OxyContin. Percocet. Vicodin.
Morphine. You may have heard of these opioids
or known someone who has been prescribed them for severe pain. Last month, the FDA announced that it’s
requiring new safety labeling of opioid analgesics (painkillers) and
manufacturers to conduct additional clinical studies to assess the long-term
risks associated with these prescription medications. This announcement is in response to the
widespread issues of addiction, abuse, and misuse associated with these
narcotics (Liscinsky, 2013).
Opioids are psychoactive
chemicals that resemble compounds of the biosynthetic group benzylisoquinoline
alkaloids, which are produced by plants, such as the commonly known opium poppy
(Facchini, 1998). These drugs utilize
the receptors that are naturally bound by opioid proteins produced in the
central nervous system (CNS). The
naturally produced opioid proteins have a variety of functions including pain
relief and diarrhea prevention (Froehlich, 1997). There are three main types of opioid
receptors in the CNS, μ, δ, and κ (Mansour, 1988), all of which are part of the
G-protein receptor family (Coward, 1999).
Opioid drugs, such as Vicodin, bind to these same receptors and induce changes
in the cell that result in a variety of similar effects, typically pain relief
and euphoria.
Opioid drug addiction has been on the rise and
the number of deaths from unintentional overdoses has doubled since 2000. The volume of prescribed opioids has
increased sixfold since 1997 (Rosenblatt, 2012) and much of this has been
attributed to aggressive marketing of drugs like OxyContin for chronic pain
relief (Okie, 2010). The FDA’s decision
to step in and implement new regulations seems necessary, but will it
negatively impact the 100 million Americans suffering from chronic pain
(Institute of Medicine, 2011), who may be undertreated as a result?
REFERENCES
Coward P, Chan SDH, Wada HG, Humphries GM, Conklin BR. 1999
Jun. Chimeric G Proteins Allow a High-Throughput Signaling Assay of Gi-Coupled
Receptors. Analytical Biochemistry. 270(2):242-248.
Facchini PJ, Bird DA. 1998 Mar. Developmental
regulation of benzylisoquinoline alkaloid biosynthesis in opium poppy plants
and tissue cultures. In Vitro Cellular & Developmental Biology – Plant.
34(1):69-79.
Froehlich JC. 1997. Opioid Peptides.
Alcohol Health Res World. 21(2):132-136.
Institute of Medicine. Relieving Pain in America: A
Blueprint for Transforming Prevention, Care, Education, and Research
[Internet]. Washington, DC: The National Academics Press; 2011 [cited 2013
October 13]. Available from: http://www.nap.edu/catalog.php?record_id=13172.
Liscinsky M. 2013 Sep. FDA announces
safety labeling changes and postmarket study requirements for extended-release
and long-acting opioid analgesics. U.S. Food and Drug Administration
[Internet]. [cited 2013 Oct 13]. Available from: http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm367726.htm.
Mansour A, Khachaturian H, Lewis ME, Akil H, Watson SJ.
1988. Anatomy of CNS opioid receptors. Trends in Neuroscience. 11(7):308-309.
Okie S. 2010 Nov. A
Flood of Opioids, a Rising Tide of Deaths. NEJM. 363:1981-1985.
Rosenblatt RA, Catlin M. 2012 Aug. Opioids for Chronic Pain:
First Do No Harm. Annals of Family Medicine. 10(4):300-301.
Great post Manny! The interesting thing I've found about opioid addiction is its sheer power. I do tutoring at a GED facility targeted towards parolees, and it's kind of amazing how many of them have issues kicking an opioid habit, be it heroin or OxyContin. I found an interesting bit of research that suggests that heroin at least has nothing to do with striatal dopamine release (Watson et al. 2013). Normally, we associate with the dopamine release of a drug with why it's addictive, as dopamine is the "feel-good hormone." The use of heroin did not provide a dopamine release, and even a "rewarding" dose during times of craving did not trigger a dopamine release (Watson et al. 2013). However, the finding of heroin not causing dopamine release might suggest a different pathway, which might contribute to why opiate addictions are so hard to kick as opposed to other drugs that cause dopamine release.
ReplyDeleteWatson BJ, Taylor LG, Reid AG, Wilson SJ, Stokes PR, Brooks DJ, Myers JF, Turkheimer FE, Nutt DJ, Lingford-Hughes AR. 2013 Jul. Investigating expectation and reward in human opioid addiction with [11C]raclopride PET. Addiction Biology. DOI: 10.1111/adb.12073
I think there will be potential positive and negative impacts. The FDA’s new regulations might make doctors more reluctant to prescribe opioids to patients, even if they are suffering from chronic pain or other related conditions that require some form of analgesic. The stigma of possible drug abuse also makes such prescriptions look less attractive (Fields 2011). In the long term, however, there may also be positive effects. The new regulations and prompting of studies to assess long-term risks could provide information beneficial to chronic pain sufferers, especially if it impacts their future health.
ReplyDeleteFields HL. Feb. 2011. The doctor’s dilemma: opiate analgesics and chronic pain. Neuron 69(4): 591-594.