Key takeaways
- Colonic machines can be FDA-cleared only for medically needed bowel cleansing, such as before an X-ray, and none has been approved for routine “well-being” use.
- A colonic machine was the likely source of a parasite outbreak at a Colorado clinic that began in 1977, infecting at least 36 people and killing seven.
- A 2018 Canadian public health review of colon-cleansing injuries counted 33 bowel perforations, 13 of them fatal, and most happened in medical or institutional settings.
- In 2002, after no company sent requested safety data, the FDA barred aloe and cascara from over-the-counter laxative drugs; the rule didn’t address dietary supplements.
- NIDDK’s self-care advice for sluggish bowels is to add fiber slowly, drink plenty of fluids, stay active and set a regular bathroom time.
In December 1977, patients at a chiropractic clinic in Montrose, Colorado, started falling ill. The common thread was colonic irrigation1. In this kind of cleanse, a machine pumps water into the colon through a nozzle in the rectum4.
The illness was amebiasis, an infection caused by a parasite. New cases kept turning up until November 19801. Clinic patients who’d had colonics were far more likely to report bloody diarrhea: 20%, compared with 1% of other patients1.
Ten people developed holes in the bowel and needed part or all of the colon removed. Seven died1.
CDC investigators suspected the machine itself. Parasites from one patient’s waste may have reached the shared tubing used for the next person1. Lab samples backed that up. Taken after a standard cleaning, they grew heavy loads of bacteria from almost every part of the machine1.
The CDC’s March 1981 report described 13 cases backed by lab evidence. A later count put the total at 36 or more12. The outbreak led to a nationwide requirement that commercial clinics use disposable colonic kits, a 2018 Canadian review notes2.
Colon cleanses haven’t faded since. In 2025, gastroenterologists told a medical news outlet that patients still ask about colonics and detox teas. One said interest rises and falls with whatever is trending online6.
Our detox articles cover the big picture. This one focuses on the colon: what cleanses claim, what regulators allow, what goes wrong, and what to do instead.
The cleanse theory, as its supporters tell it
The core belief is old. Colon cleansing grew from the idea of “autointoxication,” the notion that waste sitting in the colon slowly poisons the body3.
Cleanse marketing adds numbers. One product has claimed that people carry 6 to 40 pounds of stuck waste13. Ads have also claimed that actor John Wayne died with 40 to 80 pounds of impacted matter inside him. No autopsy was ever done13.
The fix, in this view, is to flush the colon from below with water, or from above with herbs, fiber, clay or salt water. Fans say they feel lighter, clearer and more regular afterward.
Part of this rests on real experience. Constipation is miserable, and NIDDK’s self-care advice for it centers on fiber and a regular routine9. Wanting to feel clean inside is a reasonable wish.
The weak link is the middle step: the idea that a healthy colon stores toxic sludge that only a cleanse can remove. Your colon recycles water, hosts microbes and moves waste out on its own schedule. Our guide to how digestion works walks through it.
“Mucoid plaque” hasn’t turned up where doctors look
The most vivid cleanse claim is mucoid plaque. Richard Anderson, a naturopath with his own cleanse product to sell, coined the term13. Ads show users holding long, rubbery ropes they say came off their colon walls13.
Joe Schwarcz, of McGill University’s Office for Science and Society, notes that pathologists, colorectal surgeons and radiologists haven’t reported seeing this coating13. They are the specialists who examine colons most closely.
His likelier explanation is the cleanser itself. Many products contain fibers such as psyllium husk or guar gum, which swell with water13. With the wrong amount of fluid, they can leave the body as a long, slimy cast, and bentonite clay makes that more likely13.
That is an expert’s argument, not a formal study. But the burden of proof sits with the claim, and we found no medical study describing mucoid plaque as a real layer.
A 2011 review by Georgetown University family medicine authors went further. Searching the medical literature, they found no scientifically strong studies supporting colon cleansing at all3.
A colonic machine can be cleared for one job
The FDA’s rule for these machines sorts them by purpose4.
- Class II covers machines intended for “colon cleansing when medically indicated,” such as before an X-ray or an endoscopic exam4. Makers must notify the FDA before selling them, through a filing called a 510(k)6.
- Class III covers machines for any other use, “including colon cleansing routinely for general well being”4. Each needs FDA premarket approval before it can be sold for that purpose4.
The 2011 review reported that the FDA had never approved a colonic system for general cleansing. In 2025, an FDA spokesperson said that was still true36. So a machine at a wellness spa may be legally cleared, but only for medically needed bowel cleansing.
When sellers stretch the label, the FDA can step in. In 1997, its Dallas office warned a San Antonio, Texas, company about its colonic device, according to an archived copy of the letter5. The device had been cleared for medically indicated cleansing. The firm’s later labeling claimed help for acne, allergies, asthma, low-grade chronic infections and liver function5.
Those new uses required a premarket approval the company never sought, the FDA said, so the device was adulterated and misbranded under federal law5. By 2011, the review reported, the FDA had sent numerous warning letters over unapproved colon-cleansing uses3.
The person running the machine matters, too. Colonic practitioners aren’t licensed by a scientifically based body, the review notes3. Trade groups certify them instead, with requirements that include a high school diploma, three semesters of college-level study and CPR training3.
What goes wrong: the documented harms
Serious injuries seem to be rare. No one knows how rare, because little is known about how many colonics are done2.
The best tally we found comes from Canada’s National Collaborating Centre for Environmental Health. In 2018, its reviewers found 19 papers describing 47 injuries, not counting the Colorado outbreak2:
| Harm | Cases | What happened |
|---|---|---|
| Bowel perforation | 33 | A tear in the bowel wall; 13 people died, and delayed diagnosis made death likelier2 |
| Burns | 6 | All from hot water or hot coffee enemas people gave themselves at home2 |
| Electrolyte imbalance | 5 | Each needed emergency treatment; 2 people died, though the link to the colonic was unclear2 |
| Infection | 3 | The person’s own gut bacteria spread into blood or tissue; none passed between clients2 |
One surprise: 24 of the 33 perforations happened in medical or institutional settings2. Supervised irrigation carries risk, too. One study of 8.1 million medical irrigations estimated about 6 perforations per million procedures2.
The 2011 review adds case reports of back and pelvic abscesses, fatal air bubbles in blood vessels, gangrene near the anus and dangerous water overload3. Coffee enemas have their own record. A systematic review found nine case reports of harm, seven of them colitis, an inflamed colon. It found no study showing benefit6.
Some people face higher risk: those with a history of diverticulitis, Crohn’s disease, ulcerative colitis, colon surgery, severe hemorrhoids, kidney disease or heart disease3. The Canadian review adds spinal cord injury2.
Cleanse teas are laxatives with a softer name
Herbal cleanse products can include stimulant laxatives; the 2011 review lists cascara among cleanse ingredients3. Cascara, aloe and senna all belong to this group78.
The FDA has already ruled on two of them. In 1998, it asked for data on whether aloe and cascara damage genes or cause cancer. No one sent any7.
In May 2002, the agency ruled that neither herb was generally recognized as safe and effective in over-the-counter laxatives7. About 170 products had to be reformulated by that November7.
Two details matter. The rule left senna for a later decision. And it covered over-the-counter laxative drugs; it didn’t address dietary supplements7. Many cleanse products are sold as supplements, which the FDA doesn’t approve before sale3.
Senna is still sold as a laxative. Britain’s official product information for one senna tablet, a UK label revised in 2025, spells out its limits8:
- for occasional constipation, for no more than a week, and not long term;
- not for weight loss;
- prolonged, heavy use can upset fluid and electrolyte balance and drive potassium down;
- low potassium strengthens heart drugs called cardiac glycosides, and diuretics, steroids and licorice root can add to the imbalance;
- not during pregnancy or breastfeeding.
Licorice, notably, shows up in some cleanse blends3. If you take heart medicine, a water pill or a steroid, ask your pharmacist before using any laxative tea.
What about the fear that laxatives make your bowel “lazy” for good? The UK label warns that overuse can lead to dependence8. NIDDK’s view is calmer. It suggests stimulant laxatives only when constipation is severe or other treatments haven’t worked9.
If you’ve relied on laxatives for a long time, NIDDK says to talk with your doctor about tapering off. Once you stop, it says, your colon should start moving stool normally over time9.
The 2011 review also links some herbal cleanse preparations to liver toxicity3. In 2025, one gastroenterologist described a patient whose high liver enzymes returned to normal within four weeks of stopping an herbal cleanse tea6.
Salt-water flushes and juice cleanses
A salt-water flush means drinking heavily salted warm water to set off diarrhea, or sometimes vomiting. Online recipes call for 1 to 2 teaspoons of salt in a liter of water, according to doctors who reported a fatal case in the American Journal of Emergency Medicine in 202014.
Their patient was a 21-year-old woman with a history of an eating disorder. She had been purging with salt-water flushes14. She reached the hospital after vomiting and a seizure, with a dangerously high blood sodium level.
Surgery found a mass of salt in her stomach. It had led to a torn stomach and dying bowel tissue. She died two days after arriving14.
It takes less salt than most people would guess to drive blood sodium to dangerous levels, the authors warned. By their estimate, under 25 grams of table salt could kill an adult14.
If you or someone you love uses salt water, laxatives or cleanses to purge or control weight, you don’t have to handle it alone. Call the National Alliance for Eating Disorders helpline at 1-866-662-1235. If you’re in crisis or thinking about harming yourself, call or text 988. For a suspected salt overdose, call Poison Control at 1-800-222-1222, or 911 for a seizure or confusion.
Juice cleanses carry different risks, including a documented case of kidney damage after a green smoothie cleanse. Our detox and smoothie articles cover them.
Cleanse claims vs. colon facts
Medical bowel prep is the one cleanse with a clear purpose. Before certain X-rays or an endoscopic exam, a clinician has you empty your colon. That is the one use colonic machines can be cleared for4.
A wellness cleanse has no such target. This table puts common claims next to the record.
| The claim | What the evidence shows |
|---|---|
| “Your colon stores 6 to 40 pounds of old waste.” | The figure comes from a product’s marketing; doctors who look inside colons haven’t reported such buildup13 |
| “Mucoid plaque coats your colon walls.” | Not reported by pathologists or surgeons; the ropes are likely the product’s own swollen fiber13 |
| “This colonic machine is FDA cleared.” | Clearance covers only medically needed cleansing, such as before exams; no machine is approved for routine well-being use346 |
| “Colonics are gentle and natural.” | Perforations, infections, burns and electrolyte emergencies are documented123 |
| “Herbal cleanse teas are just tea.” | Cascara, aloe and senna are stimulant laxatives; aloe and cascara lost their OTC laxative status in 200278 |
| “A salt flush is a quick, safe reset.” | Small amounts of salt can be dangerous, and a fatal case has been reported14 |
A gentle seven-day reset that works with your colon
The urge to cleanse comes from a good place: wanting to feel light, clean and in charge of your own health. The colon answers best to steady habits, not a single dramatic flush.
This plan is our own, built from NIDDK’s constipation advice and the 2025–2030 Dietary Guidelines91015. It adds one change a day and keeps each one. Our fiber guides cover longer-term targets.
| Day | Focus | What to do |
|---|---|---|
| 1 | Routine | Pick a set bathroom time, such as 15 to 45 minutes after breakfast; give yourself enough time, and try a footstool9 |
| 2 | Fluids | Keep water at every meal; you’ll need more as fiber rises915 |
| 3 | Fruit | Add one high-fiber fruit, such as berries, a pear or an apple with the skin on10 |
| 4 | Whole grains | Swap one refined grain for oatmeal or whole wheat bread; the guidelines suggest 2 to 4 whole-grain servings a day1015 |
| 5 | Beans | Add a serving of lentils, black beans or chickpeas to one meal10 |
| 6 | Vegetables and movement | Add carrots, broccoli, peas or collards at two meals, and take a walk910 |
| 7 | Fermented food and review | Try sauerkraut, kefir, kimchi or miso, then note what felt better15 |
Add fiber a little at a time so your body can adjust10. Skip the laxative tea while you test the plan, so you can tell what helped.
How strong is the evidence?
| Practice | Rating | Why |
|---|---|---|
| Adding fiber gradually, with fluids, for constipation | Core advice from NIDDK, the federal digestive-disease institute910 | |
| Regular activity and a set bathroom time | NIDDK says these may help9 | |
| A layer of “mucoid plaque” exists and needs removing | Not reported by doctors who look inside colons; the ropes are likely the product13 | |
| Colonic irrigation for general health | No strong supporting studies; perforations and infections documented23 | |
| Stimulant laxative teas as a routine cleanse | A UK senna label limits use to a week; heavy use lowers potassium8 | |
| Coffee enemas | Nine reports of harm and no study showing benefit6 | |
| Salt-water flushes | Small amounts of salt can be dangerous; a fatal case is reported14 |
Questions readers ask
Is a single colonic at a spa dangerous?
Serious injuries appear to be rare, but little is known about how many colonics are done, so the true risk is unknown2. If you go, ask what the machine is cleared for and who trained the operator34. Skip it if you’re in one of the higher-risk groups above23.
Are herbal detox teas safe because they’re natural?
Not automatically. The FDA pulled aloe and cascara from over-the-counter laxatives for lack of safety data, and a British senna label caps use at a week78. Read the ingredient list, and ask your pharmacist if you take heart medicine, diuretics or steroids8.
Will a cleanse help me lose weight?
The British senna label says plainly that stimulant laxatives don’t help with weight loss, and notes that dehydration can look like weight loss8. Our detox article explains why quick cleanse losses tend to return.
I feel backed up and bloated. What should I try first?
Start with NIDDK’s basics: add fiber gradually, drink fluids, move more and keep a regular bathroom routine910. If self-care doesn’t help, or you notice any warning signs, see a clinician11.
The bottom line
Your colon doesn’t need scraping. The dramatic claims behind cleanses, from pounds of hidden waste to mucoid plaque, haven’t held up. The tools used to chase them carry documented risks: perforations and infections from colonics, potassium loss from laxative teas and fatal sodium levels from salt flushes.
The one legitimate clean-out is the medical bowel prep your clinician prescribes before an exam. For everyday comfort, the steps with the best support are slower and kinder: fiber added gradually, fluids, movement and a steady routine. Give those a week, and keep the ones that work.
Related reading
About this article
This article was researched using CDC and FDA records, federal regulations, NIH guidance, a Canadian public health review, peer-reviewed case reports and medical journal coverage, all listed below. It was reviewed in October 2026. It is general education, not medical, legal or financial advice.
Sources
- Centers for Disease Control and Prevention. “Amebiasis Associated with Colonic Irrigation — Colorado.” Morbidity and Mortality Weekly Report, March 13, 1981 (CDC Stacks). stacks.cdc.gov
- Eykelbosh A, Wiens M. “Adverse Effects After Medical, Commercial, or Self-Administered Colon Cleansing Procedures.” National Collaborating Centre for Environmental Health, BC Centre for Disease Control, January 2018. ncceh.ca
- Jones AA, Mishori R, Otubu A. “The Dangers of Colon Cleansing.” Journal of Family Practice, 2011 (MDedge). mdedge.com
- Electronic Code of Federal Regulations. 21 CFR 876.5220, “Colonic Irrigation System” (Cornell Legal Information Institute copy), accessed October 2026. law.cornell.edu
- U.S. Food and Drug Administration, Dallas District. Warning Letter 97-DAL-WL-24 to Tiller Mind and Body, Inc., San Antonio, Texas, June 2, 1997 (archived copy of the FDA letter, hosted by Quackwatch; no FDA-hosted copy located). quackwatch.org
- Doheny K. “Colon Cleanses: How to Discourage Patients.” GI & Hepatology News (MDedge), November 4, 2025. mdedge.com
- U.S. Food and Drug Administration. “Status of Certain Additional Over-the-Counter Drug Category II and III Active Ingredients.” Final rule, Federal Register 67 FR 31125, May 9, 2002. govinfo.gov
- Electronic Medicines Compendium (UK). “Senokot 7.5 mg Tablets Adult: Summary of Product Characteristics.” Revised May 2025. medicines.org.uk
- National Institute of Diabetes and Digestive and Kidney Diseases. “Treatment for Constipation.” NIH, last reviewed May 2018. niddk.nih.gov
- National Institute of Diabetes and Digestive and Kidney Diseases. “Eating, Diet, & Nutrition for Constipation.” NIH, last reviewed May 2018. niddk.nih.gov
- National Institute of Diabetes and Digestive and Kidney Diseases. “Symptoms & Causes of Constipation.” NIH, last reviewed May 2018. niddk.nih.gov
- National Institute of Diabetes and Digestive and Kidney Diseases. “Symptoms & Causes of Diarrhea.” NIH, last reviewed September 2024. niddk.nih.gov
- Schwarcz J. “You’re Full of Crap. Literally.” McGill University Office for Science and Society, September 2018. mcgill.ca
- Hancher J, Fisher J, Shenvi C. “Severe Hypernatremia and Gastric Dilation From Chronic Eating Disorder and Intentional Salt Ingestion.” American Journal of Emergency Medicine, 2020. ajemjournal.com
- U.S. Department of Agriculture and U.S. Department of Health and Human Services. “Dietary Guidelines for Americans, 2025–2030.” January 2026. cdn.realfood.gov