How Opioids Work And How They Impact The Body

Opioids are created naturally within the body and are commonly prescribed, but how do they work?

What Are Opioids?

Opioid is a term that originally specified a group of man-made Opiate-like drugs, Opiates being natural drugs created from the poppy plant. Recently the term has been adapted to cover both synthetic and natural drugs. This group is most commonly associated with its analgesic (pain relieving) effects and physicians commonly prescribe Opioids to patients dealing with moderate to severe chronic pain or overwhelming acute pain. The method through which your body uses Opioids grants them access to many different parts of your physiology.

How Do Opioids Work?

To understand opioids, it is useful to understand what parts of your body they interact with. Within your body, small proteins dot the outside of your cells. These proteins act as locks and will only open when a specific chemical keybinds to them. The nerves within the body have many receptors specifically for Opioids and they interact in different ways with different Opioids.

Mu-Receptor (MOR)

The majority of Opioids bind to these receptors, making them the focus of scientists in pursuit of developments and cures for Opioid use and abuse.

Kappa-Receptor (KOR)

KOR receptors play a role in receiving opioids and chemicals that regulate mood. This has led to studies linking addiction to other mental illnesses like depression and anxiety that can govern one’s mood.

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Delta-Receptor (DOR)

This receptor is less well studied than the previous two, but it functions similarly. Scientists are pursuing studies to reveal underlying connections between chronic pain and lasting mental illnesses involved with the DOR receptor.

Agonists and Antagonists

Within the classification of opioids, there are different types. Agonist is a general term for a chemical that can bind to and create a response with a receptor in the body. In terms of Opioids, these are the drugs most commonly associated with strong effects and common abuse. Codeine, Heroin, and Fentanyl all fall into the agonist category.

Opioid antagonists like Naloxone and Narcan occupy opioid receptors, blocking access to Opioids. These are commonly used in emergency overdose situations and are so aggressive that they will knock opioids off of their receptors and stop any further Opioid effects.

There are also partial and mixed agonist Opioids. These classifications refer to drugs that have Opioid effects, but their effects are not as powerful as full agonists.

Where Do Opioids Go?

If abused, Opioids can have negative effects on many different systems within the body, but there are three areas most commonly associated with Opioid use.

The Brain

Opioids bind to different parts of the brain to increase comfort and induce a sleepy feeling. They can also bind to the brain stem to relax breathing and fight off coughing. These effects help reduce stress in the body, which is why it produces its own endorphins.

Nervous System

Binding to nerves in the spinal cord and other pain sensing nerves throughout the body, opioids dull or fully remove sensations of pain. Once bound to a receptor, opioids essentially order a nerve to prioritize other signals over pain. If pain signals aren’t being sent, pain isn’t being felt.

Digestive Tract

A common side effect of opioid treatment regiments arises once opioids begin binding to the digestive tract. Opioid-Induced Bowel Dysfunction (OIBD) is a complication characterized by a suite of intestinal issues. Most commonly, Opioids cause constipation, but they can also cause reflux, abdominal pain, and more serious issues if use is prolonged.

Opioid Dependency

Your body produces its own Opioids in the form of endorphins. These chemicals produce runners high during long races and create the feel good effect after exercise in general. Because of the powerful effect of Opioids in the body, it only takes a little to achieve the desired effect, but if someone is a regular Opioid user, than this relationship is shifted out of balance.

As Opioids are used more frequently, the body becomes accustomed to their presence and effect. Like many other substances, a tolerance to the drug builds and more is required to achieve the same effect. Receptors become desensitized to the Opioids and as you take more, your body begins to produce less by itself. If you’re addicted to Opioids, your body will not function normally without them, creating a dependency. Without the presence of Opioids in the body, an addict will start to suffer from withdrawal.

Opioids are a serious group of drugs usually prescribed to handle serious issues. They are known for their addictive quality and ability to quickly form dependencies. If you or a loved one is struggling with Opioid abuse contact a treatment provider for rehab-related help.

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Michael Muldoon

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  • Michael Muldoon earned a B.A. in Media Studies from Penn State University, but instead of shifting into an academic career in social science, he has decided to put his skills to work in the pursuit of helping those struggling with addiction. He enjoys spending his free time at the climbing gym with friends.

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