Digestive Health Irritable Bowel Syndrome Rectal Tenesmus Symptoms, Causes, and Treatment The sensation of being unable to empty the bowel By Barbara Bolen, PhD twitter Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome. Learn about our editorial process Barbara Bolen, PhD Medically reviewed by Medically reviewed by Emmy Ludwig, MD on October 23, 2018 Emmy Ludwig, MD, is board-certified in gastroenterology and hepatology. She practices at the Memorial Sloan-Kettering Cancer Center in New York. Learn about our Medical Review Board Emmy Ludwig, MD Updated on October 13, 2020 Print Table of Contents View All Symptoms Causes Diagnosis Treatment Tenesmus is a medical term used to describe the sensation of being unable to empty your bowel after you have already defecated. Tenesmus is commonly associated with inflammatory bowel disease (IBD) but may also be caused by hemorrhoids, infections, and even cancer. Laurence Dutton / Getty Images The diagnosis may involve a stool culture, blood tests, colonoscopy, or a biopsy to identify the underlying cause. Pain medications and antispasmodics may be prescribed to help alleviate symptoms while the underlying cause is being treated. Symptoms Symptoms of tenesmus may be constant or intermittent but usually involve some or all of the following: Rectal painGasBloatingCrampingItchingRectal dischargeRectal bleedingInvoluntary straining When to Call a Doctor Urgent care should be sought if tenesmus is accompanied by high fever (over 100.4 F), chills, severe rectal bleeding, nausea, vomiting, or fainting. Is Rectal Itching a Sign of Cancer? Causes The cause of tenesmus is not well understood, but it is believed that inflammation or irritation may stimulate both somatic nerves (that instigate physical sensations) and autonomic nerves (that modulate smooth muscle contractions) in the bowel. Overstimulation of these nerves may not only make it feel as if there is residue within the bowel but can also trigger contractions that we recognize as the onset of a bowel movement. In addition, severe diarrhea or constipation can also cause scarring of bowel tissues. If this happens, it not only makes passing stools more difficult, but it can feel as if there is more in the bowel than there actually is. Sores or growths around the rectum or in the colon can do the same. There are numerous conditions that can trigger tenesmus, including: Celiac disease Chronic constipationChronic diarrheaColorectal cancerCrohn's diseaseDiverticular diseaseGastroenteritisIrritable bowel syndrome (IBS)Ischemic colitisPelvic floor disordersProlapsed hemorrhoidRectal abscessRectoceleSexually transmitted proctitis (including gonorrhea, chlamydia, or syphilis)Ulcerative colitis Tenesmus can also affect people who have undergone radiation therapy for cervical cancer, rectal cancer, prostate cancer, or colon cancer (a condition referred to as radiation proctitis). Common Causes of Rectal Pain Diagnosis Tenesmus is not a medical condition but rather a symptom of a condition. As such, your doctor will want to uncover the underlying cause by first reviewing your medical history, family history, and current symptoms. This would likely include questions about your bowel habits, diet, and lifestyle. Based on these diagnostic clues, your doctor will want to perform tests to explore the more likely causes, like IBS, or exclude potentially serious ones, like rectal cancer. Physical Exam The physical exam is essential to the diagnosis of tenesmus. It helps the doctor see if there is any inflammation or abnormalities around the rectum, tenderness or pain in the abdomen, or signs of a sexually transmitted infection. The procedure may involve a digital rectal exam (DRE). This involves the insertion of a gloved finger into the anus to check for hemorrhoids, blood, mucus discharge, infection, or abnormal growths. Serious and Benign Causes of Rectal Bleeding Lab Tests After the physical exam, the doctor will commonly order a battery of blood and stool tests to help narrow down the causes. These may include: Complete blood count (CBC): A battery of tests that can help detect infection (characterized by an increase in white blood cells) or anemia (due to decreases in red blood cells), among other thingsErythrocyte sedimentation rate (ESR) and C-reactive protein (CRP): Blood tests that detect generalized inflammation associated with infections, inflammatory diseases, and other causesFecal blood occult: A test used to detect blood in a stool sampleStool culture: A test that checks for pathogenic (disease-causing) bacteria in a stool sampleSTD screening: A battery of tests used to detect gonorrhea, chlamydia, syphilis, and other sexually transmitted infectionsCarcinoembryonic antigen (CEA): One of several tumor marker tests that detects substances in blood suggestive of colorectal cancer Imaging Studies Before proceeding to more invasive procedures, the doctor may order imaging tests to help visualize the digestive tract. These may include: Barium X-ray: A type of X-ray in which a barium enema is used to highlight growths, obstruction, lesions, or perforation of the intestineComputed tomography (CT) colonography: An imaging technique involving multiple, composited X-rays that provide greater detail of the intestines, including the presence of polyps or tumorsMagnetic resonance imaging (MRI): A type of scan using powerful magnetic and radio waves to create highly detailed images of soft tissues within the digestive tract Procedures If colorectal cancer is suspected or an anomaly is spotted on imaging studies, the doctor may refer you to a gastroenterologist for an exploratory procedure to directly visualize the colon. These minimally invasive endoscopic procedures include: Colonoscopy: A procedure using a flexible scope, called a colonoscope, to examine the entire colonSigmoidoscopy: A version of colonoscopy limited to the lower part of the colon, called the sigmoid colonColon biopsy: Performed during a colonoscopy or sigmoidoscopy to obtain a sample of tissue for evaluation in the lab If colorectal cancer is the cause of tenesmus, the only test that can definitively confirm the diagnosis is a biopsy. Blood tests and imaging studies can support the diagnosis, but they cannot diagnose the disease. How Colon Cancer Is Diagnosed Treatment Tenesmus tends to improve once the underlying cause is identified and treated. Because the causes of tenesmus are so diverse, are the tenesmus-specific treatments. Cause Treatment Option Celiac disease Gluten-free diet Constipation Laxatives and stool softenersHigh-fiber diet Diarrhea Antidiarrheals like Imodium (loperamide) Colorectal cancer Opioid drugs for advanced cancerEndoscopic laser treatment Crohn's disease Corticosteroids like prednisoneAminocylates like Colazal (balsalazide)Immunosuppressants like methotrexateTNF blockers like Humira (adalimumab)Antibiotics like Flagyl (metronidazole)Surgery Diverticular disease High-fiber dietOral or intravenous antibioticsSurgery Gastroenteritis Antibiotics (if the cause is bacterial)Antiparastic drugs (if the cause is parasitic) IBS High-fiber diet Antispasmodics like Levsin (hyoscyamine)Anti-diarrheals or laxatives, as neededTricyclic antidepressants like amitriptyline Ischemic colitis AntibioticsSurgery, if bloodflow obstruction is severe Pelvic floor disorders Stool softenersPhysical therapyPercutaneous tibial nerve stimulation (PTNS)Surgery Prolapsed hemorrhoid Rubber band ligationSclerotherapyHemorrhoidectomy Rectal abscess Surgical drainageAntibiotics, including penicillin Rectocele Kegel exerciseIntravaginal pessarySurgery STDs Antibiotics (varies by infection) Ulcerative colitis Same as Crohn's disease A Word From Verywell While you may feel uncomfortable discussing tenesmus with your doctor, it is important to do so. This is especially true if the symptom is persistent, worsening, or accompanied by bleeding, tarry stools, narrow stools, weight loss, fever, vomiting, or the inability to defecate. None of these symptoms should ever be dismissed or ignored. Was this page helpful? Thanks for your feedback! One of the most challenging aspects of having IBS is trying to figure out what's safe to eat. Our recipe guide makes it easier. Sign up and get yours now! Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Petryszyn PW, Paradowski L. Stool patterns and symptoms of disordered anorectal function in patients with inflammatory bowel diseases. Adv Clin Exp Med. 2018;27(6):813-8. doi:10.17219/acem/68986 Quigley EMM. Disorders of the pelvic floor and anal sphincters; a gastroenterologist’s perspective. Revista Médica Clínica Las Condes. 2013 Mar;24(2):293-8. doi:10.1016/S0716-8640(13)70161-5 U.S. National Library of Medicine. Tenesmus. In: MedlinePlus. Updated June 21, 2018. Grodsky MB, Sidani SM. Radiation proctopathy. Clin Colon Rectal Surg. 2015;28(2):103-11. doi:10.1055/s-0035-1547337 Herrero JAV, Abdussalam A, Kasi A. Rectal exam. In: StatPearls. Updated July 1, 2020. Swiderska M, Choromańska B, Dąbrowska E, et al. The diagnostics of colorectal cancer. Contemp Oncol (Pozn). 2014;18(1):1-6. doi:10.5114/wo.2013.39995 Hristova L, Soyer P, Hoeffel C, et al. Colorectal cancer in inflammatory bowel diseases: CT features with pathological correlation. Abdom Imaging. 2013;38(3):421-35. doi:10.1007/s00261-012-9947-6 Morarasu S, Haroon M, Morarasu BC, Lal K, Eguare E. Colon biopsies: Benefit or burden?. J Med Life. 2019;12(2):156-9.