Activated charcoal
Activated charcoal has one proven job: it is given by clinicians to bind a swallowed poison in the gut, and it works best in the first hour. The main caution is that it binds other medicines in the gut, so it should be kept well apart from anything you take by mouth.
For wind and bloating the one controlled trial we found showed no benefit, and for hangovers, 'detox' and teeth whitening there is no good evidence, with reviews finding charcoal toothpaste abrasive and less effective than alternatives.
At a glance
Last reviewed 10 October 2026What it's used for
Evidence is rated per use. The same ingredient can be strong for one thing and traditional for another.
| Use | Evidence | What the research shows |
|---|---|---|
| Poisoning and overdose (given by clinicians) | Moderate | Volunteer studies using at least 50 g found charcoal cut drug absorption by about 47% when given 30 minutes after dosing and about 21% at 3 hours, but the toxicology position paper found no well-designed clinical study showing better patient outcomes and says it should not be given routinely. A 2021 systematic review of 296 human studies rated 83% of the evidence low or very low quality, with moderate or high quality data for a few drugs such as paracetamol, digoxin and theophylline, and reported benefit beyond one hour in many scenarios. This is a hospital treatment; poison centres say not to treat poisoning with it at home.1,2,3 |
| Wind, gas and bloatingCompare remedies for digestion → | Limited | In a double-blind trial of 34 people with gas-related symptoms, charcoal 400 mg twice a day for 7 days did not reduce hydrogen production or overall symptom severity, while the antibiotic rifaximin did. That is one small trial with no placebo arm, so it is a reason for doubt rather than proof of no effect.5 |
| 'Detox', hangover and general cleansing | Traditional | We found no controlled human trial of charcoal supplements for detoxification, hangovers or general wellbeing. Its binding action is real in the gut after a swallowed poison, but that does not show that a daily tablet clears toxins from the body. Poison Control notes that over-the-counter products lack the potency of medical-grade charcoal.3 |
| Teeth whitening (toothpaste or powder) | Traditional | A 2023 systematic review of 11 laboratory and human studies found charcoal toothpastes whiten less than other options and have higher abrasive potential, so they may be less safe for enamel. A 2017 JADA review found insufficient clinical and laboratory data to back safety or efficacy claims, and the American Dental Association says there is insufficient evidence of measurable whitening benefit with adequate safety.6,7,8 |
How much
Ranges below are what studies used and what supplements commonly contain. They are not a recommendation for you. Start at the low end.
How people take it
Safety
Who should avoid
- Bleeding in the gut, a bowel perforation or a bowel blockage — do not take it
- Drowsy people or an unprotected airway — risk of breathing it in
- Anyone on regular medicines — charcoal can stop them being absorbed
- Suspected poisoning — call a poison centre or emergency service, not charcoal at home
- Caustic products or hydrocarbons — charcoal is not used, due to aspiration and vomiting risks
Known interactions
Questions people ask
What are the benefits of activated charcoal?
The proven one is treating some swallowed poisons and overdoses in hospital, best within an hour. For wind, bloating, hangovers and detox we found no good evidence, and the one bloating trial found no effect.
What are the side effects of activated charcoal?
Black stools are expected, and constipation and vomiting can occur, especially when large amounts are taken quickly. It should not be used with gut bleeding, perforation or blockage, and breathing it in is a risk if you are drowsy.
Does activated charcoal whiten teeth?
Not reliably. A 2023 systematic review found charcoal toothpastes whiten less than other products and are more abrasive, and the American Dental Association says there is insufficient evidence of safe, measurable whitening.
How do I use or make activated charcoal at home?
We found no sourced home use or recipe we can support. Poison Control says not to treat a poisoning with it at home, and shop products are much weaker than hospital doses. Take medicines at least 2 hours away from any charcoal.
Sources (9)
- Position statement Chyka PA, Seger D, Krenzelok EP, Vale JA. Position paper: Single-dose activated charcoal. Clin Toxicol (Phila). 2005.
- Systematic review Hoegberg LCG, Shepherd G, Wood DM, et al. Systematic review on the use of activated charcoal for gastrointestinal decontamination following acute oral overdose. Clin Toxicol (Phila). 2021.
- Poison centre America's Poison Centers. Activated charcoal: An effective treatment for poisonings.
- Clinical guideline Médecins Sans Frontières. Activated charcoal (oral). Essential drugs.
- Randomised trial Di Stefano M, Strocchi A, Malservisi S, et al. Non-absorbable antibiotics for managing intestinal gas production and gas-related symptoms. Aliment Pharmacol Ther. 2000.
- Systematic review Tomás DBM, Pecci-Lloret MP, Guerrero-Gironés J. Effectiveness and abrasiveness of activated charcoal as a whitening agent: A systematic review of in vitro studies. Ann Anat. 2023.
- Literature review Brooks JK, Bashirelahi N, Reynolds MA. Charcoal and charcoal-based dentifrices: A literature review. J Am Dent Assoc. 2017.
- Professional body American Dental Association. Whitening.
- Clinical study Elomaa K, Ranta S, Tuominen J, Lähteenmäki P. Charcoal treatment and risk of escape ovulation in oral contraceptive users. Hum Reprod. 2001.
Last reviewed 10 October 2026 · Next review April 2027 · How we rate evidence
Reader notes
Experiences and questions from readers, read by an editor before they appear. They are personal accounts, not evidence, and are not medical advice.