Laxatives: Depression's Friend Or Foe?

Depression and constipation are often linked, with up to a third of people with depression also suffering from chronic constipation. While some antidepressants are known to cause constipation, this does not explain all cases. Research has shown that the two conditions may be caused by the same glitch in neuron chemistry—low serotonin. A recent study on mice found that a shortage of serotonin in the neurons of the gut can cause constipation, just as a serotonin shortage in the brain can lead to depression. An experimental drug that raises serotonin levels in the gut and the brain may alleviate both conditions.

Depression and constipation are linked by low serotonin levels

Depression and constipation are closely linked, and both conditions have been connected to low serotonin levels. Serotonin is a neurotransmitter often dubbed the "happy chemical" due to its crucial role in happiness and well-being, as well as a range of other complex cognitive functions. It is involved in various biological processes, including blood clotting and digestion.

The gut, often referred to as the body's "second brain," contains more neurons than the spinal cord and utilises many of the same neurotransmitters as the brain. This similarity suggests a potential link between gastrointestinal issues and mental health.

Research has found that a serotonin shortage in the neurons of the gut can lead to constipation, just as a serotonin deficiency in the brain is associated with depression. A study conducted on mice revealed that a reduction in serotonin levels in the gut resulted in a decrease in the overall number of neurons, deterioration of the gut lining, and slower movement through the gut, leading to constipation.

Additionally, people with depression often experience gastrointestinal distress, with up to a third of individuals suffering from chronic constipation. This comorbidity significantly reduces their quality of life. While certain antidepressants are known to cause constipation, they do not account for all cases.

The link between depression and constipation may lie in the gut's serotonin levels, as neurons in the gastrointestinal system also utilise serotonin. A treatment that raises serotonin levels in both the gut and the brain may offer relief from constipation and depression simultaneously.

Furthermore, promoting factors such as a healthy diet and addressing mental health issues may help alleviate digestive problems associated with low serotonin levels.

Antidepressants can cause constipation

Antidepressants can be an effective treatment for depression, but they can also have side effects. One of the most common side effects of antidepressants is constipation. This is particularly true of tricyclic antidepressants such as Elavil (amitriptyline) and Norpramin (desipramine). These drugs block the action of the neurotransmitter acetylcholine, which slows the muscular contractions that propel waste matter through the digestive tract and dries out the intestinal secretions that lubricate the passage of feces, resulting in constipation.

Although constipation is rare with newer medications like selective serotonin reuptake inhibitors (SSRIs), it is still possible to experience irregularity with some of these agents as well. It is important to note that antidepressant-induced constipation can be uncomfortable, but there are strategies to find relief. Consuming prunes or bran cereal, drinking plenty of water, eating high-fiber foods, getting regular exercise, and taking fiber supplements can all help alleviate constipation. If self-care strategies do not provide sufficient relief, it is important to talk to a doctor about other treatment options.

Constipation can be treated with laxatives

Constipation is a common issue that can be treated with laxatives. Laxatives are a type of medicine that can treat constipation by increasing stool motility, bulk, and frequency. They are available over the counter at pharmacies and supermarkets, as well as by prescription from a doctor. It is important to understand how laxatives work and how to use them safely, as misuse or overuse can lead to problems, including chronic constipation.

There are several types of laxatives, including bulking agents, emollient laxatives, osmotic and hyperosmolar laxatives, and prescription laxatives. Bulking agents, such as fiber, are the most commonly recommended type of laxative for normal and slow-transit constipation. They work by increasing the water content and bulk of the stool, aiding its movement through the colon. However, it is important to increase fiber intake gradually and ensure adequate hydration, as fiber can cause abdominal cramping, bloating, or gas.

Emollient laxatives, also known as stool softeners, contain docusate, which helps to "wet" and soften the stool. They are often used by individuals recovering from surgery, women who have recently given birth, or those with hemorrhoids. Osmotic and hyperosmolar laxatives, such as Fleet Phospho-Soda and polyethylene glycol (Miralax), draw water into the intestine, softening the stool and making it easier to pass. Adequate hydration is crucial when using these laxatives to prevent gas and cramps.

Prescription laxatives, such as guanylate cyclase-C agonist laxatives, promote regular bowel function by increasing water content and gastrointestinal movement. However, they carry a risk of diarrhea, especially in pediatric patients. Stimulant laxatives, such as bisacodyl (Correctol, Dulcolax) and sennosides (Ex-Lax, Senokot), work by stimulating the intestine lining and accelerating stool transit through the colon. While effective, they should not be used daily or regularly, as they may weaken the body's natural ability to defecate and cause laxative dependency.

It is recommended to start with a bulk-forming laxative and adjust as needed. If your stool remains hard, you can try adding an osmotic laxative. If your stool is soft but still difficult to pass, a stimulant laxative can be taken in addition to a bulk-forming laxative. It is important to speak to a healthcare professional if you are unsure about which laxative to use or if your constipation persists despite trying different types of laxatives.

Constipation can cause severe pain and sleep loss

Constipation is a common condition that generally isn't serious and doesn't last long. However, it can sometimes cause severe pain and sleep loss, leading to a reduced quality of life.

People with constipation often experience abdominal pain and discomfort. This pain can be due to not drinking enough fluids, which leads to dehydration and dry stool, making bowel movements more painful. In some cases, constipation may result in recurrent abdominal pain associated with irritable bowel syndrome (IBS). Severe constipation can also cause obstipation, where the colon becomes almost completely blocked, leading to an inability to pass gas or have a bowel movement.

Additionally, constipation can lead to diverticular disease, which affects the colon or large intestine. The increased bowel wall pressure caused by constipation can cause diverticula, or little pockets within the colon, to form. While these pockets are usually harmless, they can become inflamed if they break open.

In rare cases, constipation can be a medical emergency. For example, intense and constant abdominal pain combined with constipation could indicate a perforated intestine or stomach, intestinal obstruction, or mesenteric ischemia (blockage of blood flow to the intestine). Constipation with vomiting may signal fecal impaction, a dangerous condition where a large, hard mass of stool gets stuck in the colon.

Constipation can also contribute to sleep loss. Studies have found a link between disturbed sleep and bowel functions, with poor sleep quality leading to constipation. This relationship may be due to disruptions in biologic rhythms, such as those experienced by shift workers.

To alleviate constipation and its associated symptoms, it is recommended to stay hydrated, exercise regularly, maintain a healthy diet rich in fruits, vegetables, and fiber, and practice good bathroom habits, such as not ignoring the urge to go. If constipation persists or is accompanied by concerning symptoms, it is important to consult a healthcare provider.

Constipation can be caused by diet

While a single serving of a specific food is unlikely to cause constipation, a diet that is low in fiber can contribute to constipation. Foods that are low in fiber include eggs, onions, legumes, white bread, pizza dough, cakes, and baked goods. A diet that is high in fat can also lead to constipation.

A diet that is low in fiber can cause an imbalance between different food groups, which can contribute to constipation. Eating more fruits, vegetables, and whole grains may help relieve constipation. The Academy of Nutrition and Dietetics recommends 25 grams of fiber per day for women and 38 grams for men. After age 50, women need 21 grams and men need 30 grams.

In addition to increasing fiber intake, it is important to drink enough fluids to prevent dehydration. Dehydration can cause the body to pull moisture from cells and the colon, leading to dry and hard-to-pass stools.

Some people may also experience constipation when they eat foods that contain gluten, such as wheat, barley, and rye. Gluten intolerance or celiac disease can cause severe harm to the gut and should be avoided by those with the disease.

Dairy products, fried foods, and highly processed foods may also cause constipation for some people.

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