For centuries, humans have marveled at the painkilling and euphoric effects of opioids. In 3400 B.C., the Sumerian people who occupied what is now Iraq referred to the native poppy plant as Hul Gil, or the “plant of joy.”
Some 5,000 years later, scientists are unraveling exactly how opioids exert their effects on the brain and body.
Your Brain on Opioids
While different opioids vary in potency and chemical composition, they all have similar physical effects.
In a nutshell, opioids reduce the transmission of pain signals in the brain and spinal cord. In doing so, the drugs also decrease brain activity, which slows your breathing and heart rate and makes you sleepy.
Opioids exert these effects by attaching to tiny proteins on the surface of nerve cells in the brain, spinal cord and other parts of the body. These proteins are known as opioid receptors.
Despite their name, the opioid receptors in our brains weren’t intended for drugs. The microscopic docking stations are actually targets for endorphins, natural “feel good” chemicals that our body produces in response to stress, fear, pain and exercise.
Because of their similar chemical structure, opioids are good at impersonating endorphins but they’re much more sinister than their natural counterparts.
While the body only releases tiny amounts of natural endorphins, opioid drugs overwhelm the brain’s pain pathways. In doing so, the potent chemicals unleash a host of unpleasant physical effects.
Common opioid side effects range from minor problems such as nausea, vomiting and itching to serious complications, including respiratory depression, coma and death. Continuous use of the drugs often leads to physical dependence and opioid addiction.
How Opioid Dependence Develops
With repeated use, opioids trigger predictable changes in brain chemistry.
To counteract the slowing effects of opioids and restore balance, the brain begins ramping up the activity of certain neurons. One way it does this is by producing more of a chemical called noradrenaline, which stimulates breathing, blood pressure and alertness.
At the same time, opioid receptors become less sensitive to the drugs, and a person will require more of the drug to achieve the desired effects. This is known as tolerance.
Tolerance is also marked by uncomfortable opioid withdrawal symptoms when a person stops taking the drugs or reduces their normal dose. Without the presence of the opioids to counterbalance the brain’s amped-up state, a person will experience anxiety, muscle cramps, nausea, vomiting and other distressing symptoms.
Tolerance can develop rapidly — in as little as a few days or weeks. To avoid withdrawal symptoms, people often increase their opioids use. This can create a vicious cycle that’s hard to break.
Fortunately, opioid dependence is not a permanent condition. Within several days to weeks of stopping an opioid, a person’s brain will return to its normal level of functioning.
But other brain abnormalities stemming from opioid use are much more difficult to overcome. With repeated use, opioids rewire the brain’s reward pathways. When this occurs, a person will develop a subconscious drive to seek and use opioids, no matter the cost.
Why Are Opioids So Addictive?
The biology of addiction is complex. Unlike opioid dependence, which resolves within days to weeks, opioid addiction is a long-lasting brain disorder that can cause strong drug cravings months or even years after a person has quit using the drugs.
Opioids trigger addiction in people by hijacking the brain’s reward center, a primitive part of the brain that motivates us to repeat behaviors that make us feel good.
In a healthy brain, healthy behaviors are reinforced. When we experience something pleasant, such as sex, food or socializing, our brain releases a chemical called dopamine. This chemical activates the limbic reward system that marks the experience as something good that we should do again.
Opioids, however, release enormous amounts of dopamine that overload the brain’s reward system causing an intense and unnatural euphoria. Once this experience is seared into the brain, it takes precedence over everything, including food, friends, family and work.
Uncontrollable cravings drive the person to seek more opioids, and rational thinking is blunted by the urges.
There no easy way to turn off an addiction. In a 2017 interview with the Portland Press Herald, Dr. Ruben Baler, a neuroscientist with the National Institute on Drug Abuse, compared having an addiction to knowing how to ride a bicycle.
Imagine, for an instant, trying to unlearn how to ride a bicycle. The activity is so firmly fixed in your brain that chances are you wouldn’t be able to forget how to do it. A substance use disorder is similarly ingrained. But unlike bike riding, it’s also accompanied by compulsive urges and painful physical reactions when you don’t use the drug.
Can Rehab Fix an Opioid-Addicted Brain?
While opioid addiction is a chronic and recurring disease of the brain, recovery is possible. Detox, which is usually the first step in treating an opioid addiction, can help you through the withdrawal process.
After that, medications such as buprenorphine can stabilize your brain chemistry while counseling and behavioral therapy teach you the skills to cope with cravings and other facets of addiction.
Evidence shows that this combination approach, which is known as medication-assisted treatment, is the most effective way to successfully conquer an opioid addiction. Because of the significant risk of relapse, continuing support through self-help groups, such as Narcotics Anonymous, and other aftercare services are also a critical component of opioid addiction treatment.
Author
Content Writer,
DrugRehab.com
As a former journalist and a registered nurse, Amy draws on her clinical experience, compassion and storytelling skills to provide insight into the disease of addiction and treatment options. Amy has completed the American Psychiatric Nurses Association’s course on Effective Treatments for Opioid Use Disorder and continuing education on Screening, Brief Intervention and Referral to Treatment (SBIRT). Amy is an advocate for patient- and family-centered care. She previously participated in Moffitt Cancer Center’s patient and family advisory program and was a speaker at the Institute of Patient-and Family-Centered Care’s 2015 national conference.
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