American Chestnut Drug Interactions, Uses, Effectiveness, Safety & More
What is this page for?
First and foremost: how American Chestnut interacts with medications. The heart of this page is the interaction list — every drug American Chestnut is known to interact with, and how serious each one is.
But these pages have grown well beyond that into a full monograph — what American Chestnut 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 American Chestnut against your medication
Add one medicationDrugs that interact with American Chestnut
0 medications have a known interaction with American Chestnut, graded by severity. Select any drug for the full evidence-based detail.
We don’t currently list any known drug interactions for American Chestnut. 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 American Chestnut combination — clinical detail, likelihood, evidence level, and citations.
- Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
American Chestnut: Uses, Safety & Side Effects
American chestnut leaves and bark have a long history of folk use for coughs and respiratory complaints, mainly because of their tannin content, which has an astringent effect. However, there is very little modern scientific evidence to support these uses, and safety has not been well studied, so it should be used cautiously and discussed with a healthcare professional.
- Scientific name
- Castanea dentata
- Family
- Fagaceae
- Part used
- Leaves and bark
- Common forms
- Tea, liquid extract, dried leaf
- Cough and whooping cough
- Respiratory ailments
- Sore throat (topical/gargle)
- Astringent for mucous membranes
- Traditional tonic and sedative
Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.
Little modern safety data exists, and the high tannin content can irritate the stomach or affect nutrient absorption.
Insufficient reliable information available; avoid using.
Read the full pregnancy detailInsufficient reliable information available; avoid using.
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
The American chestnut (Castanea dentata) is a large deciduous tree that was once one of the most common trees in the forests of the eastern United States. In the early 1900s, a fungal disease called chestnut blight spread from imported Asian trees and wiped out most of the mature American chestnuts. Today, scientists are working to breed blight-resistant trees to bring the species back.
In traditional and folk medicine, the leaves and bark of the tree have been used to make teas and extracts. People have taken these preparations by mouth for coughs and respiratory problems, and used them as gargles for sore throats. The leaves and bark are rich in tannins, which give them an astringent (tissue-tightening) quality.
How it works
The main active compounds in American chestnut leaves and bark are tannins. Tannins are plant chemicals that bind to proteins and can tighten and dry tissues, which is why they are called astringents. When applied to mucous membranes, tannins may form a protective layer, reduce secretions, and create a soothing effect.
This astringent action is the proposed reason the plant was used for sore throats, coughs, and minor irritation. Keep in mind that these explanations are based mostly on the known behavior of tannins and on laboratory observations, not on well-designed human studies of American chestnut itself.
Does American Chestnut work?
How to read these evidence grades
Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.
For American Chestnut, current evidence isn’t strong enough to rate any specific use. The conditions it has been studied for are listed below.
Also studied for 2 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Cough
Although there has been interest in using oral American chestnut for cough, there is insufficient reliable information about the clinical effects of American chestnut for this purpose.
Insufficient Reliable Evidence To Rate Pharyngitis
Although there has been interest in using topical American chestnut for pharyngitis, there is insufficient reliable information about the clinical effects of American chestnut for this purpose.
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
There is not much modern safety information on American chestnut as a medicine. Because the leaves and bark are high in tannins, large amounts taken by mouth may irritate the stomach and can interfere with the absorption of certain nutrients, minerals, and proteins.
People with stomach or digestive problems, those with iron-deficiency or absorption concerns, and anyone with liver problems should be especially cautious. Pregnant and breastfeeding women should avoid American chestnut because its safety has not been studied in these groups. Children should not be given it without medical advice. Always talk with a pharmacist or doctor before using it.
Side effects
Because formal studies are lacking, the full side-effect profile is unknown. Based on its high tannin content, possible effects include stomach upset, nausea, or constipation, especially with larger or frequent doses.
Tannin-rich plants taken in large amounts over a long time have been linked to digestive irritation and reduced absorption of iron and other nutrients. Allergic reactions are also possible. Stop using it and seek medical care if you notice signs of an allergic reaction such as rash, swelling, or trouble breathing.
Dosing
There is no standardized or well-established dose for American chestnut. Traditional use involved teas or extracts made from the dried leaves, but the amount of active compounds can vary widely depending on the product and how it is prepared.
If you choose to use a product, follow the directions on the label and do not exceed them. Because reliable dosing information is missing, it is wise to check with a pharmacist or doctor before starting, and to avoid long-term or high-dose use.
American Chestnut & Pregnancy
American Chestnut & Breastfeeding
© 2026 Therapeutic Research Center
Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center
References & further reading
The 2 sources that drive our American Chestnut monograph — publicly available pages from reputable medical and government organizations. Every link was verified to work before publishing.
Keep readingThis 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.
Brands that make products with American Chestnut
1 brand in our database make a supplement containing American Chestnut.
Supplement products with American Chestnut
4 products in our database contain American Chestnut. Open any to see its full ingredient list and every drug interaction we check.
American Chestnut: Common Questions
What is American Chestnut used for, and does it work?
Does American Chestnut interact with prescription medications?
How are American Chestnut interactions rated?
Is it safe to take American Chestnut with my medications?
Where does this American Chestnut interaction information come from?
What is American Chestnut used for?
Is American Chestnut safe to take?
Can I use American Chestnut if I'm pregnant or breastfeeding?
Is American Chestnut the same as the nuts people eat at the holidays?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Products that contain American Chestnut
A rotating sample of real supplements in our database that list American Chestnut — open any to see its full ingredients and every drug interaction we check.
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