Why do opiates cause constipation: The study of the receptology of opiates is certainly complex because advanced from a biological and pharmacological point of view but decisive for the understanding of phenomena such as pain, addiction or pleasure. In fact, the stimulation of these receptors by opiates causes various cellular responses. Each receptor and its subtypes are associated with particular clinical effects.

Why do opiates cause constipation
Why do opiates cause constipation

Why do opiates cause constipation: One of the side effects of opiates is constipation.

As much as I understood quite well that antibiotics cause diarrhea, since they attack the digestive system, as much, at first, I did not quite figure out why opiates could cause constipation.

Why do opiates cause constipation

In fact, it’s pretty simple.

Why do opiates cause constipation
Why do opiates cause constipation

Opiates relax the muscles. As a result, the transit of food within the digestive system takes place more slowly. Now, in the digestive system, water is drained of food into the interior of the body. It dries up the food bolus. This is what makes that the stool is not in the form of diarrhea permanently. When someone takes morphine since the food bowl stays longer in the digestive system, the drainage of the water takes place for longer, and logically it is more dried out. The stools that form are then drier and more compact.

And since the sphincter muscles are more relaxed, they will be less able to force to expel firm stools.

It may also be that the nerves detecting the right moment to induce contractions to expel stools are less illness signal is released. And at that moment, a compact plug would already have had time to form.

And as the transit is done more slowly, and also, the stools can not get out; there may be an accumulation of partially digested foods as well as a stool. Two or three meals do not have time to be evacuated rectum in the form of seats. It may also cause intestinal occlusion (but it is poorly documented, so it should be rarer).

The fact that the person is lying or sitting all day should not help either. With muscles that are more relaxed, the sitting position (and possibly the extended position too) will probably favor the creation of a plug (wider area) near the entrance of the anus. This will make eviction much more challenging.

Perhaps the slowing down of transit is partly desired by the organization.Maybe the center of the body is dehydrated. So, by doing this, he may be trying to take as much water as possible from food. But hey, it’s unlikely anyway. It must be only the problem of relaxation of the muscles that must generate this phenomenon.

All this mechanism is known to orthodoxy. So I do not do original work here. But that’s what comes next which is interesting.


Opioids almost always cause constipation. It can become extremely unpleasant, even dangerous. A laxative is therefore systematically prescribed in prevention by doctors.

It is advisable to take this laxative from the first taking of the opioid treatment and throughout the duration of the treatment. The dose of laxative is adapted according to each person and according to its effectiveness.

If the laxative treatment is effective (1 to 2 daily stools), do not stop it. In the case of diarrhea (more than three regular seats), decrease the dose of laxative with the agreement of your doctor. Consult your doctor if you have less than one bowel movement per week.

If you wish, you can benefit from a consultation with a dietician. She can help you set up menus and adapt your diet to limit the risk of constipation.

We recommend reading the article: Top 10 natural laxatives against constipation

Some simple measures restrict the potential for constipation:

Why do opiates cause constipation
Why do opiates cause constipation
  • Drink very often small quantities of liquids: water, fruit juices, herbal teas, dairy products, soups, coffee, tea, milk … (1.5 to 2 liters per day);
  • Consume raw and cooked fruits and vegetables in all forms (fresh, frozen, canned or dried);
  • Limit food slowing down transit (rice, cooked carrots, bananas);
  • Maintain physical activity as much as possible;
  • Massage your stomach;
  • Keep comfortable conditions to go to the bathroom and go there regularly, even if you do not feel like it.

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