Utpala (Nymphaea stellata): Benefits, Evidence, Dosage & Safety

TL;DR

Utpala is the flower of the blue water lily (Nymphaea stellata), used in Ayurveda for burning thirst, bleeding disorders, vomiting and painful urination at 3–6 g of flower. Animal studies report blood-sugar lowering, liver protection and anti-inflammatory effects; a sterol, nymphayol, raised insulin in diabetic rats. No human trials exist, so none of these effects are established in people.

(60 words. Sources: Raja et al. 2010 comprehensive review, J Adv Pharm Technol Res, PMC3255414; Ayurvedic Pharmacopoeia of India via the same review.)

What it is

Utpala is the Sanskrit name for the dried flowers of Nymphaea stellata Willd. (synonym Nymphaea nouchali Burm.f.), the Indian blue water lily of the family Nymphaeaceae (Raja et al., 2010). The Ayurvedic Pharmacopoeia of India has a monograph specifying identity, purity and strength parameters for the flowers of N. stellata (foreign matter, ash values, extractive values, TLC pattern) (same review). Botanists note considerable synonymy confusion around this species: N. stellata and N. nouchali are treated as synonyms in the review, though some floras separate them (same review). It is not a true lotus (Nelumbo nucifera), despite sometimes being called "blue lotus."

Traditional use

In Ayurveda and Siddha, N. stellata is used as a single drug and as an ingredient of classical formulations including Asokarista, Arvindasava, Usirasava, Candanasava, Kalyanaka Ghrta, Samangadi Curna and Triphala Ghrta (Raja et al., 2010). The review's compilation of traditional uses records 3–6 g of the dried flower for burning thirst (pipasa daha), bleeding disorders (raktapitta), vomiting, fainting, heart disease, painful or difficult urination and diarrhea with fever. The powdered rootstock for dyspepsia, diarrhea and piles; the roots as an emollient and diuretic; and the flowers and roots as mildly sedative (same review). Charaka (Sutrasthana 27/115) groups water lilies among the astringent, bleeding-disorder-alleviating substances (Raja et al., 2010). These are traditional claims, not clinical proof.

What modern research says

No human clinical trials of Nymphaea stellata were found. The review authors themselves note that, given the scale of its traditional use, the experimental studies conducted are "still negligible" (Raja et al., 2010). All findings below are from animal or test-tube studies.

Blood sugar and lipids

An ethanolic leaf extract (100 and 200 mg/kg) significantly and dose-dependently reduced hyperglycemia in alloxan-induced diabetic rats and lowered the elevated cholesterol and triglycerides, with no effect in normal rats. A hydroalcoholic flower extract (200–400 mg/kg) showed significant antihyperglycemic activity on oral glucose tolerance testing, with 300 mg/kg reducing blood glucose by about 45% four hours after dosing (animal studies) (Raja et al., 2010). The isolated flower sterol nymphayol (20 mg/kg for 45 days) restored plasma glucose toward normal and increased plasma insulin in streptozotocin-diabetic rats, with more insulin-positive β-cells seen on pancreatic staining (animal study) (same review). Promising animal pharmacology, but not evidence of antidiabetic effect in humans.

Liver protection

An alcoholic flower extract (250–750 mg/kg orally for 10 days) protected rats against carbon-tetrachloride-induced liver damage, attributed to cell-membrane stabilization and activation of antioxidant enzymes (glutathione reductase, glutathione peroxidase, superoxide dismutase, catalase). A petroleum-ether seed extract (300 mg/kg) also prevented CCl₄-induced liver necrosis and mortality in rats and mice (animal studies) (Raja et al., 2010). These are chemical-injury models in rodents, not evidence for treating human liver disease.

Pain, inflammation and fever

An extract showed significant analgesic activity in the aconitine-induced writhing test in mice, and anti-inflammatory activity against carrageenan-induced rat paw edema that the review describes as comparable to hydrocortisone, plus antipyretic activity (animal studies) (Raja et al., 2010).

Antimicrobial activity (test tube)

Flowers of N. nouchali were effective against Pseudomonas aeruginosa, Bacillus cereus and Staphylococcus aureus, and an ethanolic leaf extract of N. stellata showed considerable antibacterial activity against E. coli (in-vitro studies) (Raja et al., 2010). Test-tube antibacterial activity does not translate into treating infections.

Sedation and a negative result

An alcohol extract of the defatted fruits produced mild sedation and ataxia in mice, potentiated hexobarbitone-induced sleep, and caused a sharp transient drop in blood pressure blocked by atropine: suggesting an unstable cholinergic principle (animal study) (Raja et al., 2010). Notably, a methanolic root extract showed zero inhibition in a tumor-promoter (EBV activation) screening assay: a published negative result against anticancer claims (same review).

Dosage

The review, citing the Ayurvedic Pharmacopoeia of India, records 3–6 g of the dried flower as the traditional dose (Raja et al., 2010). This is a pharmacopoeial/traditional figure, not a clinically validated dose, and the animal-study doses above cannot be converted into human doses.

Safety & contraindications

No published human safety data, pregnancy data, or drug-interaction studies for utpala were found: safety data is limited, so talk to a clinician before use. In animals, the LD50 of a 50% ethanol extract was 681 mg/kg in albino mice, and extracts showed sedative and blood-pressure-lowering effects, so caution is warranted with sedative or blood-pressure medicines (Raja et al., 2010). Traditional sources describe the flowers as mildly sedative/narcotic, which is consistent with the animal findings but is not a basis for using it as a sleep aid.

FAQs

Does utpala lower blood sugar?

Only in diabetic rats so far: leaf and flower extracts reduced hyperglycemia and improved lipids, and the isolated sterol nymphayol restored insulin levels in diabetic rats (Raja et al., 2010). No human study has tested utpala for diabetes, so it cannot be considered a blood-sugar treatment, and combining it with diabetes medicines would be unstudied and potentially risky.

Can utpala help with sleep?

There is no human evidence. Traditional sources call the flowers mildly sedative, and an animal study found a fruit extract caused mild sedation and prolonged barbiturate-induced sleep in mice (Raja et al., 2010). Animal sedation is a long way from a safe, effective sleep aid in people.

Is utpala the same as blue lotus?

Not exactly. "Blue lotus" is used loosely for several water lilies. Utpala in the pharmacopoeial sense is the flower of Nymphaea stellata (syn. N. nouchali); the Egyptian "blue lotus" is usually Nymphaea caerulea, and neither is a true lotus: the true lotus is Nelumbo nucifera (Raja et al., 2010). Products sold as "blue lotus" may be a different species.

What dose of utpala is used?

Classical and pharmacopoeial references record 3–6 g of the dried flower (Raja et al., 2010). This is a traditional figure with no clinical validation behind it, and it applies to the crude flower, not to concentrated extracts or commercial capsules.

Is utpala safe in pregnancy?

No pregnancy safety data exist for Nymphaea stellata. Animal studies show sedative and blood-pressure effects, and there are no human studies at all (Raja et al., 2010). It should be avoided in pregnancy and breastfeeding unless a qualified clinician advises otherwise.

Sources

Disclaimer

This article is for educational purposes only and is not medical advice. Herbal products can interact with medications and are not suitable for everyone. Talk to a qualified healthcare practitioner before use — especially if you are pregnant, breastfeeding, managing a medical condition, or taking prescription medicines.