Summary of Opioids

Opioids are commonly prescribed because of their effective analgesic, or pain relieving, properties. Studies have shown that properly managed medical use of opioid analgesic compounds is safe and rarely causes addiction. Taken exactly as prescribed, opioids can be used to manage pain effectively.

Among the compounds that fall within this class—sometimes referred to as narcotics—are morphine, codeine, and related medications. Morphine is often used before or after surgery to alleviate severe pain. Codeine is used for milder pain. Other examples of opioids that can be prescribed to alleviate pain include oxycodone (OxyContin—an oral, controlled release form of the drug); propoxyphene (Darvon); hydrocodone (Vicodin); hydromorphone (Dilaudid); and meperidine (Demerol), which is used less often because of its side effects. In addition to their effective pain relieving properties, some of these medications can be used to relieve severe diarrhea (Lomotil, for example, which is diphenoxylate) or severe coughs (codeine).

Opioids act by attaching to specific proteins called opioid receptors, which are found in the brain, spinal cord, and gastrointestinal tract. When these compounds attach to certain opioid receptors in the brain and spinal cord, they can effectively change the way a person experiences pain.

In addition, opioid medications can affect regions of the brain that mediate what we perceive as pleasure, resulting in the initial euphoria that many opioids produce. They can also produce drowsiness, cause constipation, and, depending upon the amount taken, depress breathing. Taking a large single dose could cause severe respiratory depression or death.

Opioids may interact with other medications and are only safe to use with other medications under a physician's supervision. Typically, they should not be used with substances such as alcohol, antihistamines, barbiturates, or benzodiazepines. Since these substances slow breathing, their combined effects could lead to life-threatening respiratory depression.

Morphine

Morphine  is a highly potent opiate analgesic drug and is the principal active agent in opium and the prototypical opioid. Like other opiates, e.g. diacetylmorphine (heroin), morphine acts directly on the central nervous system to relieve pain, and at synapses of the nucleus accumbens in particular. Studies done on the efficacy of various opioids have indicated that, in the management of severe pain, no other narcotic analgesic is more effective or superior to morphine. Morphine is highly addictive when compared to other substances; tolerance, physical and psychological dependences develop very rapidly.

The word "morphine" is derived from Morpheus, the god of dreams in Greek mythology. He is the son of Hypnos, god of sleep.

Morphine is used legally:

• as an analgesic in hospital settings to relieve

  • pain in myocardial Infarction

  • pain in sickle cell crisis

  • pain after surgery

  • pain associated with trauma

• in the relief of severe chronic pain, e.g.

  • cancer pain

  • pain from kidney stones

  • severe back pain

• as an adjunct to general anesthesia

• in epidural anesthesia or intrathecal analgesia

• for palliative care (i.e. to alleviate pain without curing the underlying reason for it, usually because the latter is found impossible)

Morphine is a highly addictive substance, both psychologically and physically, with an addiction potential comparable to heroin.