Sumac

If you spend time outdoors, chances are you have been bothered by poison ivy, poison oak or poison sumac at some point. Most people are sensitive to the plants' oily sap. The sap is in the root, stems, leaves and fruit of these plants. If it gets on your skin, it causes a blistering skin rash. The rash can range from mild to severe, depending on how much sap gets on your skin and how sensitive you are to it. Problems can also happen if the plants are burned. Airborne sap-coated soot can get into the eyes, nose, throat and respiratory system.

The best way to avoid the rash is to learn what the plants look like and stay away from them. If you come into contact with the plants, wash your skin and clothing right away. If you develop a rash, ask your pharmacist about over-the-counter medicines. For severe rashes, see your doctor.

National Park Service

WARNING: All medicines, drugs, plants, chemicals or medicial precedures below are for historical reference only. Many of these treatments are now known to be harmful and possibly fatal. Do not consume any plant, chemical, drug or otherwise without first consulting a licensed physician that practices medine in the appropriate field.

Physician's Materia Medica on Sumac

RHUS AROMATICA (Fragrant Sumac)
The bark of the root of RHUS AROMATICA, Ait. Astringent. stimulant to non-striated muscular tissue. Used especially in nocturnal incontinence of urine.¹

SUMAC^RHUS
The bark, also the fruit of RHUS GLABRA, Lin. The bark is astringent and antiseptic; useful in passive fluxes. The fruit is astringent, acidulous, refrigerant and diuretic; especially useful as a gargle in pharyngitis.¹

References

1) Nelson, Baker & Co., 1904, Physician's Handy Book of Materia Medica and Therapeustics, Detroit, Michigan.