Educational information, not medical advice — ask your doctor or midwife.
Sumach is the bark, root bark and red berry cluster of Rhus glabra, a shrub native to North America. Folk and Eclectic healers used it as an astringent, a drying, puckering remedy for sore throats, mouth sores and loose bowels.
The ripe berries are tart and hairy with acid. They were soaked in cool water to make a tangy pink drink. The bark and root bark were simmered into gargles and skin washes.
It is also called smooth sumach, upland sumach and Pennsylvania sumach. It is not the same plant as the red cooking spice sold as sumac, which is usually Rhus coriaria.
Here is the honest verdict. There are no good human trials of Rhus glabra for any health use. Its traditional standing is long and well recorded, but tradition is not proof that it works or that it is safe.
The proposed action is astringent. Tannins bind to proteins in the surface layer of tissue, which can make a raw throat or gum feel tighter and less weepy.
That binding is well shown in test tubes. Whether it eases a real sore throat or shortens diarrhoea in people has not been tested properly.
In laboratory tests, Rhus glabra extracts slow the growth of some bacteria and mop up free radicals. These are dish studies. They do not show that drinking a sumach tea does the same thing in your body.
Some animal and cell work on related sumach species points to effects on blood sugar and blood fats. That work is early, it is mostly not on Rhus glabra, and it should not be read as a result in people.
Sumach is sold and used in a few plain forms.
- Dried berry clusters, steeped in cool or cold water as a tart drink.
- Loose dried bark or root bark for a simmered tea, often used as a gargle.
- Liquid extracts and tinctures, a legacy of Eclectic pharmacy.
- Powdered bark, sometimes found in old mouthwash and tooth powder recipes.
For comparison, the red kitchen spice labelled sumac is a different species, Rhus coriaria. Reading the Latin name on the label is the only reliable check.
Several Native American nations used smooth sumach long before settlers recorded it. Reported uses included berry drinks for fever and thirst, bark washes for sores, and root preparations for mouth and throat complaints.
Nineteenth-century Eclectic doctors took it up. King's American Dispensatory listed Rhus glabra as an astringent for sore throat, spongy gums, mouth ulcers and chronic looseness of the bowels.
It was also used as a gargle after scarlet fever and as a wash for old wounds. These were the accepted practices of the day, written down before controlled trials existed.
The remedy faded from medical use in the early twentieth century. It survives today mainly as a foraged drink and a folk gargle.
Stop using it and see a doctor if any of these happen.
- You get a rash, itching, or swelling of the lips, tongue or face. - You have trouble breathing or a tight throat. Call emergency services. - A sore throat comes with a high fever, pus on the tonsils, or lasts more than three days. - Diarrhoea lasts more than two days, or you see blood. - You feel faint, pass little urine, or cannot keep fluids down. - You get ongoing stomach pain, vomiting or dark stools.
In the United States, Rhus glabra is sold as a food item or a dietary supplement, not as an approved medicine. In the UK and the EU, it is not an authorised herbal medicine, and no product may claim to treat disease.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
Reviewed by the HealisticMD editorial team How we grade evidence →
The published evidence for Sumach is weak or absent. That usually means no controlled trial has tested it, not that a trial found it ineffective — the two are different, and we grade only what has been published.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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