To Your Health: Opioids and the Brain

In this article, I will try to explain what opioids are and how they work in the brain. First a disclaimer: As I am not a physician, neuroscientist, or toxicologist, I am relying on the knowledge and work of others who are in those fields. It is clear from my scouting of the information available to the public that most of the information is not about how opioids affect the brain, but about how serious the epidemic of opioid use is in Maine and the rest of the country.

Opioids are synthetic pain drugs, some of which are prescription medications. Certain synthetic pain medications, such as methadone and fentanyl, are illicit drugs; oxycodone and hydrocodone are prescribed medications. Opiates, on the other hand, are naturally occurring drugs, such as heroin and opium, or pain medications, such as morphine and codeine, all of which come from the opium poppy. Overuse and misuse of both opioids and opiates can result in dependence, addiction and overdose.

One can find multiple references in print and online and YouTube videos that detail the very serious consequences of opioid addiction, from loss of family, financial stability and jobs to loss of life. In 2015 in Maine there were 272 drug related deaths, 111 of which were attributed to prescribed opioids, not street opioids. In 2016, the deaths from overdoses climbed to 376.

In the fishing industry, the long days, continued standing, and physical eff ort take a toll on the body. Fishermen develop aches and pains in the knees, hips, and shoulders that can progress to chronic pain over the years. Anyone with pain generally seeks ways to control it. When over-the counter medications such as Tylenol do not ease the pain, people may seek prescribed painkillers such as OxyContin®, Percocet® or other opioids.

Why are these opioid chemicals so dangerous? What happens to a brain that uses these drugs?

Our brain cells manufacture their own opiates, called endorphins, in response to stress or intense experiences. These endorphins then attach to opioid receptors on nerve cells in the brain and trigger the release of dopamine. Dopamine reduces the perception of pain and enhances the perception of pleasure. Being free of pain and feeling happy is a good state to be in. This natural interplay between the two chemicals maintains a balance, or homeostasis, in our bodies.

Over the years, pharmaceutical companies have developed chemicals that mimic our own endorphins (endogenous opiates). The chemicals brought into the body from outside are known as exogenous opioids (if synthetic) or exogenous opiates (if naturally occurring – for example, heroin).

Think of the two types of chemicals as competitors in a simple game. The exogenous opioids and opiates compete with endogenous opiates to gain access to the nerve cell receptors.

There are three distinct stages of progression when using a synthetic opioid or an opiate like heroin. The first is the development of tolerance to the exogenous opioid. The opioid hooks into opioid receptors on the nerve cells and produces a physiological result, for example, reduced perception of pain. With continued use, it takes more of that opioid to create the same amount of perceived pain reduction. At this point, the person taking the opioid often wants a higher dose in order to gain the same result. If a user were to realize that he or she had developed a tolerance to the opioid, the user could be weaned from the drug and seek less problematic drugs. In sailors’ terms, the boat could still right itself at this point.

As tolerance increases, the user passes into a stage of physical dependence. This stage is characterized by a need for the drug in order to avoid the unpleasant symptoms of withdrawal. The drug use is what keeps the user “on an even keel” and the innate balance or homeostasis between endorphins and dopamine has been overruled. The opioid receptors in the nerve cells are now demanding the synthetic drug. The user feels that he or she has no choice but to seek to increase the dose and/or frequency of use in this stage. If the original introduction to opioids was through a prescription, then the user may hop from physician to physician to get more of the drug, or may turn to street drugs such as heroin.

What many might not know is that physical dependence can occur without progression to addiction and addiction can occur without passing through the physical dependence stage. Addiction is characterized by craving and compulsiveness without regard to the harm done to oneself, one’s family, friends and others. An addicted user who goes without the opioid is visibly sick. Addiction is recognized by many health care professionals as a disease.

Exogenous opiates and opioids reach opiate receptors and cause a physiologic change but other drugs can reverse or block those chemicals from reaching the receptors. Narcan® is now widely used by emergency responders to reverse overdoses of the opiate heroin. Suboxolone® is a combination drug which occupies the receptor enough to block the craving and also block the physiologic result, i.e., the reduction of the perception of pain and the increase of feelings of extreme happiness. This explanation is very basic, of course. There are numerous researchers, physicians, neurologists, sociologists, counselors and others working to learn how to stop the use of exogenous opioids and how to help users redefine their lives without drugs.

A few useful Web references for further information: https://science.howstuff