American White Water Lily Drug Interactions, Uses, Safety & More

American white water lily (Nymphaea odorata) is an aquatic plant native to North America. It has fragrant white flowers and large, round leaves that float on the surface of ponds, lakes, and slow-moving streams.

In traditional and folk medicine, the underground stem (rhizome) and root have been used most often. People historically used it as a gargle for throat and mouth problems, as a wash for vaginal irritation, and as a poultice placed on the skin for burns, sores, and boils. Today it is sold as a dried herb, powder, tea, or liquid extract, though it is far less common than many other herbal products.

Most uses of American white water lily come from traditional practice, not from strong scientific studies. The plant root is rich in tannins, which act as astringents — they can tighten tissue and may have a mild drying, antiseptic-like effect. This is why it was historically used in gargles, skin poultices, and vaginal washes.

There is very little modern human research on the plant. Some laboratory studies have looked at individual compounds found in it, such as the flavonoid afzelin, for possible effects on cancer cells. These are early test-tube findings only and do not show that the plant treats or prevents any disease in people.

Overall, the evidence for any specific health benefit is considered insufficient. It may be reasonable to think of it as a traditional remedy, but you should not rely on it in place of proven medical treatment.

The root contains tannins, which give it astringent and mildly antiseptic qualities. Astringents can cause proteins in surface tissue to contract, which may soothe irritated skin or mucous membranes and reduce minor weeping or discharge.

The plant also contains other natural compounds, including flavonols such as afzelin and myricitrin, along with mucilage (a slippery, soothing substance), starch, gum, resin, and small amounts of alkaloids and gallic acid. Laboratory studies have explored some of these compounds for possible antioxidant or anticancer activity.

It is important to know that most of this information comes from chemical analysis, test-tube work, or animal research. These findings do not prove that the whole plant works the same way in the human body.

There is not much modern safety information about American white water lily. Its long history of topical use suggests external use is generally well tolerated, but swallowing concentrated extracts or large amounts has not been well studied.

Because the root is high in tannins, taking a lot by mouth could cause stomach upset or nausea. People with sensitive skin should test a small area before using a poultice or wash.

Pregnant and breastfeeding people should avoid it, because there is no reliable data showing it is safe. Children, older adults, and people with chronic medical conditions should also check with a healthcare professional first. As with any wildcrafted plant, there is a risk of contamination or misidentification, so only use products from a reputable source.

Reported side effects are not well documented because the plant has not been formally studied. Based on its tannin content, possible effects include stomach upset, nausea, or constipation if large amounts are swallowed.

Topical use may rarely cause skin irritation or an allergic reaction. Stop using it and seek medical care if you notice a rash, swelling, trouble breathing, or other signs of an allergic reaction.

There is no established standard dose for American white water lily. Traditional use involved preparing the root as a tea, wash, gargle, or poultice, but exact amounts were not standardized and varied widely.

If you choose to use a commercial product, follow the directions on the label and do not exceed them. Because reliable dosing guidance is lacking, it is best to check with a pharmacist or doctor before use, especially if you plan to take it by mouth.