Bowel problems in Parkinson’s

Bowel problems can include a range of symptoms and causes, including constipation, gastroparesis, diarrhoea, rectal bleeding, unexplained weight loss and other gastrointestinal problems. Bowel issues can occur in anyone, but are more likely in people with Parkinson’s.

The most common bowel issue – affecting up to 65% of people with Parkinson’s – is constipation, which can make it harder or more painful to poo, and cause hard, less frequent bowel movements.

Other bowel problems that can be caused by Parkinson’s include:

• Delayed gastric emptying (gastroparesis)
• Diarrhoea, which may occur as a side effect of certain Parkinson’s medicines
• Overflow diarrhoea as a result of severe constipation and faecal loading of the bowel.

On this page you can find information about all the signs and symptoms of bowel problems in Parkinson’s, how they are diagnosed and treated, and what you can do to provide relief at home.

What is a normal bowel movement?

It is easy to become worried about your bowel activity, but the range of normal can be quite broad, ranging from a few times a day to three or four times a week.

What is important is that passing stools does not cause pain or unnecessary strain. Focus on what is normal and healthy for you, and remember that bowel activity is affected by food, fluid intake and exercise, so will vary according to what you are eating and doing.

Signs and symptoms of bowel problems

The signs and symptoms of bowel problems in Parkinson’s include:

Constipation

Constipation is a common health problem that affects our ability to make normal bowel movements. If you are constipated you may experience:

• infrequent bowel movements
• stools (faeces) that are hard and difficult to pass
• excessive straining when trying to pass stools
• pain when passing stools
• much longer time sitting on the toilet trying to pass stools.

Constipation can have a severe impact on the management of Parkinson’s symptoms due to the reliance on the bowel to absorb levodopa medication. Research suggests constipation is the number one reason why Parkinson’s can suddenly deteriorate due to this poor absorption of levodopa from the intestine.

If symptoms are severe, it may make you feel unwell, nauseous or lethargic. It can also make older people confused and restless. Constipation may also make bladder emptying difficult, or emptying may become so urgent that incontinence results.

Gastroparesis (delayed gastric emptying)

Gastroparesis is a long-term condition meaning food passes through the stomach slower than it should do.

Symptoms of gastroparesis can include:

• feeling full quickly when eating
• abnormal discomfort from bloating
• nausea
• vomiting
• weight loss and malnutrition
• It can also affect how well your Parkinson’s medications work

Diarrhoea

Diarrhoea is defined by the WHO as the passage of three or more loose or liquid stools per day (or more frequent passage than is normal for you).

In general, diarrhoea is often a symptom of an infection in the intestinal tract, or food poisoning. In Parkinson’s, overflow diarrhoea is a common issue when the bowel is severely impacted with faeces. This is where liquified faecal matter leaks around the hard stool, causing the person to pass a loose stool.

One category of Parkinson’s medication called COMT inhibitors can cause diarrhoea as a side effect.

Weak sphincter

You may also experience leakage caused by difficulties in squeezing the sphincter muscles in your bottom.

Your sphincter can become weakened by changes in this area, for example for piles, or childbirth. This can cause difficulties in holding on to stools, resulting in incontinence if you cannot reach a toilet in time.

Problems caused by limited mobility

Parkinson’s often affects movement, and this can make it difficult to wipe after using the toilet, leading to soiled underwear. People with Parkinson’s may also struggle to remove trousers and underwear due to slowness movement and stiffness in their muscles.

How are bowel problems in Parkinson’s diagnosed?

Usually your healthcare professional would take the history of your bowel pattern symptoms, including frequency, consistency, weight loss and other signs and symptoms mentioned above. An abdominal examination is performed by the doctor, and in the case of constipation you may also be referred for an abdominal x-ray to assess for faecal loading.

How common are bowel problems, and are they always linked to Parkinson’s?

Many people experience bowel problems such as constipation or gastroparesis for a variety of different reasons. However, people with Parkinson’s may be more likely to experience problems with their bowels than the general population. This is due to bowel changes related to the condition.

Parkinson’s itself causes the bowel to slow down as the natural wave of movement along the bowel (called peristalsis) is lost or reduced. Parkinson’s and constipation tend to go hand in hand. Some people report an increase in constipation after commencing levodopa medication.

But not everyone with Parkinson’s will have bowel symptoms, and there are many effective ways to manage any problems that arise.

If you are concerned about your bowel movements, or experiencing problems, always speak to a healthcare professional.

What causes bowel problems?

In general, bowel problems can be caused by a number of different reasons, including diet, exercise, illness and medical conditions.

But some problems, especially reduced bowel movement or constipation, are particularly common in Parkinson’s. This is often a result of slowness of movement (bradykinesia) and muscle rigidity, both of which affect the bowel.

Causes of constipation and other bowel issues in Parkinson’s include:

• Slowness of movement and muscle rigidity can affect the bowel muscles, making bowel movements slower and more difficult
• Chewing and swallowing issues can make eating fibre-rich foods like fruit and vegetables – which can aid bowel function – harder. Eating, drinking and exercise encourages waste matter to pass through the large intestine, so infrequent meals with insufficient dietary fibre, and/or a lack of exercise, is often a significant cause of constipation
• Tremor can make it easier to spill drinks, and anxiety around this can cause people with Parkinson’s to reduce their fluid intake. When stools remain unpassed for a long time, they become harder as the body absorbs more water from them. If stools build up in the rectum they can become impacted and block the rectum. They may also overflow as lumps of stool or watery mucus.
• Exercise is important to stimulate the bowel. If Parkinson’s makes activities more difficult, the bowel may be less stimulated and the intestines can become sluggish.
• Constipation can be a side effect of taking anticholinergics, an older type of Parkinson’s medication that is not very often used today. Anticholinergic medication should be avoided in the older person with Parkinson’s due to its side effects such as dry eyes, dry mouth, constipation and confusion. Sometimes they are prescribed for reducing tremor and muscle stiffness, either on their own (in the early stages of Parkinson’s) or alongside drugs like levodopa.
• Parkinson’s itself can impair automatic relaxation of the pelvic floor ,which is necessary to straighten the last part of the intestine and allow the faeces to pass. This happens particularly during ‘off’ periods when medication is not working well
• Constipation may also be caused by hormonal, neurological or anatomical factors, such as impaired muscle relaxation, or it may be a side effect of medication
• Finally, diarrhoea may occur as a side effect of certain Parkinson’s medicines, but this may be overcome by adjustments to the medication regime, so it is important to mention any diarrhoea to your doctor.

Parkinson’s medications and bowel problems

Bowel problems in Parkinson’s can occur due to the condition itself, but also as a result of taking certain medications.

Absorption of levodopa

Levodopa is not absorbed from the stomach, but the stomach plays an important role in controlling how levodopa reaches the parts of the small intestine where it is absorbed.

• Some other Parkinson’s medicines, including dopamine agonists and anticholinergics, can delay gastric emptying (known as gastroparesis), as can severe stomach acidity. However, over-treatment of this problem can also prevent the break-down of levodopa tablets, leading to incomplete absorption.
• Gastric emptying can be delayed by Parkinson’s itself or by constipation caused by the colon-gastric reflex. Levodopa tablets may remain in the stomach for a long time, leading to delayed absorption in the small intestine and a delayed response to the treatment.
• An enzyme called dopa-decarboxylase that is present in the stomach lining can convert levodopa trapped in the stomach into dopamine, making it unavailable to the central nervous system.
• Dopamine formed in the stomach may stimulate gastric dopamine receptors, leading to stomach relaxation and reduced gastric motility. This can worsen the problem.
• It is advisable to drink a full glass of water (200ml) when swallowing the levodopa tablets. This will help flush the levodopa through the stomach and aid it to get to the small intestine, where it is absorbed.

It is sometimes preferable to take levodopa on an empty stomach, but you should always follow your doctor’s instructions. When the timing is clashing with food or meals, the general advice is to either take the levodopa tablet 30-60 minutes before the meal, or 60-90 minutes after the meal.

Liquid levodopa may improve motor fluctuations by ensuring better absorption than standard preparations in the case of sudden OFF periods, especially when taken after meals.

Subcutaneous infusion is a method of administering medication into the fatty tissue just below the skin, bypassing the gastrointestinal tract. This method can be effective in controlling motor fluctuations when administering the dopamine agonist apomorphine.

Treatments for constipation and other bowel problems

The first step in dealing with bowel disorders is to talk to your doctor. They will probably review your medication to see if this is a contributory factor.

Whilst it is usually possible to control any difficulties with diet, fluid intake and exercise, your doctor or Parkinson’s nurse specialist will be able to advise further, and may prescribe laxatives in severe cases of constipation (see below).

Diarrhoea may occur as a side effect of certain Parkinson’s medicines – your doctor can fix this by adjusting your medication. In the case of bowel impaction , an intense course of laxatives may be used to clear the faecal loading.

If you have any concerning features such as unintentional weight loss or rectal bleeding, then you may need to be referred for specialist assessment.

The following healthcare professionals can also advise on aspects of bowel care:

• A dietitian will be able to advise on diet and fluid
• A physiotherapist may be able to help with advice and abdominal exercises which will help in passing stools
• A speech and language therapist can help with swallowing problems. They may be able to advise on ways of relaxing your throat, and give guidance on posture and exercises to help overcome any difficulties you have
• An occupational therapist may be able to suggest practical ways to overcome any difficulties you have with eating and drinking.

Laxatives and constipation

If diet, fluid intake, abdominal massage and exercise do not control constipation, then laxatives may be helpful. They should be used with caution and only under the direction of a doctor, as some may lose effect over time.

There are several types available, including fibre-based laxatives and ‘osmotic’ laxatives which draw water into the bowel and retain it there to soften and bulk up stools to make them easier to pass. One example is Movicol, a solution which delivers water to the large intestine to increase the bulk of the stool. This triggers the muscles of the bowel to contract and produce a bowel movement. The water in Movicol solution is not absorbed into the body, so it can also soften and lubricate the stools to promote comfortable bowel movements. In addition a stimulant laxative (Senna) may be used to help stimulate the bowel to move.

It is crucial that, at first, your doctor checks regularly that the dose of any laxative is right for you. Once this is achieved, you will probably be able to maintain the right balance on a day-to-day basis, taking account of what you do and how you feel from one day to another.

When oral laxatives have not been successful, enemas (a liquid inserted into the rectum through a tube, usually with the aim of triggering bowel movement and the passage of stools) can be very effective in improving severe constipation.

What can I do to prevent or relieve constipation and bowel problems at home?

Remember that learning to manage your bowels will take time and patience, so don’t expect to solve problems overnight. It may take a few weeks to adjust diet and so on, so be patient. There are also plenty of ways you can help yourself.

Diet and fibre

A healthy lifestyle will enhance bowel efficiency and consuming the appropriate amounts of fibre and fluid are key factors.

Fibre often aids digestion, but too much bulk from fibre can increase constipation, so the balance needs to be right. Your doctor should be able to refer you to a dietician for help with this. Any increase in fibre should be gradual to avoid flatulence (wind) or bloating.

Tips for managing constipation at home:

• eating wholegrain cereals and bread
• eating fruits and vegetables – fresh, frozen, raw and cooked. If you have trouble chewing and swallowing, look for soluble varieties and fruit juice drinks. Prunes, kiwi fruit, pears and other dried fruits are particularly good, natural laxatives. Avoid or reduce bananas in your diet, as these tend to have a binding effect.
• avoiding foods with a high fat content, such as fatty meats, butter and cream, and foods that increase stomach acidity
• consuming a balance of protein and carbohydrates. High levels of protein are only problematic when associated with fat. Carbohydrates may be preferred to protein, but large quantities delay gastric emptying
• drinking plenty of fluids, which will help the digestion of fibres. Try to drink approximately 1.5-2 litres per day in total. This can be made up of six to eight cups (8oz/225ml) throughout the day, including water, tea, coffee, milk and juice.
• carbonated drinks may cause bloating and alcohol can act as a diuretic. This can make constipation worse, so try to drink these only in small quantities
• having a warm drink and something to eat as soon as you get up in the morning, as both stimulate bowel activity.

If you find it difficult to increase your fluid and fibre intake because of eating and drinking difficulties, you could try these practical suggestions:

• use insulated cups for warm drinks, if necessary with a lid and spout to avoid spillages. Weighted cups are also useful if you have a tremor
• if large meals are daunting because eating is slow or you have difficulty chewing, try several smaller meals a day instead
• place a rubber mat under your plate to prevent it slipping
• try special cutlery to make eating easier, such as a combined knife/fork; a ‘rocking’ knife that allows cutting one handed. An occupational therapist can advise further.

However, you may find increasing your natural fibre and fluid intake does not relieve your bowel difficulties. If constipation is the problem, then medications such as bulk formers or stool softeners may help. Several products are available, so ask your doctor or a dietician for advice.

Exercise

Physical exercise may help in relieving or preventing bowel problems. Exercise can stimulate the bowel muscles and improve your ability to pass stools. It can also strengthen the pelvic floor muscles, which helps to reduce constipation.

If you find exercise difficult, a physiotherapist can advise further.

Going to the toilet

It is important to try to relax when going to the toilet. Try not to rush, or become too preoccupied with your bowels.

• Try to empty your bowels at the same time of day if you can. This may be after breakfast, a hot drink or when you are ‘on’ and medication is working well
• When you feel the urge, go to the toilet as you soon as you can. Delaying can lead to hard stools, which are more difficult to pass.
• Try resting your feet on a small stool or footrest so you feel more comfortable and position your body into a squat. Look for a footrest that does not slide on the toilet floor and has a non-slip base (e.g. a Squat Easy). This may especially help if your feet do not touch the floor when sitting on the toilet
• If the toilet seat is too low, you may find it difficult to sit down on it and get up again afterwards, especially if you have stiff hips. You may find using grab rails, or a raised toilet seat with adjustable clips to fix it securely to the bowl, can help.
• Do not sit on the toilet for more than about five minutes and don’t strain hard to pass a stool. Listen to your body, leave it for a while and try again later
• If mobility problems make it difficult to wipe after using the toilet, try using wet wipes, a bidet, or an adapted bottom wiper.
• If movement and co-ordination difficulties make it difficult to remove clothing when using the toilet, consider adaptions. For example, adding a tab to your trouser zip, or opting for elasticated waistbands instead of buttons, may help. If you wear skirts, tucking your skirt into the waistband allows you to use both hands for stability, and prevents it from dangling into the toilet bowl.
• Find out if your country has a scheme offering disabled people independent access to locked public toilets in shopping centres, pubs, cafés, bus and train stations and so on. For example, the Radar Key, used in the UK and Ireland, or the Eurokey, used across Europe.

Be proactive in addressing bowel problems

Constipation and other bowel issues can feel embarrassing and worrying. But it is important to initiate a conversation with healthcare professionals in order to best manage your symptoms.

Unfortunately, in the past, failure by healthcare professionals to recognise those most at risk of developing bowel difficulties was a major stumbling block in managing the condition. This, coupled with the patient’s embarrassment in approaching the subject, meant that any problems often went undiagnosed or untreated for some time.

Fortunately, most of those at risk are now identified early, which means preventative measures can be put in place to reduce the risk of complications. A proactive approach to treatment really can reduce the impact that bowel disorders may have.

References and acknowledgements

We would like to thank the following:

• Dr Anton Emmanuel (National Hospital for Neurology & Neurosurgery, Queen Square, London, UK) for his help in reviewing an earlier version of this information.
• Parkinson’s UK for permission to use the following source(s) in compiling this information: bladder and bowel changes in Parkinson’s.
• Brian Magennis, Advanced Nurse Practitioner and Adjunct Lecturer / Assistant Professor UCD, Mater Misericordiae Hospital, Ireland

Content last reviewed: July 2026