugs even when they are not medically necessary, and even when their use of the drugs becomes self-destructive. Dependency and the unpleasantness of withdrawal can work to maintain addiction, although they do not cause it.