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
-
in the
relief of severe chronic pain, e.g.
-
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.
* page last updated 5/20/2008
