Educational information, not medical advice — ask your doctor or midwife.
Smooth sumach is a tall shrub that grows across much of North America. Its bark, root bark and red berries were used as folk medicine. It is also called Pennsylvania sumach.
It is not poison sumac. Poison sumac is a different plant with white or cream berries. Red-berried sumachs like this one do not cause that blistering rash in most people.
Folk and Eclectic healers treated it as an astringent. That means a plant that dries and tightens tissue. They used bark gargles for sore throats and berry drinks for thirst and fever.
Human evidence is very thin. Almost nothing about this plant has been tested in proper trials. Long traditional use is not proof that it works, and not proof that it is safe.
The main idea behind its use is tannins. Tannins are plant compounds with a dry, puckering taste. In test tubes, they bind proteins and tighten the surface of tissue.
That binding is the likely reason a gargle feels drying in the mouth. It is also the old reasoning for using it in loose stools. Whether it helps the gut in people has not been tested well.
In laboratory tests, sumach extracts slow the growth of some bacteria. Whether this happens in a real mouth or gut is not established.
Animal and cell studies of sumach plants hint at lower blood sugar. No good human trials back this for Rhus glabra. Treat the blood sugar claim as unproven.
Smooth sumach is sold mostly as a dried herb or a liquid extract.
Common forms include:
- Whole or ground dried berries, used like a tart spice - A cold-water berry drink, sometimes called sumac lemonade - Cut and dried bark or root bark, made into gargles and washes - Tinctures, which are alcohol extracts of bark or berries - Capsules of powdered berry
The spice sold as sumac in food shops is usually Rhus coriaria. That is a related Middle Eastern plant, not this one.
Wild picking carries real risk. Only people who can tell the species apart should gather it.
Several Native American nations used smooth sumach long before settlers did. Records describe berry drinks for thirst and fever. Bark was used in washes and gargles.
Eclectic doctors in the United States listed it through the 1800s. King's American Dispensatory described bark gargles for sore mouth and throat. It was also written up for loose bowels.
Use faded as modern medicines arrived. Today it survives mainly as a tart spice and a minor folk remedy.
Stop and get medical help the same day if you get a spreading rash, or swelling of the lips, tongue or throat, or trouble breathing.
See a doctor if diarrhoea lasts more than two days, or if there is blood in your stool.
Also see a doctor for a sore throat with high fever, or one that lasts beyond a week. Yellow skin or eyes, dark urine or bad stomach pain mean stop at once and seek care.
In the United States it is sold as a dietary supplement and as a food spice, not as an approved medicine. In the UK and EU it is sold as a food or herbal product, with no approved medical claims.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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