How Long Does An IBS Flare Up Last?

For people with irritable bowel syndrome, there’s almost nothing more dreaded than an IBS flare-up. IBS is a long-term condition, but those with IBS don’t constantly experience the symptoms; instead, they suffer occasional painful flares that come with a range of gastrointestinal side effects.

This guide will help you understand how long an IBS flare-up will last and what can be done to help. 

Have you considered clinical trials for Irritable bowel syndrome (IBS)?

We make it easy for you to participate in a clinical trial for Irritable bowel syndrome (IBS), and get access to the latest treatments not yet widely available - and be a part of finding a cure.

What is an IBS flare-up? What does it feel like?

Irritable bowel syndrome (IBS) is a long-term condition that affects the gastrointestinal tract. IBS occurs in around 10-15% of the population and is more likely to affect women than men.¹ ²

An IBS flare-up refers to the appearance or sudden increase in severity of IBS symptoms. While IBS is a chronic condition, people with the disorder will suffer symptoms that come and go. Common symptoms that can occur with an IBS flare include:

  • Constipation 

  • Diarrhea 

  • Bloating

  • Gas

  • Abdominal pain 

  • Cramping 

  • Fatigue

  • The feeling of an unfinished bowel movement³

The symptoms of an IBS flare-up depend on the type of IBS that you have. There are three main types of IBS:


Also known as constipation-predominant IBS, patients with IBS-C are likely to experience constipation, gas, bloating, and abdominal pain, and will often need to strain during bowel movements when they have a flare-up. 


Diarrhea-predominant IBS, or IBS-D, causes patients to experience loose or watery stools. Flare-ups for patients with IBS-D are likely to involve diarrhea, abdominal pain, a frequent urge to go to the bathroom, and excessive gas. 


Mixed IBS (IBS-M), is a type of IBS that involves both hard and loose stools. Because of this, IBS-M flares involve symptoms similar to those for both IBS-C and IBS-D. IBS-M patients often variously experience constipation and diarrhea, as well as abdominal pain and gas, during flares.⁴

What can cause a flare-up?

It isn’t known exactly what causes IBS, but there are some identified triggers that can prompt IBS symptoms and contribute to an IBS flare.

Triggers that can cause an IBS flare-up include:

Food and drink

Certain foods and drinks, such as high-FODMAP foods, have been shown to trigger IBS symptoms.⁵


It may not be an obvious trigger, but stress can play a big role in gastrointestinal health due to the strong neuronal connection between the brain and the gut. Stress and exposure to stressful environments have been found to exacerbate IBS flare symptoms.⁶


Smoking has been shown to exacerbate the symptoms of irritable bowel syndrome, due to the nicotine found in cigarettes causing an overproduction of stomach acid.⁷

Abnormal muscle contractions in the intestine

If the muscles in your intestine contract at an unusual rate, they can cause an IBS flare. Weak contractions can slow down food movement and lead to constipation. On the other hand, if the contractions are too fast, they can lead to gas build-up, bloating, and diarrhea.⁸

Gut flora disruption

Our gut contains many microbes that help keep the gut functioning and protect it from dangerous bacteria. Disruptions to the gut flora, such as too little ‘good’ bacteria or too much ‘bad’ bacteria, can therefore contribute to an IBS flare.⁹


An infection in the gastrointestinal system can lead to the development of a type of IBS called post-infectious IBS.¹⁰


Diverticulitis is a condition that damages the pouches of the lower part of the large intestine. The inflammation and infection from diverticulitis can lead to the development of a type of IBS known as post-diverticulitis IBS.¹¹

How long does an IBS flare-up usually last?

The period an IBS flare lasts will vary from person to person, and even within the same person, and can change over time. Typically, you can expect the symptoms of an IBS flare to last for a few days, but this will not necessarily be the same every time. Also, while you may experience a short IBS flare-up at one point, this is no guarantee of what will happen next time. IBS triggers and treatments can also have an impact on how long your flare lasts.

While IBS flares can vary in length, the symptoms that come with flares can vary too. One month you might experience more gas and abdominal pain, while another month you may struggle more with diarrhea.¹²

How can you ease the symptoms of a flare-up?

If you’re suffering from an IBS flare-up, medication and supplements may help ease your symptoms.

Medications that might be prescribed to ease the symptoms of an IBS flare-up include:


Some patients with IBS diarrhea can experience an overgrowth of GI bacteria and so may be prescribed antibiotics to help keep that growth in check.

Anticholinergic medications

Gastrointestinal spasms that often occur during an IBS flare can lead to cramps and abdominal pain. Anticholinergic medications can help to ease these painful spasms. 


Due to the connection between the gut and the brain, there is a strong association between depression and IBS. Because of this, antidepressants can be prescribed to IBS patients to improve mental health and, in turn, reduce typical IBS flare symptoms, such as pain and constipation.

Anti-diarrhea medication

If diarrhea during an IBS flare won’t ease, then you might be prescribed antidiarrheals.


Constipation is another symptom of IBS flare, and you might be prescribed laxatives to help make your bowel movements easier.

Pain medication

Abdominal pain is a common symptom with IBS flares, and people will often need medication to help ease their pain. Therefore, you may be given pain medication as part of your IBS treatment regime.

Other supplements and techniques that can help to ease the symptoms of an IBS flare include:

Peppermint oil

Peppermint oil has been found to help reduce the intensity of IBS symptoms such as pain. Safe for use, if you want to add peppermint oil to your routine, simply place a few drops on your tongue or take peppermint gels/capsules or peppermint-infused tea. Just be careful not to take essential peppermint oils, as pure essential oils can be toxic and dangerous.¹³ ¹⁴


Probiotics can help encourage healthy gut bacteria levels and normalize bowel movements which, in turn, may ease some of the symptoms of an IBS flare.¹⁵

Heat pack

Some patients find that applying a heat pack to the abdomen can help to ease IBS symptoms such as pain and cramping.

Can flare-ups be prevented?

You can’t stop yourself from getting IBS, but you can limit the triggers in your life that contribute to IBS flare-ups. Stress, food, and other external triggers can have a significant impact on your IBS symptoms, and limiting these may prevent flare-up intensity and prevalence. 


The following foods have been shown to contribute to IBS symptom severity. Reducing or ceasing your intake of these foods could help you to limit and calm IBS flares:

  • High FODMAP vegetables: e.g., mushrooms, garlic, onion, asparagus, cauliflower, green peas

  • High FODMAP fruits: e.g., apples, peaches, dried fruit, watermelon, mango

  • Dairy: e.g., cow’s milk products

  • Gluten: e.g., wheat, rye, barley 

  • Legumes and beans 

  • Alcohol 

  • Caffeine¹⁶


Lifestyle habits can have a significant impact on IBS flare-ups. Making these changes to your routine could help you prevent or reduce IBS symptoms:

Reducing stress: Stress can be hard to avoid, but it’s important to try and minimize stress in your life if you have IBS, as stress has been linked to an increase in IBS symptoms. Relaxation techniques such as meditation, yoga, or breathing exercises can help you manage stress.¹⁷

Regular exercise: Exercise may be able to help prevent the onset of IBS flares, with research showing that exercise can decrease the severity of IBS symptoms.¹⁸

GI therapy: We know that there is a connection between the gut and the brain, and therapy has been found to significantly reduce the symptoms of IBS in the long term. Therapists trained in gastrointestinal psychology, in particular, could help you calm your IBS flare-ups.¹⁹

Quitting smoking: Smoking is never a good idea, but it’s especially important to try to quit smoking if you have IBS. Research shows that smoking can make IBS symptoms worse, so reducing or eliminating exposure can assist in preventing IBS flares.⁷

When to see a doctor

If you have IBS, you should see a doctor if you experience any new symptoms or if there is a sudden spike in your symptoms’ severity. This could be a sign of something new, or it could mean your treatment regime needs to be adjusted. Certain side effects that should prompt a visit to your doctor include:

  • Blood or mucus in your stool 

  • Excessive diarrhea or constipation, especially if out of the ordinary

  • Foul-smelling or painful gas 

  • Nighttime symptoms that wake you up

  • Severe and debilitating cramps 

  • Severe and persistent abdominal pain²⁰

The lowdown

IBS flare-ups can be painful, embarrassing, and debilitating. Unfortunately, there is no cure for IBS, but with the help of medicine, food management, and stress-reducing tools, it is possible to reduce IBS frequency and severity.

  1. The epidemiology of irritable bowel syndrome (2014)

  2. Statistics | International Foundation for Functional Gastrointestinal Disorders

  3. Symptoms and causes of irritable bowel syndrome | National Institute of Diabetes and Digestive Kidney Disease

  4. Definition & facts for irritable bowel | National Institute of Diabetes and Digestive and Kidney Diseases

  5. Try a FODMAPs diet to manage irritable bowel syndrome | Harvard Health Publishing

  6. Irritable bowel syndrome: 7 trigger busters | Cleveland Clinic

  7. Association of cigarette smoking with irritable bowel syndrome: A cross-sectional study (2020)

  8. Effectiveness of probiotics in irritable bowel syndrome: Updated systemic review with meta-analysis (2015)

  9. Characteristics and risk factors of post-infection irritable bowel syndrome after campylobacter enteritis (2021)

  10. Irritable bowel syndrome: Symptoms and causes | Mayo Clinic

  11. Irritable bowel syndrome: Overview (2019)

  12. Irritable bowel syndrome: Diagnosis and treatment | Mayo Clinic

  13. The impact of peppermint oil on the irritable bowel syndrome: a meta-analysis of the pooled clinical data (2019)

  14. Peppermint oil | National Center for Complementary and Integrative Health

  15. Effectiveness of probiotics in irritable bowel syndrome: Updated systemic review with meta-analysis (2015)

  16. High and low FODMAP foods | Monash University

  17. Impact of psychological stress on irritable bowel syndrome (2014)

  18. Physical activity improves symptoms in irritable bowel syndrome: a randomized controlled trial (2011)

  19. Cognitive-behavioral therapy for patients with irritable bowel syndrome: current insights (2017)

  20. Changes you should not ignore if you have IBS | International Foundation for Functional Gastrointestinal Disorders

Have you considered clinical trials for Irritable bowel syndrome (IBS)?

We make it easy for you to participate in a clinical trial for Irritable bowel syndrome (IBS), and get access to the latest treatments not yet widely available - and be a part of finding a cure.

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