When treating chronic pain, narcotic opioids should be considered if pain cannot be otherwise controlled. Although these medications can be dangerous and addicting, they can also be effective when used appropriately. An opioid is a chemical substance that has a morphine-like action in the body. The term opioid is derived from opium, which is an extract from the poppy plant. These agents have been available for centuries to relieve pain. Opioids work by binding to opioid receptors, which are found principally in the central nervous system and the gastrointestinal tract. The receptors in these two organ systems mediate both the beneficial effects, and the undesirable side effects. All of the opioids have similar clinical effects that vary from one another in potency, speed of onset, and duration of action. Both short-acting and long-acting formulations are available, as some opioids are used around-the-clock while others are used as needed for breakthrough pain.
One common mistake when treating chronic pain with opioid medications is using the short acting types of medication (e.g. Percocet, Morphine, Vicodin, etc.). While these medications are useful for acute pain, they are also associated with sedating and euphoric side effects. The short acting nature of these medications encourages overuse and the development of tolerance. Long-acting opioids may have fewer cognitive side effects and better control of chronic pain. Although no adequate long-term studies have shown their effectiveness in the treatment of chronic nonmalignant pain, and they are not approved for this use, they are often used for this type of pain management. Side effects may include GI upset, nausea, disturbed sleep, constipation, and addiction. Studies show about 5-15% of chronic pain patients using narcotic pain medications develop dependence. The following is a comprehensive listing of the broad classes of narcotics:
- Natural Opioids
- alkaloids contained in the resin of the opium poppy (morphine, codeine, thebaine, and oripavine).
- Semi-synthetic Opioids
- from the natural opioids (hydromorphone, hydrocodone, oxycodone, and heroin).
- Fully-synthetic Opioids -
(fentanyl, pethidine, methadone, and propoxyphene).
- Endogenous Opioid Peptides
- produced naturally in the body (endorphins, enkephalins, dynorphins, and endomorphins).
Tramadol (Ultram) is an atypical opioid that is a centrally acting analgesic, used for treating moderate to severe pain. It is a synthetic agent and analogue of codeine, and appears to have actions on the GABAergic, noradrenergic and serotonergic systems. Unlike most other opioids, Tramadol is not considered a controlled substance in many countries (including the U.S). An extended-release formula is available to treat moderate to severe chronic pain when treatment is needed around the clock.
The Opioid Controtroversy
Considerable debate exists about the use of opioids for treatment of chronic pain of non-cancer origin. Many physicians feel that opioids can play an important role in the treatment of all types of chronic pain, including non-cancer pain. Others caution against the widespread use of opioids noting problems with tolerance, loss of benefit with time, and escalating usage with decreasing function in many individuals. The use of opioids makes sense when the benefits outweigh the risks and negative side effects. Benefit is suggested when there is a significant increase in your level of functioning, when there is a reduction or elimination of pain complaints, when there is a more positive hopeful attitude and when side effects are minimal or controllable. The dilemma with the long term use of opioids is that while there is a role for opioids in chronic, non-cancer pain, it is well known that prolonged use of opioids may result in problems including tolerance, hyperalgesia (abnormal pain sensitivity), hormonal effects (decreased testosterone levels, decreased libido and sex drive, irregular menses), depression, and suppression of the immune system. While opioid treatment may be prescribed to reduce pain and improve function, the treatment may actually result at times in just the opposite.