Stinging nettle tea is a folk remedy for illnesses such as joint pain and water retention. These days, the herbal tea enjoys continued respect from the alternative medicine community. Nettle root tea may lower men's risk of benign prostatic hyperplasia, while nettle leaf tea is studied for its potential to treat osteoarthritis, high blood pressure and diabetes. You may be concerned, however, that stinging nettle tea is painful to drink or that it will provoke dangerous side effects.
In his book “Identifying and Harvesting Edible and Medicinal Plants,” wild foods author Steve Brill reports that amateur foragers in his education groups are wary about ingesting stinging nettle because the plants are notoriously painful when accidentally touched. Euell Gibbons, the well-known advocate of wild plant foraging, once wrote that nettle “weeds” are so feared and reviled for their invasive qualities and their stinging plant parts, that few people realize nettles make useful -- and painless -- tea and food when prepared properly. Boiling, drying, infusing or steaming removes the stingers from nettles within seconds.
Potential side effects from stinging nettle tea include mild indigestion. Despite the fact that stinging nettle is a mild diuretic, in some cases the tea reportedly caused water retention. If you prepare your own nettle leaf or root tea, being stung during the harvesting and drying processes represents another obvious hazard. University of Maryland Medical Center (UMMC) notes, however, that the herbal tea is generally considered safe for most people.
Drug interactions with stinging nettle tea are considered unlikely, according New York University’s Langone Medical Center. Stinging nettle’s potential to lower blood pressure is generally considered a positive aspect of the herb. But UMMC warns that if you are taking prescription medication for high blood pressure, stinging nettle tea may dangerously increase the prescription medication’s strength. Similarly, the herb’s ability to lower blood sugar or thin the blood may dangerously magnify diabetes or blood-thinning medications. For people taking prescription diuretics, the diuretic action of stinging nettle tea may prove too strong a combination and provoke dehydration in some people. While the NYU Langone Medical Center echoes these warnings, the institution notes that the risks are “theoretical” and that no known drug interactions are on record.
According to Brill, tea made from late-season nettle leaves may contain compounds harmful to the kidneys; gather leaves before they flower. UMMC warns pregnant women to avoid nettle tea because it can potentially cause miscarriage. However, as with many herbal medications for pregnant women, the warning is the subject of some debate. The American Pregnancy Association, while noting nettle tea’s rating as “likely unsafe” from the Natural Medicines Database, suggests that women ask their obstetrician before ruling nettle tea in or out of your diet. Some herbalists and midwives recommend the mineral-rich tea to bolster health during pregnancy.