Ulcerative Colitis Tenesmus: The Empty Urge

Tenesmus is the feeling that you urgently need to open your bowels when there is little or nothing there to pass. In ulcerative colitis it is generated almost entirely in the rectum, by a lining that has become hypersensitive and a reservoir that has become smaller, so the alarm fires on a smear of mucus instead of on a stool. It is not constipation, it is not the same thing as urgency, and it is not in your head.

It is also, by a wide margin, the most neglected common symptom in ulcerative colitis. A Europe PMC search on 27 September 2026 returned 53 MEDLINE-indexed papers with "tenesmus" in the title, across all of human and veterinary medicine, and exactly one of those mentioned colitis anywhere in its abstract. The same search shape for "urgency" returned 50. Tenesmus appears in neither of the two patient-reported scores that colitis care actually runs on. The largest proctitis trial we could find did not measure it. That absence is the real story of this article, and it explains a lot of the frustration in the threads.

What tenesmus actually is, and why nobody agrees on the definition

Tenesmus is the persistent or recurring sensation of needing to defecate, with little or nothing passed when you do. That is the working definition most gastroenterology writing uses. The word comes from the Greek for straining, which is a clue that the original meaning was about effort rather than about emptiness.

The problem is that different specialties use it for different things, and almost nobody says which they mean.

Palliative medicine defines it as a pain. A 2025 case report in a palliative care journal opens by defining rectal tenesmus as "the painful sensation of incomplete evacuation of the bowels", notes that it is most often caused by rectal carcinoma, and describes a significant neuropathic component to the pain (Murphy 2025). In that world tenesmus is a pain problem, treated with pain drugs.

Gastroenterology uses it for the urge, painful or not. Plenty of people with colitis describe a nagging, pressing, non-painful false alarm and call it tenesmus. Plenty describe a throbbing rectal pain with every attempt and call it the same word.

Rome does not list it as a disorder at all. The Rome criteria are the reference standard for naming gut-brain disorders, and the 2026 anorectal chapter defines faecal incontinence, proctalgia fugax, levator ani syndrome, dyssynergic defecation and rectal hyper- and hyposensitivity. Tenesmus is not one of the named entities (Rao 2026). It is a symptom that turns up inside several of those diagnoses rather than a diagnosis in its own right.

And the word has been quietly repurposed. A 2025 engineering paper describing an instrumented toilet coined "eu-tenesmus" for the ordinary interval between the last stool dropping and starting to clean up, averaging 74.8 seconds in 11 volunteers (Song 2025). It is a perfectly reasonable piece of jargon, and it means the opposite of what you mean when you use the word.

The practical consequence: when you say "tenesmus" to a clinician, say what you actually experience as well. The word is doing less work than you think.

Tenesmus, urgency, constipation and incomplete evacuation are four different things

They overlap and they get used interchangeably, including by clinicians and including in research papers, which is a large part of why the numbers in this field disagree with each other. Here is how they separate.

One of the few studies to count them as separate items is instructive. In 71 people with inflammatory bowel disease (33 Crohn's disease, 38 ulcerative colitis) who completed a structured questionnaire, 52 reported urgency, 32 reported tenesmus, 38 reported incomplete evacuation and 17 reported excessive straining (Petryszyn 2018). Different counts, same cohort, same day. They are not synonyms.

That paper is worth reading carefully rather than quoting, because its own arithmetic does not fully hold together. It reports faecal incontinence in 31 of the 71 patients, which is 44%, but concludes that "faecal incontinence is reported by over 50% of patients". It also reports 33 patients incontinent to liquid stool, which is more than the 31 said to have faecal incontinence at all. We could not reconcile either figure from the abstract, so we have quoted the counts and not the percentages. The paper also reports that everyday functioning was worsened "because of urgency/tenesmus" in 39 patients, as a single combined item, which means it cannot tell you how much of that burden belonged to tenesmus on its own.

Why an inflamed rectum produces a false alarm

Three changes have been measured directly, and none of them is about how much stool is present.

The rectal wall becomes hypersensitive to stretch. In a study using a rectal probe in nine people with active disease limited to the rectum and sigmoid colon, compared with 17 healthy volunteers, the patients were hypersensitive to mechanical distension (Drewes 2006). Nine patients is a very small study and the authors present it as such.

The muscle is held tight, so the reservoir is smaller. In the same experiment the wall's compliance and stiffness were no different from controls, but the hypersensitivity disappeared once the smooth muscle was pharmacologically relaxed. The authors concluded that the smooth muscle in an inflamed rectum is tonically contracted, producing a decreased rectal circumference. They also held a sustained distension at the pain threshold for two minutes and found it did not produce central pain amplification, which led them to conclude that the hyperalgesia is more likely peripheral than central (Drewes 2006). That is a nine-patient finding, and it is the closest thing we found to a direct answer to "is this in my head".

Those authors ended their paper by suggesting that drugs affecting smooth muscle contraction might help in difficult cases. Twenty years later, we could find no trial testing an antispasmodic against tenesmus in ulcerative colitis, which is why the antispasmodics people mention in threads are being used on a mechanistic hunch rather than on evidence. That is a question for your own clinician, not something to try on your own.

The trigger volume drops in proportion to how inflamed you are. A prospective study combined high-resolution anorectal manometry with rectal barostat testing in 36 people with active ulcerative colitis and 10 healthy volunteers. The Mayo endoscopic subscore correlated inversely with the volume at which people first felt a desire to defecate (rho = -0.41, p = 0.014) and with the maximum volume they could tolerate (rho = -0.53, p = 0.001) (Sanchis Martínez 2026). The more inflamed the lining looked, the less it took to set off the alarm.

And it is not only the inflammation. In a study of 33 people with recurrent ulcerative colitis and 40 newly diagnosed patients, a high faecal calprotectin was independently associated with a lower initial sensation threshold, a lower defecation volume threshold and a lower maximum capacity threshold (Wu 2024). A higher anxiety score was independently associated with the defecation volume threshold too, which we come back to below.

Put those together and the experience makes physical sense. A smaller container plus an earlier alarm equals repeated trips that produce a teaspoon of mucus. Our guide to urgency in ulcerative colitis goes through the same anorectal mechanics in more depth, because they drive both symptoms; the difference is that urgency is about the warning time and tenesmus is about the false alarm.

How common is tenesmus? Between 15% and 83%, depending on who you ask

There is no single defensible prevalence figure, and the honest version of this section is the spread rather than a number.

• 83.3% in active disease. In the prospective anorectal function study, 30 of 36 people with active ulcerative colitis reported tenesmus (Sanchis Martínez 2026).
• About half after treatment. The same study reported 51.6% still symptomatic four to six months later. Note the denominator changes: 83.3%, 91.7% and 66.7% are all fractions of 36, while 51.6%, 54.8% and 32.3% are fractions of 31. Five people are missing from the follow-up percentages, and the abstract does not say so. The direction of travel is still clear, but the two sets of percentages are not computed on the same group.
• 47.6% in a mixed IBD registry. In a single-centre registry of 383 patients with inflammatory bowel disease, 47.6% of the 353 who did not use cannabis reported tenesmus (Coates 2022).
• 45% in a questionnaire series. 32 of 71 people with inflammatory bowel disease (Petryszyn 2018).
• A similar share of people still report urgency. Worth saying plainly, because the threads and several health pages call tenesmus "the last symptom to go": in that same study, after treatment, 54.8% still reported urgency against 51.6% reporting tenesmus. On those numbers tenesmus is not uniquely persistent. It is one of several rectal symptoms that outlast the bleeding.
• 15.7% when the physician fills in the form. In a cross-sectional survey across six countries, physicians reported tenesmus in 15.7% of 221 patients with isolated proctitis (Armuzzi 2026). This study was conducted through the Adelphi Real World disease-specific programme, has Pfizer employees among its authors, and Adelphi was a paid consultant to Pfizer for the manuscript.

The evidence gap, measured

It is worth being concrete about how thin the literature is, because it changes how much weight any single number can bear.

Searching Europe PMC on 27 September 2026 for papers with "tenesmus" in the title and restricted to MEDLINE returned 53 records. Reading them, the field is made almost entirely of case reports, palliative care, and veterinary medicine: a dog with partial colorectal obstruction, an aortic dissection, a portosystemic shunt, a prostate cancer recurrence. Adding a requirement that "colitis" appear in the abstract left exactly one paper, and it is a case report of a 13 year old with an inflammatory cloacogenic polyp (Aguillera 2024). The same search shape for "urgency" plus colitis returned 50 papers.

That is one database, one query form, one day. It is not proof that no such literature exists, and a symptom can be well studied inside papers that do not name it in the title. But the contrast with urgency is stark, and it is not an accident. Bowel urgency acquired a validated numeric rating scale, entered clinical trial programmes and became something a manufacturer could make a labelling claim about. Tenesmus did not. We cover the urgency instrument and its funding in the urgency guide.

Tenesmus is in none of the scores, and that costs you something specific

The two-item patient-reported outcome used across ulcerative colitis trials, PRO-2, consists of stool frequency and rectal bleeding, both taken from the Mayo Clinic Score (Jairath 2015). That is the whole instrument. Our guide to the PRO-2 score works through what each number means and what "normal for you" is quietly doing in the frequency item.

The Simple Clinical Colitis Activity Index, the score most often used in clinic and in self-monitoring, was published as five clinical criteria plus extracolonic features (Walmsley 1998). A later item response theory analysis of 516 patients called it a nine-item scale, counting each extracolonic feature separately, and after systematic item deletion concluded that a four-item version carried more information: bowel frequency by day, bowel frequency at night, urgency of defecation and rectal bleeding (Walsh 2021). A separate validation study confirms general wellbeing as another of its items (Bewtra 2014). Note that even the item count is reported two different ways in the literature.

What matters here is that tenesmus was never a candidate item in either version. The field is stripping items out, not adding this one in. We checked PRO-2, the Mayo-derived patient items and the Simple Clinical Colitis Activity Index directly. We have not audited every colitis index ever published, so read this as "not in the scores your clinic uses" rather than a claim about all of them.

The counting problem nobody answers

This is the most practical question in the Reddit threads and it has no published answer: when you make a trip and nothing comes out, does that count in your stool frequency?

Read the instruments literally and it does not. The item is stool frequency; a trip producing nothing is not a stool. That means a person having twelve empty trips a day and two normal bowel movements can report a stool frequency that looks close to their baseline, score low on PRO-2, and be told their colitis is quiet.

Read it loosely and it does count, in which case your frequency number inflates, and a clinician reading it may escalate treatment on the strength of a number that is measuring sensation rather than output.

Neither is satisfying, and the honest fix is to refuse the single number:

1. Log productive trips and empty trips as two separate counts. Label them in plain words.
2. Note what came out on the empty trips. Nothing, gas, mucus, mucus with blood, a smear of stool. These are different pieces of information and blood belongs in a different conversation.
3. Log how long the sensation lasts after the trip. Settles within a minute, or nags for an hour. That distinction does more to convey severity than the count does.
4. Score the score honestly, then annotate it. Give the number the instrument asks for, then add one line: "PRO-2 stool frequency 1; separately, 9 to 12 non-productive trips a day."

Our guide on building a symptom record a clinician will actually read covers what survives a ten minute appointment, and the short version is that one annotated line beats a spreadsheet.

Does tenesmus mean my rectum is still inflamed?

Usually it points there, but it does not prove it, and its absence does not prove healing either.

The strongest evidence on this is uncomfortable. In the prospective anorectal study, barostat measurements remained abnormal compared with healthy volunteers after treatment, including in the patients who had achieved histological remission (Sanchis Martínez 2026). The lining had healed on biopsy and the organ still behaved differently. With 36 patients and four to six months of follow-up this is a signal, not a settled fact, but it is the clearest published answer to why the symptom lags behind the scope.

A separate study looked at 50 people with ulcerative colitis in documented remission or mild activity who had persistent defecatory symptoms, and used high-resolution anorectal manometry on all of them. Faecal incontinence was associated with disease duration (p = 0.008), while constipation, urgency, incomplete evacuation and rectal pain showed no significant relationship with disease duration, disease extent or the treatment used (Abdel Aty 2025). The authors conclude that defecatory disorders persist in quiescent colitis, which is a reasonable reading.

What that study cannot do, despite its title, is tell you the prevalence of defecatory disorders in quiescent ulcerative colitis. Every patient was enrolled because they already had persistent defecatory symptoms. A cohort selected on the symptom cannot estimate how often the symptom occurs. We have used it for the finding that these problems are not explained by disease extent or treatment, and not for any prevalence claim.

There is also a real middle category between "inflamed" and "healed". A prospective study of 150 people starting biological therapy used a modified endoscopic score that accounts for how much of the colon is involved, and found a group with segmental endoscopic response only, whose long-term outcomes sat between those with full endoscopic improvement and those with none (Lenfant 2024). Partly better is a real state, and if the segment that is still involved is the rectum, the symptom that persists will be a rectal one.

The practical route through all of this is not reasoning, it is measuring. Our guides to what calprotectin numbers mean in ulcerative colitis and to working out whether you are flaring cover how to get an answer rather than an inference.

The constipation question, and the syndrome that has a name

One of the most confusing experiences in ulcerative colitis is being constipated and having an urgent empty rectum at the same time. It is common enough that researchers have proposed a name for it.

In a cross-sectional series of 125 consecutive patients with ulcerative colitis, 58 (46%) met a working definition of constipation occurring with other abdominal symptoms, which practitioners commonly call proximal constipation. The authors note plainly that the syndrome "is poorly described, with no recognized definition", and propose calling it ulcerative colitis-associated constipation syndrome (James 2018).

The detail that matters for tenesmus is which symptoms made up the syndrome: reduced stool frequency in 69%, hard stools in 43%, abdominal pain in 40%, excessive flatus in 29%, straining in 24%, and a sensation of incomplete emptying in only 14%. So this is mostly a transit and consistency problem occurring above the inflamed segment, not the same thing as the rectal false alarm. The risk of it went up with female sex (odds ratio 3.45, 95% CI 1.45 to 8.24), left-sided disease (2.84, 1.14 to 7.11) and concurrently active disease (5.56, 1.96 to 16.67).

We checked those three intervals against their point estimates. The first two are exactly consistent: the geometric mean of 1.45 and 8.24 is 3.46, and of 1.14 and 7.11 is 2.85. The third is not: the geometric mean of 1.96 and 16.67 is 5.72, not the 5.56 reported. That is a small discrepancy, the kind that comes from rounding or from a non-Wald interval, and we could not tell which from the abstract. All three intervals exclude 1, so all three associations are statistically significant as reported, and the conclusion stands.

Crohn's disease can produce the same confusing combination for different reasons, and our guide to Crohn's with constipation rather than diarrhoea covers why a narrowed segment changes the picture there.

The threads describe the overlap the same way the paper does. In the constipation-versus-tenesmus thread, several people said the two coexist during a flare, and the most useful distinguishing detail offered was what comes out: globs of mucus and blood with tenesmus, nothing at all with constipation (r/UlcerativeColitis thread). Another person described the vicious cycle of the urge with nothing but mucus or pencil-thin stool. One reply put the safety point better than we could: they are two separate things that can happen at the same time, so see your doctor.

What the treatment evidence is actually about, and what it is not

The general principle is uncontroversial: inflammation in the rectum is treated where it is, from below. Topical mesalazine is described in the trial literature as the standard treatment for proctitis (Kruis 2019). None of what follows is a recommendation about any specific product, and none of it is dosing advice; these are the things worth raising with your own team, who know your disease extent and your history.

The largest proctitis trial we found did not measure tenesmus. A double-blind trial randomised 337 people with active proctitis to four different suppository regimens. Its primary endpoint was time to resolution of clinical symptoms, defined as the first of three consecutive days with a score of zero for rectal bleeding and stool frequency. That took a mean of 29.2 days on 1 g mesalamine, 29.8 days on 4 mg budesonide, 29.3 days on the combination, and a significantly longer 35.5 days on the lower 2 mg budesonide dose (Kruis 2019). Those are the best-quality timelines in the field, and they are timelines for two symptoms that are not the one this article is about. Anyone quoting you a confident number of weeks for tenesmus has extrapolated it.

How far up the drug actually goes has barely been studied since 1992. Two scintigraphy studies from that year are still the reference. In seven patients, five of whom were in remission, a median of 86% of a labelled enema had spread beyond the rectum within two hours (range 57% to 90%), though in one patient with a tortuous sigmoid it never got past it even at eight hours (Almer 1992). Five of seven being in remission matters, because an inflamed, spastic colon is not the one that was measured. In a crossover comparison in 10 patients, foam reached the upper limit of disease in every case while liquid enema failed in two, and foam distributed more uniformly (Campieri 1992). Seven and ten patients respectively, thirty-four years ago. This is the evidence base for a decision people make every night.

When suppositories are not enough, the trial results are honest about being modest. A randomised double-blind trial in 85 people with proctitis refractory to 5-ASA compared tacrolimus with beclomethasone suppositories over four weeks. Clinical response was 63% versus 59% (p = 0.812) and clinical remission 46% versus 38% (p = 0.638), with no significant differences, including in adverse events (Lie 2020). The authors read this as two usable options rather than a winner. Worth being precise about what that means: this was a trial designed to look for superiority, and failing to find a difference between two arms is not the same as demonstrating they are equivalent.

A retrospective series of 38 patients treated with acetarsol suppositories reported clinical response in 26 (68%), in a group that had failed a broad range of topical and systemic treatments (Kiely 2018). There was no control arm, so the 68% cannot be attributed to the drug; in a refractory group some of it will be regression to the mean and the natural waxing and waning of colitis. It is a signal worth having, not an effect size.

Refractory proctitis is not rare, and the numbers need care. A retrospective cohort of 185 people with ulcerative proctitis across three South Australian hospitals found 62.3% achieved treatment success with 5-ASA therapy while 56 (30.3%) developed refractory disease, and 34 (18.4%) developed complications, split between proximal disease extension in 22 (11.9%) and hospitalisation in 15 (8.1%) (Raja 2026). Two figures in that abstract do not add up. One colectomy in 185 patients is reported as "0.05%", but 1 divided by 185 is 0.54%, an order of magnitude out. And the 114 patients who succeeded on 5-ASA are 61.6% of 185, not the 62.3% stated, which implies the denominator for that figure was 183 rather than the full cohort. Neither error changes the headline, and we have used the counts rather than the percentages.

A separate single-centre cohort of 230 patients with proctitis found 50 (21.7%) refractory, and on multivariable analysis the only significant predictors were use of topical steroids (odds ratio 4.0, 95% CI 1.13 to 14.13, p = 0.031) and endoscopic severity at diagnosis (5.23, 1.04 to 26.27, p = 0.044) (Borkovsky 2026). Both confidence intervals are consistent with their point estimates. But "topical steroid use predicts refractory disease" is almost certainly confounding by indication: you are prescribed rectal steroids because you are already worse. The paper presents it as a predictor without saying that, and it is not a reason to avoid a treatment. Its subgroup percentages also do not use the stated group sizes. The rectal steroid figures of 48.9% and 17.3% work out to 24 of 49 and 31 of 179, not of 50 and 180, so a patient is missing from each arm. More importantly, the endoscopic severity figures of 87.5% and 59.2% are 21 of 24 and 45 of 76, meaning endoscopic scores were available for 100 of the 230 patients. The abstract does not say that, and it is the variable the paper's headline finding rests on.

A Spanish systematic review and expert consensus reached a similar bottom line: it included 43 articles of low to moderate quality, found nearly 30% of patients had refractory proctitis with a highly significant impact on quality of life, and identified explicit gaps in the evidence on clinical course, efficacy and treatment selection before issuing 13 practical statements (Barreiro-de Acosta 2026).

The paradox nobody has studied

Here is the problem the threads identify and the literature does not. The treatment best matched to rectal inflammation is the one delivered rectally. But a rectum that is inflamed enough to produce constant tenesmus is also a rectum that cannot comfortably hold an enema for long enough for it to work. One commenter in a thread asking for solutions laid it out exactly: enemas and suppositories are an option, but how are you supposed to hold them in when the rectal inflammation is what makes holding anything difficult (r/UlcerativeColitis thread).

We searched for trial or cohort data on enema and suppository retention in active proctitis and could not find any. The distribution studies above measured spread in patients who managed to retain the dose; they say nothing about the people who could not. The Kruis trial reported treatment acceptance of 67% to 85% across its four suppository arms, which is the closest thing to a tolerability figure we located, and acceptance is not the same measurement as retention (Kruis 2019). If this has been studied properly, our searching did not surface it.

That is a genuine gap, and it is worth naming in an appointment. "I cannot hold the enema" is a treatment-limiting problem with practical workarounds a clinician can suggest, including formulation and timing; it is not a failure of effort.

When tenesmus is not your colitis

This is the section that is missing from almost every page on the subject, and it matters most for the people whose colitis is objectively quiet.

A few of these deserve more than a table row.

Levator ani syndrome hides behind the word "diarrhoea". A 2025 case series described two patients, aged 25 and 32, who presented with "diarrhoea" and perianal sweating. Taking a proper history revealed rectal discomfort, tenesmus, urgency and a sensation of incomplete evacuation, and a digital rectal examination found puborectalis tenderness in both. The authors note that levator ani syndrome accounts for up to 7.4% of anorectal pain cases (Gupta 2025). A two patient series proves nothing about frequency, but the diagnostic lesson is free: the distinguishing sign is found by an examination that takes a minute.

Dyssynergic defecation is treatable and often missed. It affects up to half of people with chronic constipation, requires anorectal physiology testing plus a balloon expulsion test to diagnose, and randomised trials have shown biofeedback therapy more effective than laxatives in both the short and long term (Rao 2016b). Rome's own criteria require both symptoms and objective evidence, which is why the test is not optional (Rao 2016). Do not confuse this with biofeedback for irritable bowel syndrome, where a Cochrane review of eight trials in 300 adults judged all of them at high or unclear risk of bias and rated the evidence for global improvement very low certainty (Goldenberg 2019). Different condition, different evidence.

Sexually transmitted proctitis is the one that is genuinely dangerous to miss, because it is treated with antibiotics and because escalating immunosuppression for it is the wrong move. A review of the topic lists faecal urgency, purulent or bloody discharge, anorectal pain and tenesmus as the commonest presentations, and the commonest pathogens as gonorrhoea, chlamydia, syphilis and herpes simplex (Bejarano Rengifo 2020; Sigle 2015). It can be histologically hard to separate from colitis: in a cross-sectional study of 54 patients whose biopsies were compatible with sexually transmitted proctitis, the commonest endoscopic finding was rectal ulcer in 61%, and the commonest histology was basal lymphoplasmacytic inflammation with mild crypt distortion, which is uncomfortably close to what early colitis looks like. Chlamydia was identified by immunohistochemistry in 40%, which the authors report as 18 of 45 tested rather than 18 of 54, a distinction worth noting before repeating the percentage (Arévalo 2022). The three chronic proctitis syndromes most often confused with each other, ulcerative proctitis, chronic radiation proctopathy and diversion proctitis, have their own review, and the authors are explicit that their differential can be problematic when the causes overlap (Wu 2015).

Solitary rectal ulcer syndrome is a benign condition mistaken for both colitis and cancer. A 2026 narrative review describes it as a disorder of varied clinical, endoscopic and histological appearance that is often misdiagnosed as inflammatory bowel disease or rectal malignancy, with contributing factors including mucosal prolapse, ischaemia, paradoxical puborectalis contraction and digital trauma. Diagnosis needs history, digital rectal examination, endoscopy, histopathology and physiological studies together, and the authors note that standardised treatment protocols do not yet exist (Prabagar 2026). The paradoxical puborectalis contraction is what ties it to the pelvic floor diagnoses above.

A normal-sounding colonoscopy does not always rule out an anorectal lesion. The one paper our search found with tenesmus in the title and colitis in the abstract is a case report of a 13 year old whose inflammatory cloacogenic polyp was only found at the second endoscopy within a year, when rectal retroflexion was performed. The authors' point is that lesions at the anorectal transitional zone belong in the differential for anything that looks like distal colitis (Aguillera 2024).

And very occasionally it is not the bowel at all. A 69 year old woman presented to an emergency department with gastrointestinal symptoms including rectal tenesmus and was found to have a Stanford type A aortic dissection. Her presentation had been delayed by 12 hours because the tenesmus was attributed to irritable bowel syndrome (Fratczak 2024). This is a single case report and vanishingly rare. It is here for one reason: sudden severe tenesmus arriving with chest, back or abdominal pain in someone who has never had it before is not a colitis problem.

What about cancer?

Tenesmus is a recognised symptom of rectal cancer, and new unexplained tenesmus in someone without a bowel diagnosis should be assessed. But we could not find a study giving tenesmus its own positive predictive value in primary care, so any page telling you the percentage chance that your tenesmus is cancer has produced that number from somewhere other than the literature we could locate.

What has been quantified is new rectal bleeding. In a 10 year prospective study in one UK general practice, 265 patients aged 45 or over reported new onset rectal bleeding; 15 (5.7%, 95% CI 3.2% to 9.2%) had colorectal cancer and 13 (4.9%) had a colonic adenoma, and only two of the cancer patients had diarrhoea (du Toit 2006). One general practice and one decade is a narrow base, and the authors' conclusion was that everyone in that group should be offered bowel investigation.

If you already have ulcerative colitis, that number does not transfer to you, because bleeding is an expected feature of your disease. The useful rule is about change: a new pattern, a symptom that does not fit your usual flare, tenesmus that persists while everything else has settled, or anything accompanied by weight loss. Those get assessed, not assumed. Your team already has a surveillance plan for cancer risk in long-standing colitis; this article is not a substitute for it.

Is it psychological?

No, and the question deserves a straight answer because it comes up constantly. One person on a JAK inhibitor described exactly this doubt: everything else had settled, tenesmus had not, it varied with their surroundings, and they wondered whether it was partly psychological while also being sure it was real (r/UlcerativeColitis thread).

Both halves of that are right. The mechanics are measurable, on manometry and barostat, in people who are not reporting them (Sanchis Martínez 2026). And the gut-brain loop is real: in the recurrent colitis study, a higher anxiety score was an independent determinant of the defecation volume threshold alongside faecal calprotectin (Wu 2024). Anxiety can lower the volume at which you notice the signal. That is a modifier of a physical sensation, not an invention of one.

It is also worth knowing that clinicians have argued about whether symptom scores in colitis measure inflammation or mood, specifically about the Simple Clinical Colitis Activity Index (Gracie 2016). That debate is a reason to pair your symptoms with a calprotectin test, not a reason to doubt yourself.

Two other things get raised in the threads and are worth answering honestly.

Cannabis. Community threads describe it relaxing the spasm and breaking the cycle. The one IBD dataset we found that actually counted tenesmus points the other way: in a registry of 383 patients, the 30 active cannabis users reported more tenesmus than non-users (70.0% versus 47.6%), along with more abdominal pain, gas and joint pain, while the rate of moderate to severe endoscopic inflammation was similar in both groups (Coates 2022). This is cross-sectional data on 30 people, so it cannot tell you which came first, and the most likely reading is that people with worse symptoms are more likely to use cannabis. It certainly does not show that cannabis makes tenesmus worse. What it does show is that there is no published evidence here supporting the community claim, and the only relevant numbers run in the opposite direction.

Whether this is really irritable bowel syndrome overlap. It can be, and IBS-type symptoms are common in colitis remission. But do not let anyone treat that as a reason to reach for a rectal anti-inflammatory as a test: a randomised trial of 181 people with IBS found mesalazine no better than placebo on its primary endpoint (36% versus 30%, p = 0.40), and a post hoc meta-analysis found no effect on IBS symptoms at all (Castro Tejera 2022). That trial's funders included Eurostars and Tillotts Pharma, a pharmaceutical company, and it still reported a null result. Our guide to symptoms that persist in remission covers the overlap in full.

Why tenesmus after surgery is normal, and still worth reporting

Several threads include people who assumed that removing the colon would remove the sensation and were frightened when it did not. It usually does not, and the reason is anatomical: in most operations the rectum, or a cuff of it, stays behind.

A defunctioned rectum gets inflamed. In a prospective study of 18 patients who had faecal diversion and, importantly, did not have inflammatory bowel disease, diversion was associated with visible inflammation in 55% and inflammation on biopsy in 72%, with a variable pattern of small ulcers, crypt abscesses and nodularity. In the 10 patients whose continuity was restored, histological features improved in all of them but the mucosa returned to fully normal in only 50% (Winslet 1993). The authors note that the only reliable diagnostic feature of diversion proctitis is that it resolves when the faecal stream is reintroduced.

In colitis specifically, a review of 281 patients having staged pouch surgery found diversion proctitis on the proctectomy specimen in 68 (24.2%), and those patients were significantly more likely to have needed rectal therapy between the first and second operations (32.4% versus 19.2%, p = 0.02). Reassuringly, diversion proctitis was not associated with later cuffitis (19.1% versus 14.1%, p = 0.32) (Dharia 2026).

After a pouch, cuffitis is common. In a multicentre cohort where the pouch-anal anastomosis was described in 674 pouchoscopy reports, 525 had a stapled anastomosis and cuffitis occurred in 313 of those (59.6%), at a median of 1.51 years after the final surgical stage (Posner 2025). A narrative review of 23 studies found mesalamine and corticosteroid regimens were the best studied and produced symptomatic improvement in 52% to 100% of patients, although those studies ranged from 4 to 120 patients, so the 100% end of that range is a very small denominator. Data on advanced therapies and procedures came from studies of one to 21 patients and were inconsistent (Powers 2025). Pelvic floor function may matter here too: abnormal preoperative anorectal manometry was associated with modestly increased odds of later cuffitis (odds ratio 2.136, 95% CI 1.050 to 4.345, p = 0.037), and the authors are careful to say the effect size is modest and the precision limited (Dester 2026).

One person in a thread described exactly this after a colectomy: the same urgent rectal pain they had before surgery, which their ostomy nurse explained was the mucus a retained rectum keeps producing, and which became painless once they stopped resisting the urge to pass it (r/UlcerativeColitis thread). That is one person's experience, not advice. The general point stands: without a colon, the usual colitis reasoning does not transfer cleanly, and a persistent rectal symptom after surgery should be looked at rather than endured.

A worked example: two people, both "still getting tenesmus at three months"

Both started treatment for left-sided colitis twelve weeks ago. Both say the same sentence in clinic. They need opposite things.

Person A. Bleeding stopped at week three and has not come back. Two formed bowel movements a day. Six to nine empty trips, mostly in the first three hours after waking, usually producing a smear of clear mucus. The urge settles within a minute of passing the mucus. No night waking. Faecal calprotectin 60 µg/g last week, down from 900.

The pattern here looks like a rectum that is healing but has not recovered its capacity or its sensory threshold, which is the situation the barostat data describe. The useful conversation is about whether topical treatment continues, what a realistic timeline looks like given that nobody has measured this endpoint, and whether the morning clustering is worth working with rather than against.

Person B. Bleeding never fully stopped. One or two formed bowel movements a day, so the stool frequency item reads almost normal. Twelve to twenty empty trips, several of them producing mucus streaked with blood, two of them at night. Deep rectal pain lasting 20 to 40 minutes after each trip. Calprotectin 480 µg/g.

Here the individual PRO-2 items understate the situation badly, and the symptoms that are carrying the information, night waking, blood on the empty trips and prolonged post-trip pain, are all outside the score. The first move is not to reason about it; it is to contact the IBD team with those three facts in one sentence.

The difference between A and B is not the sentence they said. It is the detail underneath it, and whether anyone wrote it down.

What to track, and what to leave out

Everything useful about tenesmus is in the shape of the day, not in a single number.

• Two counts, labelled. Productive bowel movements; separately, non-productive trips.
• What came out on the empty trips. Nothing, gas, clear mucus, mucus with blood, a smear of stool. Blood changes the conversation.
• Whether the urge settles after the trip, and how fast. "Settles in a minute" and "nags for half an hour" are different diseases from a clinician's point of view.
• Time of day and night waking. Morning clustering is extremely common in the threads. Waking at night is a different signal and belongs in the urgent column.
• Pain: whether it exists, how long it lasts, and where it is. Deep rectal, tailbone, perineal. If it lasts more than 30 minutes and sitting makes it worse, that is worth saying out loud, because it is part of the definition of a different diagnosis.
• What you were doing. Not to hunt for food triggers, which is a poor use of effort for a rectal symptom, but because a straining-and-just-in-case-trips pattern is worth noticing. One person wondered aloud in a thread whether all the precautionary pre-emptive trips were themselves wearing down their control (r/UlcerativeColitis thread). Nobody has studied that, but it is a reasonable thing to log and discuss.

Leave out the long food diary for this particular symptom. Tenesmus is a rectal mechanics and inflammation problem, and the thread evidence is consistent with the mechanism: one person reported trying to cut out foods with little success because it happened regardless of what they ate (r/UlcerativeColitis thread).

If you want that split count without keeping two tallies in your head, Clairop logs bowel movements alongside symptoms and produces a one-page summary for an appointment, which is the format most likely to survive a ten minute slot.

How to describe it so it lands

The sentence "I feel like I need to go all the time" is accurate and it gets you nowhere, because it sounds like frequency and frequency is already on the form. Replace it with counts and durations.

Instead of "I still have tenesmus", try:

"My stool frequency is one or two a day, and separately I make nine to twelve trips where nothing comes out except clear mucus. Most of them are in the first three hours after I wake up. The urge settles within a minute after the mucus. It does not wake me at night, and there has been no blood for six weeks."

That paragraph contains a stool frequency, a separate non-productive count, a temporal pattern, a duration, a negative for night symptoms and a negative for bleeding. It takes 20 seconds to say. Our guide to preparing for a gastroenterology appointment covers how to get a sentence like that heard in the room, and our list of questions worth asking a gastroenterologist about colitis covers what to do with the rest of the slot.

Myths about tenesmus in ulcerative colitis

"Tenesmus just means you are constipated." No. Constipation is stool that will not move; tenesmus is an urge with nothing to move. They can coexist, and when they do there is a described syndrome for it (James 2018), but they are not the same problem and they do not have the same answer.

"If your colitis score is fine, your rectum is fine." The scores we checked contain no tenesmus item. PRO-2 has two items and neither is this (Jairath 2015); the Simple Clinical Colitis Activity Index has urgency but not tenesmus (Walsh 2021). A tidy score with an unliveable day is a documented combination, not a contradiction.

"It always disappears in remission." Often it improves enormously. But about half of the patients followed in the prospective anorectal study still reported it at four to six months, and the organ's measured behaviour was still abnormal in people who had reached histological remission (Sanchis Martínez 2026).

"There is a known average duration." There is not, because almost nobody has measured it as an endpoint. The 29 day figure people sometimes see is time to resolution of bleeding and stool frequency in a suppository trial, not tenesmus (Kruis 2019).

"It is anxiety." The rectal sensitivity and capacity changes are measurable with instruments (Drewes 2006; Sanchis Martínez 2026). Anxiety appears in the data as a modifier of the threshold, not as the cause (Wu 2024).

"Cannabis fixes it." The only IBD dataset we found that counted tenesmus reported it more often in cannabis users, not less (Coates 2022). That does not mean cannabis is harmful here; it means the community claim has no supporting evidence that we could find.

"A colonoscopy has ruled everything out." Usually true, with two caveats: a lesion at the anorectal junction can be missed unless the scope is retroflexed in the rectum (Aguillera 2024), and a normal-looking lining does not exclude a pelvic floor diagnosis, which needs manometry and a balloon expulsion test rather than a camera (Rao 2016).

"Pushing harder will empty it." Straining against an empty inflamed rectum is how people acquire haemorrhoids and fissures, which then produce their own tenesmus. Several threads describe exactly that sequence.

When to see a doctor promptly

Tenesmus on its own, in someone with known colitis whose other symptoms are settling, is usually a rectum catching up. These are the situations that are not that. Contact your IBD team or seek urgent care rather than waiting for a routine appointment if you have:

• New or increasing blood on the empty trips, or blood that had stopped and has come back
• Tenesmus that wakes you from sleep, which is a signal that belongs in the urgent column
• Six or more bloody stools a day, a fever, a fast heart rate or feeling generally unwell, which together point at severe colitis needing assessment now
• Unexplained weight loss, a new anaemia, or unexplained fatigue alongside the rectal symptoms
• Sudden severe tenesmus with chest, back or abdominal pain, especially if new, which needs emergency assessment and not a bowel appointment
• New tenesmus without a bowel diagnosis, particularly over 50 or with a family history of bowel cancer or inflammatory bowel disease
• Tenesmus with anorectal discharge, ulcers or pain after a possible sexually transmitted exposure, because that is treated with antimicrobials rather than immunosuppression
• Tenesmus persisting long after everything else has settled, which is worth investigating for a pelvic floor cause rather than accepting
• A new or changed rectal symptom after pouch or stoma surgery, which is usually treatable and should not be endured

And if you have been told the problem is nothing because your score is normal, that is worth a second conversation. The score does not contain the symptom.

The honest bottom line

Tenesmus in ulcerative colitis is a rectal signalling problem. A hypersensitive lining, a smaller reservoir and a lower trigger volume mean the alarm goes off on almost nothing, and no amount of willpower changes any of the three. When the rectum is inflamed, treating it where it lives is the logical move, and the trial evidence for topical treatment in proctitis is decent for bleeding and frequency and silent on tenesmus itself.

What makes this symptom uniquely frustrating is not the physiology. It is that the instruments used to decide whether you are doing well do not contain it, the research literature has barely looked at it, and the surveys that exist suggest clinicians record it far less often than patients report it, even allowing for the fact that those surveys asked different populations. So the most useful thing you can do is refuse to let it disappear into a stool frequency number. Count the empty trips separately, say what comes out, say how long the feeling lasts, and bring those three facts to the appointment.

And if your colitis is objectively quiet and the sensation has not moved, stop reasoning about inflammation and ask about the pelvic floor. Levator ani syndrome, dyssynergic defecation and rectal hypersensitivity are all named diagnoses with their own tests and their own treatments, and all three produce a feeling indistinguishable from the one you have been attributing to colitis.