Tannic Acid Drug Interactions, Uses, Effectiveness, Safety & More
What is this page for?
First and foremost: how Tannic Acid interacts with medications. The heart of this page is the interaction list — every drug Tannic Acid is known to interact with, and how serious each one is.
But these pages have grown well beyond that into a full monograph — what Tannic Acid is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy
Check Tannic Acid against your medication
Add one medicationDrugs that interact with Tannic Acid
0 medications have a known interaction with Tannic Acid, graded by severity. Select any drug for the full evidence-based detail.
We don’t currently list any known drug interactions for Tannic Acid. This doesn’t guarantee none exist — always confirm with your pharmacist before combining supplements with your medications.
What Severity, Likelihood & Evidence Mean
Severity — How Serious It Can Be
- Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
- Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
- Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
- No known interaction. Checked against our sources with nothing documented — not the same as proven safety.
Likelihood — How Well It’s Documented
- Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
- Probable. Interaction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
- Possible. Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
- Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Where This Data Comes From
- Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
- Each drug listed above links to the full report for that exact Tannic Acid combination — clinical detail, likelihood, evidence level, and citations.
- Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
Tannic Acid: Uses, Safety & Side Effects
Tannic acid is a plant-derived astringent used mostly on the skin and in the mouth to dry out and tighten tissue. There is some traditional and topical use, but high-quality evidence for most uses is limited, and it can be harmful if too much is absorbed, especially on broken skin or burns.
- Part used
- Tannins extracted from plant sources such as oak galls, bark, and certain seeds and leaves
- Common forms
- Topical powders and solutions, throat lozenges, gargles, suppositories, and some over-the-counter skin products
- Minor skin irritation and weeping rashes
- Sore throat and mouth sores
- Minor burns and blisters
- Astringent for skin
- Hemorrhoids
Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.
Generally used topically in small amounts, but absorption through broken skin or large burns can harm the liver.
When used topically on damaged or broken skin. There is insufficient reliable information available about the safety of tannic acid when used orally d...
Read the full pregnancy detailWhen used topically on damaged or broken skin. There is insufficient reliable information available about the safety of tannic acid when used orally d...
Read the full breastfeeding detailPregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Overview
Tannic acid is a type of natural compound called a tannin. Tannins are found in many plants, including oak galls, tree bark, tea leaves, and certain fruits and seeds. They give some plants and beverages, like strong tea or red wine, their dry, puckery taste.
People have used tannic acid for a long time as an astringent, meaning it tightens and dries tissue. You may find it in some topical skin products, throat lozenges, gargles, and treatments for minor skin problems. In the past, it was even used on burns, though that practice has largely been stopped because of safety concerns.
How it works
Tannic acid works mainly as an astringent. It binds to proteins on the surface of skin and mucous membranes, causing them to tighten and become firmer. This can reduce oozing and create a temporary protective layer.
In laboratory studies, tannins have shown antimicrobial and antioxidant activity, and they can bind to certain compounds. However, many of these effects come from test-tube or animal research and may not translate directly into proven benefits in people.
Does Tannic Acid work?
How to read these evidence grades
Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.
Possibly Ineffective Burns
Applying tannic acid doesn't seem to be effective for treating minor burn or sunburn.
Possibly Ineffective Diaper rash
Applying tannic acid doesn't seem to be effective for treating diaper rash.
Possibly Ineffective Herpes labialis (cold sores)
Applying tannic acid doesn't seem to be effective for treating cold sores and fever blisters.
Possibly Ineffective Prickly heat
Applying tannic acid doesn't seem to be effective for treating prickly heat.
Also studied for 3 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Diarrhea
Research on the use of gelatin tannate (tannic acid suspended in a gelatin solution) for the treatment of diarrhea due to acute gastroenteritis is conflicting. A small clinical study in children 3 months to 6 years of age with acute gastroenteritis shows that taking gelatin tannate 250-500 mg four times daily for 5 days in combination with oral rehydration solution (ORS), starting within 3 days of symptom presentation, reduces the number of bowel movements at 72 hours and reduces the duration of diarrhea by about 31 hours when compared with ORS alone. However, another small clinical study in children younger than 5 years old with acute gastroenteritis shows that taking this same dose of gelatin tannate along with ORS, starting within 5 days of symptom presentation, does not affect the number of daily watery stools or duration of diarrhea when compared with placebo and ORS. The difference in these findings might be due to the duration of symptoms at the time of treatment initiation, severity of diarrhea, or the use of a placebo control.
Insufficient Reliable Evidence To Rate Hyperhidrosis
A small preliminary clinical study in patients with palmar-plantar hyperhidrosis shows that applying tannic acid 20% lotion to one palm nightly is less effective for reducing symptoms of hyperhidrosis than once weekly iontophoresis with a glycopyrronium bromide 1% medium.
Insufficient Reliable Evidence To Rate Osteoarthritis
Some clinical research in patients with knee osteoarthritis shows that applying a specific cream containing tannic acid, comfrey extract, aloe vera gel, eucalyptus oil, and frankincense oil (4Jointz, Arthritis Relief Plus Ltd) about 3.5 grams three times daily for 6-12 weeks decreases pain and stiffness and improves physical function when compared with placebo. It is not clear if this effect is due to tannic acid, the other ingredients, or the combination.
Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.
Safety & precautions
When used in small amounts on small areas of intact skin or as a gargle, tannic acid is usually well tolerated. The bigger concern is when it is applied to broken skin, open wounds, or large burns, because more of it can be absorbed into the body. Significant absorption has been linked to liver damage, which is one reason it is no longer used on burns.
People with liver problems, sensitive skin, or large areas of damaged skin should be especially careful. Avoid swallowing large amounts.
For pregnancy and breastfeeding, there is not enough reliable safety information. To be safe, avoid using tannic acid during these times unless your doctor or pharmacist specifically recommends it.
Side effects
The most common side effects from topical use are local skin irritation, dryness, redness, or stinging at the site of application. Some people may have an allergic reaction.
Used in the mouth, it can cause a dry, puckery feeling. Swallowing large amounts may upset the stomach. The most serious, though rare, risk is liver injury when large amounts are absorbed through broken skin or burns.
Tannic Acid: Reported Adverse Effects
Documented safety reports on Tannic Acid from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.
Orally, large amounts of tannic acid can cause gastric irritation, nausea, and vomiting. Extensive use of tannins on burns or in enemas has been associated with fatal liver damage. However, this toxicity may be due to digallic acid, an impurity that is sometimes found in tannic acid.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
Burns Hepatic
Extensive use of tannins on burns or in enemas has been associated with fatal liver damage. However, this toxicity may be due to digallic acid, an impurity that is sometimes found in tannic acid.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
Nausea and vomiting Gastrointestinal
Orally, large amounts of tannic acid can cause gastric irritation, nausea, and vomiting.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
Adverse-effects data: Natural Medicines, Therapeutic Research Center
Dosing
There is no well-established standard dose of tannic acid for supplement use. The amount varies widely depending on the product and how it is used (for example, a skin solution versus a lozenge).
The safest approach is to follow the directions on the product label and not apply it to large areas of broken or burned skin. If you are unsure how to use a product or how much is appropriate, ask your pharmacist or doctor before using it.
Tannic Acid & Pregnancy
Tannic Acid & Breastfeeding
© 2026 Therapeutic Research Center
Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center
References & further reading
The 8 references that drive our Tannic Acid monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.
- Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
- Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
- Laslett, L. L., Quinn, S. J., Darian-Smith, E., Kwok, M., Fedorova, T., Korner, H., Steels, E., March, L., and Jones, G. Treatment with 4Jointz reduces knee pain over 12 weeks of treatment in patients with clinical knee osteoarthritis: a randomised contr
- Smith DB, Jacobson BH. Effect of a blend of comfrey root extract (Symphytum officinale L.) and tannic acid creams in the treatment of osteoarthritis of the knee: randomized, placebo-controlled, double-blind, multiclinical trials. J Chiropr Med. 2011;10(3) PubMed
- Goh CL, Yoyong K. A comparison of topical tannic acid versus iontophoresis in the medical treatment of palmar hyperhidrosis. Singapore Med J. 1996;37(5):466-8.
- Kołodziej M, Bebenek D, Konarska Z, Szajewska H. Gelatine tannate in the management of acute gastroenteritis in children: a randomised controlled trial. BMJ Open. 2018;8(5):e020205. PubMed
- Mennini M, Tolone C, Frassanito A, Midulla F, Cucchiara S, Aloi M. Gelatin tannate for acute childhood gastroenteritis: a randomized, single-blind controlled trial. Paediatr Drugs. 2017 Apr;19(2):131-137. PubMed
This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.
Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Tannic Acid: Common Questions
What is Tannic Acid used for, and does it work?
Does Tannic Acid interact with prescription medications?
How are Tannic Acid interactions rated?
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Where does this Tannic Acid interaction information come from?
What is Tannic Acid used for?
Is Tannic Acid safe?
Can I use Tannic Acid during pregnancy or breastfeeding?
Why isn't Tannic Acid used on burns anymore?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
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