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The Irony of Medicinal Opioid Use

Opioid use has skyrocketed as of late, which has many referring to the increase as an “Opioid Crisis”.  More than 90 Americans overdose on opioids a day1, and the worldwide rate is even more staggering. Not all of the deaths are caused by illegal drug use, like heroin, however, prescription opioids are also extremely addicting and dangerous, and its misuse alone leads to a yearly economic burden of $78.5 billion a year1.

While illegal opioids, like codeine, have been integral parts of pop culture, leading to increased backlash against those glorifying it, the real danger lies in opioids that are prescribed by medical professionals. In 2012, 2.1 million Americans suffered from prescription opioid abuse, almost four times more Americans that abuse heroin2. This abuse leads to an array of adverse effects, from abandoning responsibilities, depression, and death3. Opioid abuse has ruined, and is currently ruining the lives of millions, but why do so many people get addicted?

Opioids are extremely addictive, they lead to the release of dopamine and endorphins, which in turn leads to a sense of euphoria and pain control4. While some people abuse opioids due to the euphoria they experience, others become addicted because it failed at doing the job it was supposed to do; control pain. Physicians often prescribe persons with chronic pain, like cancer patients, opioids ,such as morphine, to control their pain. While opioids effectively help chronic pain patients deal with their pain, after long use it actually increases their pain sensitivity. In a study titled “Morphine-induced Hyperalgesia in Rats Tested on the Hot Plate”, Kayan, Woods, and Mitchell studied how long term morphine use affected rats pain sensitivity. They tested pain sensitivity by putting rats in contact with hot plates to measure how rapidly they responded, and concluded that morphine use leads to an increase in pain sensitivity5.  This is very peculiar, considering morphine, an opioid, is used to help patients with pain control, but actually leads to increases in pain later on. Increased pain control is a big factor in opioid addiction, as those with chronic pain coming off opioid use are more sensitive to pain, making their pain even more unbearable than the pre-opioid pain, and forces them to continue using opioids. This cycle of not being able to come off opioids is very dangerous. The longer one uses opioids, the higher their tolerance becomes to adequately control pain, and therefore the higher the chance that they accidentally overdose. Therefore, to end the cycle of opioid use, a way to decrease opioid-induced hyperalgesia must be found.

In “Mu Opioid Splice Variant MOR-1K Contributes to the Development of Opioid-Induced Hyperalgesia”, researches attempt to do just that- find a way to decrease opioid-induced hyperalgesia. The researchers were able to pinpoint the source of the hyperalgesia to MOR-1K receptors. To test confirm their source, they tested the hyperactivity and knockdown of the MOR-1K gene in rats. As they believed, the hyperactivity of the MOR-1K gene led to an increase in pain sensitivity, while a knockdown of the MOR-1K gene led to a decrease in pain sensitivity. Due to this conclusion, they believe creating a drug that acts as a MOR-1K antagonist, blocking the gene, would be an effective way to treat opioid-induced hyperalgesia6.

The Opioid Crisis is a very serious matter, and a large portion of this crisis is due to the dependence of prescription opioids. These prescription opioids are extremely difficult to get off of, due to their ability to increase pain sensitivity, leading to continued use. An effective way of decreasing this cycle of opioid use is by inventing an efficient MOR-1K antagonist, which will decrease opioid-induced hyperalgesia, and it turn allow people to use opioids and discontinue using them without acquiring an increase in pain sensitivity.

Work Cited:

1. Abuse, National Institute on Drug. “Opioid Overdose Crisis.” NIDA, 1 June 2017, www.drugabuse.gov/drugs-abuse/opioids/opioid-overdose-crisis.
2. Abuse, National Institute on Drug. “America's Addiction to Opioids: Heroin and Prescription Drug Abuse.” NIDA, 14 May 2014, www.drugabuse.gov/about-nida/legislative-activities/testimony-to-congress/2016/americas-addiction-to-opioids-heroin-prescription-drug-abuse.
3. Staff, familydoctor.org editorial. “Opioid Addiction: Signs & Treatment.” Familydoctor.org, 1 Mar. 2017, familydoctor.org/condition/opioid-addiction/.
4. “Opiate Addiction | What Are Opiates & Why So Addictive?” The Recovery Village, www.therecoveryvillage.com/opiate-addiction/#gref.
5. “Opioid-Induced Hyperalgesia.” Institute for Chronic Pain, www.instituteforchronicpain.org/understanding-chronic-pain/complications/opioid-induced-hyperalgesia.

6. PLoS ONE 2015 Oladosu.Pdf | Powered By Box, luc.app.box.com/v/neuroseminar/file/253291376129.