7 Important Facts About Constipation
in Dialysis Patients
Causes of Constipation in Dialysis Patients and What to Know About Laxatives and Herbal Products
Constipation in dialysis patients can develop because of dietary and fluid restrictions, certain medications, reduced physical activity, and other health conditions. Assessment involves reviewing bowel habits, any products being used, and the patient’s dialysis plan together. The ingredients in a constipation medicine also matter when kidney function is severely impaired.
This article provides general information, primarily for adults receiving regular hemodialysis. Children, pregnant patients, and people receiving peritoneal dialysis may need additional assessment. Tell the healthcare team about constipation that is new, becomes progressively worse, or occurs alongside other symptoms.
What Causes Constipation in Dialysis Patients
Constipation can have several contributing causes. Rather than attributing it directly to the dialysis machine, the assessment considers diet, medications, daily routines, and other medical conditions.
Dietary Changes and Fluid Restrictions
Changes in eating habits and an inadequate fiber intake are important contributors to constipation in dialysis patients. As kidney function declines, potassium and phosphorus intake may need to be controlled. This can mean limiting certain vegetables, fruits, legumes, and whole grains. However, restricting these foods too heavily without identifying suitable alternatives can reduce daily fiber intake, slow the passage of stool, and contribute to constipation.
Fluid restrictions may also contribute to harder stools and difficulty passing them, particularly in hemodialysis patients who produce less urine. Patients should not increase their fluid intake on their own to relieve constipation. Excess fluid can accumulate in the body, raise blood pressure, and place additional strain on the cardiovascular system.
A dietary plan to help prevent constipation should therefore be developed with the treating physician and a dietitian experienced in kidney disease. It should take account of potassium and phosphorus levels, the daily fluid allowance, and individual nutritional needs. The aim is to provide an appropriate amount of fiber while respecting the dietary restrictions required for dialysis treatment.
Medications
Some medications used during dialysis care can contribute to constipation. Medicines prescribed to manage mineral imbalances associated with kidney failure, treat anemia, or control other health conditions may affect bowel function and make stools harder to pass.
Phosphate binders, some potassium binders, and oral iron preparations are among the medicines that may cause constipation. Opioid pain medicines, certain allergy medicines known as antihistamines, and other drugs that slow intestinal movement can also contribute.
The effects vary between medicines and between patients. The active ingredient, dose, route of administration, length of treatment, and individual patient characteristics may all influence whether constipation develops. Medication-related causes of constipation in people with kidney disease are also discussed in BC Renal’s guidance on managing constipation in chronic kidney disease.
Constipation that begins after starting a new medicine or changing the dose of an existing one should be reported to the treating physician. Patients should not stop a prescribed medicine, reduce its dose, or switch to another treatment on their own because of constipation.
If necessary, the physician can review the medication regimen and possible side effects before adjusting treatment. This helps address constipation while allowing medicines needed for dialysis care to continue to be used safely and effectively.
Reduced Activity and Toilet Habits
Lower levels of daily physical activity can contribute to constipation in dialysis patients. For people receiving hemodialysis, scheduled treatment sessions, fatigue afterward, and long periods spent sitting may limit opportunities to move. Reduced activity can slow intestinal movement and lengthen the time stool takes to pass through the bowel, making constipation worse in some patients.
Activity that matches the patient’s physical condition and the physician’s advice may help support regular bowel function. Short walks and more movement throughout the day may also benefit general health. The type and intensity of exercise should be chosen with the patient’s age, cardiovascular health, mobility, and other medical conditions in mind.
Irregular toilet habits can also play a significant role. Repeatedly delaying a bowel movement because of travel to the dialysis center, treatment times, or other commitments may disrupt the usual bowel routine over time. When stool remains in the colon for longer, more water is absorbed from it, making it harder.
To help prevent constipation, patients may be encouraged to establish a regular toilet routine, respond to the urge to pass stool, and make use of the bowel’s natural increase in activity after meals. Excessive straining and spending long periods on the toilet trying to pass stool should be avoided.
If dialysis sessions or transport arrangements interfere with toilet habits, the healthcare team should be told. An assessment of constipation should consider daily activity and toilet routines alongside diet and medication use.
Other Medical Conditions
Constipation in dialysis patients can have causes beyond kidney failure and dialysis treatment. Other chronic illnesses, hormonal disorders, and digestive conditions may affect intestinal movement, causing constipation or worsening existing symptoms.
Diabetes is one condition that deserves consideration. Over time, diabetes can damage the nerves that regulate digestion in some patients. When diabetes affects the autonomic nervous system, intestinal movement may slow and stool may take longer to pass through the bowel. This should be considered when investigating constipation, particularly in people who have both diabetes and kidney failure.
Hypothyroidism, or an underactive thyroid, is another possible contributor. Low thyroid hormone levels can slow the body’s metabolic processes and intestinal movement. This may lead to less frequent bowel movements, harder stools, and difficulty emptying the bowel.
Problems with pelvic floor muscle coordination can also prevent the muscles needed for a bowel movement from working together properly. Affected patients may feel the urge to pass stool but struggle to empty their bowels completely, strain excessively, or feel little relief afterward.
Functional bowel disorders such as irritable bowel syndrome, along with other conditions affecting the digestive system, may also be associated with constipation. Further information about possible causes and their links with other medical conditions is available in the NIDDK’s information on the symptoms and causes of constipation.
Constipation that persists, becomes progressively more severe, or differs noticeably from a dialysis patient’s usual bowel pattern should be assessed by a physician. Blood in the stool, unexplained weight loss, persistent abdominal pain, or vomiting requires prompt medical assessment.
Identifying the cause involves considering the patient’s existing conditions, medications, eating habits, and relevant clinical findings together. This approach helps uncover underlying health problems that may contribute to the symptoms, as well as guiding symptom relief.
Recognizing the Symptoms of Constipation
Constipation in dialysis patients involves more than having fewer bowel movements. Hard stools, difficulty passing stool, and a feeling that the bowel has not emptied completely are also important symptoms. Assessment should therefore consider stool consistency and the difficulties a patient experiences as well as how often they pass stool.
Symptoms may include fewer than three bowel movements a week, hard and dry stools, excessive straining, difficulty passing stool, and a feeling of incomplete emptying afterward. Some patients also experience abdominal bloating, fullness, or discomfort.
Normal bowel patterns differ from person to person. Some people pass stool every day, while others do so less often. Having fewer than three bowel movements a week can be an important sign, but it is not enough on its own to diagnose constipation. A patient who passes stool daily may still be constipated if stools are consistently hard, straining is substantial, or the bowel feels incompletely emptied.
Keeping track of bowel habits can help patients receiving dialysis recognize constipation early and support an assessment of possible causes. A clear change in someone who previously had a regular bowel pattern deserves attention.
Before a medical appointment, it may help to keep a record for a few days of bowel movement frequency, stool hardness, any straining or pain, and when symptoms began. Information about current medications, dietary changes, and recently started supplements may also help identify contributing factors.
The physician will review the symptoms, medical history, and medication regimen and may arrange a physical examination, laboratory tests, or further investigations when appropriate. This approach is also described in the NIDDK’s information on diagnosing constipation.
Important: Seek prompt medical assessment if constipation is accompanied by blood in the stool, persistent or severe abdominal pain, vomiting, an inability to pass gas, or unexplained weight loss. Dialysis patients should also tell their healthcare team about constipation that lasts or becomes progressively worse.
Adjusting Diet and Daily Habits
When managing constipation in dialysis patients, the choice of fiber-rich foods should take account of potassium levels and the individual’s prescribed fluid restriction.
Including Fiber in an Individual Nutrition Plan
An adequate fiber intake is important for preventing constipation and supporting bowel function in dialysis patients. Dietary fiber affects the bulk and consistency of stool and can help promote a more regular bowel pattern. Increasing fiber intake during dialysis care, however, requires attention to dietary considerations that may not apply to people without kidney disease.
Fruit, vegetables, whole grains, and legumes are important sources of fiber. Some of these foods also contain substantial amounts of potassium or phosphorus. Food choices, portion sizes, preparation methods, and frequency of consumption should be considered together, particularly when blood potassium levels are high. The goal is to support an adequate, balanced diet using options suited to the patient’s laboratory results, rather than eliminating fiber-rich foods altogether.
Choosing fruit and vegetables that fit the patient’s blood potassium level can help provide fiber while avoiding unnecessary dietary restrictions. However, patients should not consume dried fruit, high-fiber foods, or fiber supplements without appropriate guidance simply to relieve constipation. Some fiber supplements require an adequate amount of fluid, so patients with a fluid restriction should not use them without medical advice.
Planning fiber intake also requires consideration of appetite, nutritional status, the daily fluid allowance, and other medical conditions, as well as potassium and phosphorus levels. The treating physician and a dietitian experienced in kidney disease should tailor the nutrition plan to the patient’s needs.
For more information about suitable fruit and vegetable choices, portion control, and potassium considerations, see our article, 7 Golden Rules for Fruit and Vegetable Consumption in Dialysis Patients.
Considering Fluid Intake and Daily Activity Together
Fluid intake and daily physical activity should be considered together when helping dialysis patients prevent constipation and maintain regular bowel function. Patients whose fluid intake is restricted because of kidney failure should not increase their water consumption without guidance in an attempt to relieve constipation.
A daily fluid allowance is determined by factors such as remaining urine output, weight gain between dialysis sessions, blood pressure, heart health, and the patient’s overall clinical condition. Fluid tracking should include tea, coffee, milk, soup, and foods that are liquid at room temperature, as well as drinking water. Water contained in some fruit and vegetables may also contribute to total fluid intake.
Inadequate fluid intake may contribute to harder stools and worsening constipation in some patients. Excess intake, however, can cause fluid to accumulate between dialysis sessions, leading to swelling, blood pressure changes, and additional strain on the heart. The healthcare team should therefore review the existing fluid plan, dietary habits, and other possible causes of constipation before considering any change in fluid intake.
The NIDDK’s guidance on eating and nutrition during hemodialysis provides further information about tailoring fluid intake and diet to individual needs. For more on daily fluid monitoring, see our article, 7 Important Rules for Water Intake in Dialysis Patients.
Regular physical activity may help support bowel function and ease constipation. Short walks, gentle movements suited to the patient’s abilities, and avoiding prolonged inactivity may be helpful. An exercise plan should account for age, muscle strength, balance, cardiovascular health, and fatigue that may occur after treatment.
Patients who experience marked weakness, dizziness, or low blood pressure after dialysis should not push themselves to exercise. The duration and intensity of daily activity should reflect their health and their physician’s recommendations. Our article, Exercise During Dialysis Treatment, provides further information about suitable activities.
A regular toilet routine is another useful daily habit. Allowing enough time to use the toilet after breakfast or other main meals may help patients take advantage of the bowel’s natural increase in activity after eating. Responding to the urge to pass stool, avoiding excessive straining, and creating a comfortable setting may also support bowel regularity.
Managing constipation during dialysis requires attention to the patient’s individual fluid plan, suitable physical activity, and regular toilet habits alongside dietary choices. These changes should follow advice from the physician and dialysis team. Persistent symptoms warrant an investigation of possible underlying causes.
Assessing Constipation Medicines for Dialysis Patients
Choosing a constipation medicine requires particular care when kidney function is severely reduced. Some laxatives commonly used by people without kidney disease may cause mineral accumulation, fluid and electrolyte imbalances, or other adverse effects in dialysis patients. Each product therefore needs to be assessed for suitability.
The initial review considers dietary habits, fluid restrictions, physical activity, and other medications. If these measures are insufficient, a physician may prescribe an appropriate laxative. The choice depends on how long constipation has lasted, its severity, stool consistency, coexisting conditions, and the type of dialysis being used.
Osmotic Laxatives
Osmotic laxatives help retain water within the bowel, softening stool and making it easier to pass. They are among the medication groups that may be considered for managing constipation in chronic kidney disease.
Lactulose and polyethylene glycol 3350 without electrolytes, also known as PEG 3350, are options that may be used in dialysis patients when a physician considers them appropriate. Their mechanisms of action, instructions for use, and potential side effects differ.
Lactulose may cause gas, bloating, or abdominal cramps in some patients. Polyethylene glycol products are available in different formulations. Constipation preparations without electrolytes should be distinguished from bowel-cleansing products, which may contain electrolytes and require a large volume of fluid.
Using an osmotic laxative does not mean a patient should change their fluid restriction independently. Any fluid used to prepare or take the medicine should also be considered within the individual’s treatment plan.
Stimulant Laxatives
Stimulant laxatives increase movement in the colon to help stool move through the bowel and be passed.
Sennosides, which are derived from senna, and bisacodyl are active ingredients that a physician may consider for some dialysis patients. They may be options when other approaches have not provided adequate relief.
Stimulant laxatives can cause abdominal cramps, diarrhea, and more frequent bowel movements. Severe or prolonged diarrhea is particularly relevant in dialysis care because it may disturb fluid and electrolyte balance.
A physician should determine how often these medicines are taken and for how long, according to the patient’s needs. Increasing the dose or combining different laxatives without medical guidance to obtain faster results is unsafe.
Stool Softeners and Rectal Treatments
Stool softeners may also be considered for constipation in dialysis patients. Ingredients such as docusate are intended to make stool easier to pass. Their effect may be limited, however, and the expected benefit may not always be achieved, particularly in patients with fluid restrictions.
In some circumstances, a physician may consider rectal treatments such as glycerin or bisacodyl suppositories. These products are not required for every episode of constipation and may not be suitable for continuous use.
Phosphate-containing enemas require particular caution because they can cause serious mineral imbalances in dialysis patients and should not be used without medical advice. If prolonged constipation raises concern about fecal impaction or bowel obstruction, medical assessment should come before trying a laxative or enema.
Constipation Products That Require Particular Caution
The kidneys’ reduced ability to remove certain minerals is an important consideration when assessing laxative safety.
Magnesium-containing laxatives can cause magnesium to accumulate in people with kidney failure. Excessively high blood magnesium levels may cause muscle weakness, low blood pressure, and, in severe cases, heart rhythm problems.
Oral laxatives containing sodium phosphate and phosphate enemas may also be unsuitable for dialysis patients because they can cause phosphorus accumulation and disturb mineral balance.
Some bulk-forming fiber supplements also require caution. Psyllium products, for example, may require a certain amount of fluid for safe use. Their suitability needs individual assessment when a patient has a fluid restriction. Taking them with insufficient fluid can increase the risk of fecal impaction and bowel obstruction.
A product’s availability without a prescription or its herbal ingredients do not establish that it is safe for a dialysis patient.
Precautions When Taking Constipation Medicines
When a dialysis patient needs a constipation medicine, treatment should be assessed alongside their overall health and existing medication regimen. Potential interactions with phosphate binders, iron preparations, potassium binders, and other regular medicines deserve particular attention.
If constipation persists or fails to improve despite treatment, the underlying causes should be reassessed rather than simply increasing the amount of medication.
Severe or persistent abdominal pain, vomiting, pronounced abdominal swelling, an inability to pass gas, or blood in the stool may indicate a more serious health problem. These symptoms require prompt medical assessment.
Treatment aims to support comfortable, regular bowel function while protecting the patient’s fluid and mineral balance and overall health. Constipation medicines, herbal products, and dietary supplements should therefore be used only with the treating physician’s knowledge.
Medicines a Physician May Consider
BC Renal’s guidance includes lactulose and polyethylene glycol 3350 without electrolytes among the options that may be considered. A stimulant laxative may be added in some circumstances. This does not establish that any one product is suitable for every dialysis patient.
Caution With Magnesium and Phosphate Products
Some magnesium-containing laxatives and phosphate-containing bowel-cleansing products can cause minerals to accumulate in kidney failure. Patients should not use phosphate enemas on their own. Rectal administration does not remove the need to assess a product’s suitability in kidney disease.
Precautions With Herbal Products
Dialysis patients may consider herbal teas, natural laxatives, or herbal supplements to relieve constipation. A product’s natural or plant-based origin does not establish its safety in dialysis care. Some herbal products can strongly stimulate the bowel, interact with prescribed medicines, or adversely affect fluid and electrolyte balance.
When kidney function is severely reduced, the body may have difficulty clearing certain substances. Some herbal supplements also contain minerals such as potassium and phosphorus. The ingredients, amount consumed, and duration of use therefore matter.
Particular caution is needed with products sold online that provide incomplete ingredient information or promise rapid bowel cleansing. Some supplements may contain undeclared ingredients, variable amounts of active substances, or unwanted contaminants. Safety cannot be assessed from the name of the plant alone.
Understanding the Difference Between Senna Medicines and Senna Tea
Senna is a plant used to treat constipation because it stimulates bowel activity. Its active compounds, called sennosides, stimulate movement in the colon and help stool pass through. Senna-derived ingredients are therefore found in some constipation medicines.
A licensed senna medicine and herbal tea made from senna leaves should be assessed differently. Medicines have defined amounts of active ingredients and specified instructions for use. In homemade herbal teas, the amount of active substance consumed can vary with the plant material, the quantity used, and the preparation method.
As a result, the effects and possible side effects of senna tea may be difficult to predict. A medicine with a defined amount of active ingredient still carries risks, however. Both types of product need to be assessed in relation to the dialysis patient’s health.
Possible side effects of senna products include abdominal pain, intestinal cramps, and diarrhea. Diarrhea caused by excessive or prolonged use can lead to fluid loss and changes in potassium levels. In dialysis patients, these changes may affect blood pressure, heart rhythm, and general health.
Senna can also interact with certain heart medicines, diuretics, and other treatments. Patients experiencing constipation should therefore consult their physician before using senna medicines or senna tea.
Further information about senna’s effects, side effects, and medicine interactions is available in the NHS patient information on senna.
The decision should be based on the type of product, its ingredients and dose, and the patient’s individual risks. Senna should neither be regarded as automatically unsuitable for every dialysis patient nor assumed to be safe in all circumstances.
Aloe Vera and Herbal Mixtures With Unclear Ingredients
Aloe vera is used in a range of health products, and some oral preparations are marketed for constipation. Products made from different parts of the plant do not have the same effects or safety profile.
Taking aloe latex by mouth can cause abdominal cramps, diarrhea, and disturbances in fluid and electrolyte balance. This material comes from the outer part of the aloe leaf and contains compounds with a laxative effect. Serious adverse effects have also been reported with some aloe preparations.
The National Kidney Foundation identifies oral aloe vera among herbal products that may carry significant safety risks for people with kidney disease. This warning is particularly relevant to people with advanced kidney failure and those receiving dialysis. The risks of oral aloe preparations, however, should be distinguished from those of aloe gels applied to the skin.
Herbal teas and supplements containing multiple ingredients and sold for constipation relief or bowel cleansing also require caution. Products marketed as detox teas, bowel-cleansing regimens, or natural laxatives may contain several different plant substances.
The combined effects of these ingredients may not have been adequately studied in dialysis patients. Some herbal mixtures may also have diuretic or bowel-stimulating effects. These effects do not mean that harmful substances are being safely removed from the body in kidney failure, and the products cannot replace dialysis treatment.
Patients should tell their physician or pharmacist in advance about any herbal tea, supplement, or natural product they are considering for constipation. Where possible, they should show the product packaging and ingredient label to the healthcare professional. Potential interactions need particular attention in patients taking regular medication.
Decisions about herbal products should be based on their ingredients and possible side effects alongside the patient’s medicines, laboratory results, and treatment needs. A natural label or another person’s positive experience is not a sufficient basis for choosing a product.
Symptoms That Require Medical Assessment
Constipation in dialysis patients is often associated with diet, fluid restrictions, inactivity, or medication use. In some cases, however, it may be a sign of a more serious digestive problem. Symptoms that persist, become progressively worse, or differ markedly from the patient’s usual bowel pattern therefore deserve attention.
Constipation accompanied by severe or persistent abdominal pain, repeated vomiting, an inability to pass gas, pronounced abdominal swelling, or a sudden deterioration in general health requires urgent medical assessment. The combination of abdominal swelling, vomiting, and inability to pass gas may indicate a serious condition such as bowel obstruction. Seek emergency medical care rather than waiting at home while trying a new laxative, enema, or herbal product.
Blood in the stool, rectal bleeding, black and tarry stools, or fever accompanying constipation also require assessment without delay. Blood in the stool should not simply be attributed to hemorrhoids or straining. Bleeding can be associated with other digestive conditions.
Medical assessment is also needed for new constipation that continues, a marked change in bowel habits, unexplained weight loss, loss of appetite, or symptoms that fail to improve with appropriate treatment. These findings do not always indicate a serious illness, but they are important reasons to investigate the underlying cause.
Assessment should also take account of conditions that coexist with kidney failure, current medicines, and fluid and electrolyte balance. If abdominal pain and pronounced bloating develop after prolonged constipation, a physician may need to consider fecal impaction or bowel obstruction.
Before the appointment, it may help to note when the last bowel movement occurred, stool consistency, how long constipation has lasted, any abdominal pain or bleeding, and recently started medicines. The healthcare team should also be told about laxatives, herbal products, and other approaches already tried.
After reviewing the symptoms and medical history, the physician will decide whether a physical examination, laboratory tests, or imaging is appropriate. The same investigations are not necessary for every case. Further information about warning symptoms is available in the NIDDK’s information on the symptoms and causes of constipation.
Assessment of constipation in dialysis patients should consider symptom duration, accompanying symptoms, and overall health as well as bowel movement frequency. Patients with urgent symptoms should seek medical care without waiting for their next dialysis session. Other persistent constipation symptoms should be discussed with the treating physician and dialysis team.
Frequently Asked Questions About Constipation in Dialysis Patients
Do I Need to Have a Bowel Movement Every Day
No. Bowel habits vary, and a healthy pattern does not necessarily involve passing stool every day. Assessment considers stool hardness, difficulty passing stool, and a feeling of incomplete emptying alongside frequency.
A noticeable change from a dialysis patient’s previous bowel pattern is particularly relevant. Someone who passes stool daily may still be constipated if stools are hard and substantial straining is needed. Patients receiving peritoneal dialysis may have more regular bowel movement targets to help maintain catheter function.
Can I Increase My Fluid Intake to Relieve Constipation
Dialysis patients should not increase their daily fluid intake on their own because of constipation. Excess fluid can cause swelling, high blood pressure, and additional strain on the heart, particularly in patients with reduced urine output or a prescribed fluid restriction.
The existing diet, fiber intake, medication regimen, and daily activity should be reviewed before changing the fluid allowance. A physician should determine the daily fluid amount based on remaining kidney function and the patient’s clinical condition.
Are Dried Apricots or Prunes Suitable for Everyone
Dried apricots and prunes are often mentioned in dietary advice for constipation because they contain fiber. Drying removes water, however, so potassium may be more concentrated than in the same weight of fresh fruit.
Dialysis patients, particularly those with high blood potassium, should not consume dried fruit without appropriate guidance. The type of fruit, portion size, and frequency should be assessed individually. Including suitable fiber sources chosen by a dietitian is a safer approach than eating large amounts of dried fruit to relieve constipation.
Can Constipation Medicines Be Taken for a Long Time
Constipation may become chronic in some dialysis patients, making regular medication necessary under medical supervision. The suitability and safety of long-term use vary between laxatives.
The active ingredient should be assessed alongside fluid and electrolyte balance and other medicines. If ongoing treatment is needed, a physician should determine the medicine, frequency of use, and monitoring plan.
Severe abdominal cramps, persistent diarrhea, or new symptoms during treatment should be reported to the healthcare team. Patients should not change doses or combine multiple laxatives on their own to increase the effect.
Why Is Constipation Particularly Important in Peritoneal Dialysis
Constipation can affect the function of a peritoneal dialysis catheter as well as bowel regularity. Stool buildup may affect the catheter’s position within the abdomen or interfere with dialysis fluid flowing into or out of it.
Maintaining a regular bowel pattern is therefore an important part of peritoneal dialysis care. Patients should tell their peritoneal dialysis team about a marked change in bowel habits, difficulty draining dialysis fluid, or catheter-related problems.
Abdominal pain, fever, or cloudy drained dialysis fluid requires prompt medical assessment for serious complications such as peritonitis.
The relationship between constipation and catheter function is described in detail in BC Renal’s Peritoneal Dialysis Care Resource. Constipation management should be planned by the patient’s own peritoneal dialysis team. Advice intended for hemodialysis patients should not be applied directly without that assessment.
General Health Information Notice
This content is intended for general health information only and does not replace a medical consultation, diagnosis, or treatment. Assessment of constipation in dialysis patients should consider clinical status, laboratory results, other medical conditions, and the type of dialysis being used. Decisions about laxatives, herbal products, dietary supplements, diet, and daily fluid intake should be tailored by the treating physician and, when needed, a dietitian experienced in kidney disease.
Last updated: October 22, 2026
For comments or corrections concerning this content, please use the contact details for Göl Dialysis Center.
Sources accessed: October 22, 2026
