Abdominal pain and cramps: where the pain comes from
Cramp, fullness or stabbing: why the gut signals pain, when it is harmless and when it needs checking.
How solid is the research? Trust score 3 of 5:Promising
Well supported are the positive diagnosis of IBS without unnecessary tests, the handling of warning signs, and the effect of antispasmodics and peppermint oil – for the latter, however, with weak quality of evidence. That pain arises because the gut reacts more sensitively to stretching is understood in outline; many details are still open.
Cause or consequence? Root cause 2 of 5:Rather a consequence
Abdominal pain is usually a consequence, not a root cause: it arises from SIBO, a sensitive stomach, intolerances, gallstones, IBS or the pelvic floor. But chronic pain can take on a life of its own, because the nervous system becomes ever more sensitive through central sensitisation. Hence a middle rating.
Healthy state
The gut wall has only a few sensors for cutting or burning, but many for stretching. A healthy gut therefore rarely makes itself felt: food, gas and stool pass by without us noticing anything.
When the wall stretches, for example from gas, gut contents or stool, these stretch sensors fire. Above a certain intensity they pass a signal via the spinal cord to the brain, and that becomes pain.
The muscles of the gut work in waves. At the end, sphincters and the pelvic floor make sure everything takes its path without strong straining.
The gut has a nervous system of its own, with many millions of nerve cells, and is connected to the brain through the Vagus nerve The tenth cranial nerve and the most important nerve of the rest-and-digest system. It connects the brainstem and the abdominal organs; most of its fibres tell the brain what is happening in the gut. More in the chapter “The vagus nerve: the data line between belly and head” and the spinal nerves. The brain filters out a large part of the signals, which is why everyday life is mostly symptom-free.
Disrupted state: causes and effects
With visceral hypersensitivity, the nerves signal pain at a degree of stretching that would otherwise at most feel like pressure. Measurements with a balloon in the rectum show: in Irritable bowel syndrome Recurring abdominal pain linked to bowel movements, without tests finding another cause. Today it is understood as a disorder of gut–brain interaction. More in the chapter “The gut-brain axis” the pain threshold is lower than in healthy people. It is not the stimulus that is greater, but the threshold that is smaller.
Gas and stretching are closely linked with IBS and a sensitive stomach. In a large survey, 65% of people with IBS and 51% with functional dyspepsia reported bloating or visible distension, compared with 14% without these conditions. What often matters is not the amount of gas, but how sensitively the gut reacts to it.
Cramps arise when the smooth muscle of the gut wall contracts strongly and irregularly. Such pain comes in waves, eases in between and returns. This is exactly where antispasmodics act: they relax the muscle.
If the pain lasts longer, the nervous system itself becomes more sensitive, which experts call central sensitisation. Stress, lack of sleep and anxiety lower the threshold further. That is why the same belly hurts more on a tense day than on a calm one.
Not every abdominal pain comes from the gut. Biliary colic sits under the right ribcage and often comes after fatty food, a kidney stone causes wave-like flank pain. Period pain and endometriosis, the bladder or tense muscles can also show up as abdominal pain. The widespread idea that abdominal cramps come from Candida is not supported by studies.
Where it comes from and where it leads
The same symptoms can have different roots. This map shows what may be involved in this problem and what may follow from it.
Possible causes. Crohn’s & colitis, SIBO, Sensitive stomach, Bile & liver, Intolerance, Constipation, Hormones & cycle, Gut-brain axis, IBS after infection, Mast cells, Diverticula & haemorrhoids, Gut immunity, Antibiotics, Vagus nerve, Acid blockers (PPI), Bile acids, Medication, Gastroparesis, Ileocaecal valve, Weak cleaning wave, Long Covid, POTS & connective tissue, Low enzymes, Leaky barrier, Parasites, Supplements, Pelvic floor, Methane & H₂S, Autoimmunity, Stress & sleep, Mould, Low variety, First microbiome, Heartburn, No gallbladder, Low butyrate, Thin mucus layer. Possible consequences. Food fear, Nutrient deficiency, Brain fog & fatigue
- Possible causes
- This problem
- Possible consequences
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Move the mouse over a box: its connections are highlighted and everything else steps back.
Tap a box to highlight its connections. Tap it again to open the chapter.
Connections, not certainty: a link means “can”, not “must”. What applies to you is best clarified in a talk with your doctor.
What often helps
Lifestyle
Diet, exercise, sleep, social contact and dealing with stress.
- Warmth on the belly A hot-water bottle, a heat pack or a warming patch relaxes the muscle and can ease the pain. Superficial warmth has mainly been studied for period pain, where it performed about as well as painkillers in individual studies. Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [1]
- Eat calmly and at regular times Several smaller meals instead of a few large ones, chew slowly, do not eat right before bed. This is practical experience and not tested in large studies, but it often helps with fullness and cramps. Plausible How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
- Stay active Regular, moderate exercise improved IBS symptoms in a meta-analysis of 10 studies with 437 people. There is no single recommended programme; walking, cycling or swimming are enough. Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [2]
- Soften the stool when pain comes from constipation When hard stool stretches the gut, more fluid and soluble fibre such as psyllium husk help first. The constipation guideline recommends them; increase slowly and drink enough with them. Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [3]
- Turn stress down Stress increases how strongly pain is felt in the belly. Breathing and relaxation exercises, breaks and good sleep are no substitute for treatment, but they raise the pain threshold again. With persistent symptoms, gut-directed methods often help further. Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [4]
Natural supplements
Supplements do not replace a medical check-up. Discuss dosage and interactions with your doctor or pharmacist.
- Peppermint oil capsules In a meta-analysis of 10 studies with 1030 people, peppermint oil improved abdominal pain more often than placebo (NNT 7). The quality of evidence is very low, and side effects such as heartburn occurred more often. Take enteric-coated capsules, and be careful with reflux. Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [5]
- Peppermint and caraway oil The fixed combination Menthacarin improved abdominal pain and fullness in an analysis of 5 studies with 580 people. The studies are small and partly funded by the manufacturer. Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [6][7]
- Iberogast (STW 5) A mixture of six plants, including caraway, fennel and anise, improved symptoms in individual studies. The studies are manufacturer-funded. The classic formula contains greater celandine, which in rare cases damages the liver; a celandine-free version (STW 5-II) also exists. In reviews, peppermint oil is the only herbal treatment for IBS named consistently. Plausible How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [8][9]
Medical treatments
Information, not a treatment recommendation. Decide together with a doctor. Approval and availability differ from country to country.
- Have IBS diagnosed properly IBS is a positive diagnosis: if the pain is related to bowel movements, stool frequency or stool form, has lasted for months and there are no warning signs, no elaborate process of ruling out other conditions is needed. The Rome criteria (since 2026, Rome V) describe exactly this. Established How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [10][11][12]
- Have warning signs checked Blood or black stool, unintended weight loss, fever, pain that wakes you at night, anaemia, newly appearing symptoms from about age 50 or pain outside the abdomen should be checked by a doctor. With sudden, most severe pain, a hard abdomen, fever and no bowel movement or wind, seek medical help at once. Warning signs are common in the general population and must be seen in context, not one by one. Established How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [13][10]
- Antispasmodics Drugs such as mebeverine or otilonium relax the gut muscle and are part of the basic treatment for IBS. The effect is limited, and approval and availability differ from country to country. They are usually prescribed; ask at a practice in your country. Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [14][10]
- When the pain comes with your period With severe period pain, pain during bowel movements or sex, and symptoms that come and go with the cycle, think of endometriosis. Women with endometriosis are diagnosed with IBS about three times as often. A gynaecological assessment is worth having. Promising How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [15][16]
- When nothing is enough: approaches via the gut-brain axis Gut-directed hypnosis, cognitive behavioural therapy and low-dose older antidepressants raise the pain threshold. In a network meta-analysis of 68 studies, tricyclic antidepressants and psychotherapeutic approaches in particular were effective. These drugs and methods belong under medical supervision. Well supported How we rate the evidence Established Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies. Well supported Several randomised studies in humans with largely consistent results. Promising Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies. Plausible Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms. Experimental Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open. [17][18][19]
In the mood for something completely different? Another one, at random
How we rate the evidence
- Trust score 5 of 5:Established
- Recommended in medical guidelines or supported by several consistent meta-analyses of randomised human studies.
- Trust score 4 of 5:Well supported
- Several randomised studies in humans with largely consistent results.
- Trust score 3 of 5:Promising
- Single randomised or controlled studies in humans, not yet independently confirmed — or many consistent observational studies.
- Trust score 2 of 5:Plausible
- Two cases: first observational or pilot studies with small samples — or a settled basis that is not in dispute, such as movement, sleep or meal pauses. But not tested in humans for symptoms.
- Trust score 1 of 5:Experimental
- Barely studied in humans. Mainly lab and animal studies or theoretical reasoning; whether it helps is open.
Sources
- Puhakka et al. 2026: superficial warmth for pain in gynaecology (Frontiers in Medicine)
- Wu et al. 2026: exercise therapy in IBS, meta-analysis (Frontiers in Medicine)
- Chang et al. 2023: Joint AGA/ACG guideline on the pharmacological treatment of chronic constipation
- Heitkemper & Chang 2009: ovarian hormones and gut symptoms in women with IBS (Gender Medicine)
- Ingrosso et al. 2022: peppermint oil in IBS, systematic review and meta-analysis (Alimentary Pharmacology & Therapeutics)
- Madisch et al. 2022: peppermint and caraway oil (Menthacarin) in functional gut complaints, meta-analysis (Digestive Diseases)
- Li et al. 2019: peppermint and caraway oil in functional dyspepsia, meta-analysis (Evidence-Based Complementary and Alternative Medicine)
- Pastras et al. 2026: herbal remedies in IBS and their place in guidelines (Nutrients)
- Andresen et al. 2024: herbal combination STW 5-II in functional dyspepsia, meta-analysis (Digestion)
- Lacy et al. 2021: ACG clinical guideline on irritable bowel syndrome (American Journal of Gastroenterology)
- Mearin et al. 2016: Rome IV criteria for functional bowel disorders (Gastroenterology)
- Goyal et al. 2026: what is new in Rome V? – diagnostic criteria for disorders of gut-brain interaction (Indian Journal of Gastroenterology)
- Sjölund et al. 2026: warning signs in the general population and in disorders of gut-brain interaction (United European Gastroenterology Journal)
- Sacco et al. 2026: overview of abdominal pain in IBS – visceral hypersensitivity, gas and stretching (Journal of Clinical Medicine)
- Chiaffarino et al. 2021: endometriosis and IBS, meta-analysis (Archives of Gynecology and Obstetrics)
- Duong & Ramdass 2026: a shared nerve pathway in endometriosis and IBS (Biomedicines)
- Khasawneh et al. 2026: neuromodulators and behavioural therapies in IBS, network meta-analysis (Gut)
- Black et al. 2020: Psychological therapies for IBS, network meta-analysis of 41 trials (Gut)
- Vasant et al. 2021: British Society of Gastroenterology guideline on irritable bowel syndrome (Gut)
- Groen et al. 2026: thresholds for rectal distension in IBS (United European Gastroenterology Journal)
- van Gils et al. 2026: bloating and distension in IBS and functional dyspepsia (United European Gastroenterology Journal)
- Drossman et al. 2026: disorders of gut-brain interaction and the Rome V process (Gastroenterology 170:1083–1098)
- Krieger et al. 2025: opioids in renal colic, benefit doubtful (BJUI Compass)
- EASL 2016: European guideline on the prevention, diagnosis and treatment of gallstones (Journal of Hepatology)
- ISAPP 2023: The gut mycobiome and misinformation about Candida
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