Opioids and Gut Issues

Written by: Kevin Cann

            An opioid is a chemical messenger that bonds to an opioid receptor.  A well known group of opioids are known as our endorphins.  These are the “feel good” neurotransmitters that come in after a workout.  They are also associated with our ability to manage pain.  In fact, pain medications work on our opioid receptors to decrease the sensation of pain and increase our tolerance to it.  Opioid receptors are found in the brain, spinal cord, and gastrointestinal tract.

Opioid receptors being in the gut tells us that they play a role in gut function.  One of the biggest side effects of opioid analgesics (fancy way of saying pain meds) is constipation.  These pain meds, which act upon our opioid receptors, cause a disruption to peristalsis (our stomach contractions that allow us to digest food) and also blocks fluid secretion (Holzer, 2007).  Modern medicine is attempting to find ways to enact upon the opioid system to manage pain, but not to interfere with the gut.

Low-dose naltrexone has shown promise in preclinical studies.  Low-dose naltrexone has the ability to block excitatory opioid receptors without affecting inhibitory opioid receptors.  In one study 42 patients were given .5mg of LDN for 4 weeks.  The mean weekly number of pain free days increased with no adverse reactions (Kariv, 2006).  There are two opioid receptors that play a role in gastrointestinal motility, delta and mu.  The opioid receptor mu directly affects the myenteric plexus.  The myenteric plexus is a part of the enteric nervous system that controls the activities of the digestive tract.  Therefore, anything that enacts upon these receptors has the ability to cause constipation (Herndon, 2002).

A study done on mice showed that during intestinal inflammation there was an increase in the amount of active mu opioid receptors (Puig, 1998).  Over time opioid tolerance can become an issue.  This is when pain medications need to be increased in dosage or substituted for other medications.

The question I would like to ask is if we are under chronic inflammation and our opioid receptors are increasing in number; will this lead to an increase in desiring foods that will react upon our opioids such as sugar, or other opioid stimulating activities?  Ever know that person that is addicted to running?  Endurance athletics is known to increase intestinal permeability (Buckley, 2009).  Was the intestinal permeability present before that led them to a behavior that would increase production of opioids and then it became cyclical with one affecting the other?  Think about that same person’s diet; are they in love with their carbohydrates?  Also, opiate addicts will eat the same amount of calories as non-addicts, but will choose foods high in sucrose and low in nutrients (Morabia, 1989).  Is intestinal permeability a culprit of food cravings?

Gluten and casein have the abilities to create morphine like compounds.  Are the people under chronic inflammation the ones who become addicted to these foods?  Is that the person that you know that is in love with their cheese or their bread?  Hippocrates had it right, “All disease begins in the gut.”  There has to be a reason that our brain and gut communicate via the thickest nerve in our body and share receptors for the same neurotransmitters.  The gut also contains the enteric nervous system which can work on its own without help from the brain.

This is where other diets fail.  Other diets fail to look at health and weight loss from the inside out.  They are mostly focused on what goes in from the outside.  How can we make proper food choices without understanding how that food reacts in our body?  We have enough inflammation caused from poor sleep, low vitamin D levels, stress from jobs, family, money, stimulants, and others that we do not need to be increasing inflammation anymore.  This is where “Everything in moderation” does not work.  Health and weight loss are not a simple math problem, but instead a series of complex chemical reactions that we have yet to fully understand.  In the meantime, sleep well, take some deep breaths, get some sun, and eat adequate veggies to feed the gut the nutrients it needs to flourish, high quality protein sources for amino acids our neurotransmitter precursors, and healthy oils for brain healthy fats (animal meats contain some brain healthy fats as well).








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  1. eema.gray says

    My husband is 54. When he was a very young man in the Army, he took part in the attempted rescue of American hostages in Iran, the attempt that ended in burning helo’s in the desert. He was burned very badly and was given a 6X overdose on morphine over the course of about 6 hours. Essentially, a very few medics were working on far too many men and weren’t properly marking who had gotten doses when. He was kept on morphine for the first few weeks of his burn treatment as well.
    I’m pretty well convinced at this point that all of that morphine messed up his brain and gut chemistry. He’s mostly off gluten now, after six months of work, but he is literally addicted to sugar. He says it helps him control the desire for morphine, 30 plus years later. Any ideas on how to get him off sugar, heal his gut, and heal his brain?

    • kevin cann says

      Sorry to hear that, I am glad he is alive! I am not sure where in the country you live, but finding a practitioner that deals with neurotransmitter issues would be my first step. In San Fransisco there is a place called Recovery Systems and it is run by Julia Ross. They have amazing results dealing with these issues. Her site is http://www.moodcure.com. She has some good books and for more understanding of the issues check out Kenneth Blum’s research on Reward Deficiency Syndrome. It just comes down to recognizing imbalances biochemically and correcting them.

  2. Samantha says

    I’ve recently been looking into low dose naltrexone for Hashimoto’s. Do you know much info about LDN and autoimmune diseases? Thanks!

  3. Jenny says

    My husband uses oxycontin for chronic pain and has severe constipation from the opioid. Is naltrexone better than Relistor for treating constipation from opioids?

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