Dandelion Tea

• Daisy-family allergy: do not use if you are allergic to dandelion or to plants in the daisy family. Dandelion belongs to the daisy family (Asteraceae, also called Compositae), which includes ragweed, chrysanthemum, marigold, daisy and chamomile. The EU root and leaf monographs both list allergy to the plant or to this family as a contraindication, and list allergic reactions as a side effect of unknown frequency. The documented problem is skin allergy from touching the plant or its extract. In 7 people with suspected dandelion dermatitis, all 7 reacted to dandelion extract on a patch test. In 235 adults at one skin clinic, 3 (1.3%) reacted, all with eczema. In 388 Danish children, 6 of the 10 tested with dandelion extract reacted. These are skin tests in selected clinic patients, not drinking tea, and not the rate in the general public. NCCIH says evidence conflicts on whether dandelion triggers reactions in people sensitive to ragweed, chrysanthemums, marigolds and daisies. The EU assessor says anaphylaxis is possible in theory because of sesquiterpene lactones. Case series ^{18 15 17 19 7 6 10}
• Gallstones, bile-duct problems and liver disease: the EU advises against dandelion root. The 2021 EU root monograph says that, because dandelion root may stimulate bile secretion, it is not recommended with obstruction of the bile duct, cholangitis, liver disease, gallstones or any other bile disease. The older leaf monograph goes further and lists these, plus active peptic ulcer, as contraindications. This is the regulator's reasoning, not a list of injuries in people. The EU root monograph also says people told to limit their fluids should not use it for the urine indication, because it needs enough fluid to work. Authoritative guidance ^{18 15}
• Potassium: kidney failure, diabetes and heart failure. The older EU leaf monograph says use should be avoided with kidney failure, diabetes or heart failure because of possible high blood potassium (hyperkalaemia). The assessment reports explain why: dandelion leaf is rich in potassium (30 to 48 mg per g of dried leaf), and in the one tea they cite, 5 g of Spanish leaves steeped in 200 ml of water for 2 hours held 519 mg per litre. The assessor says tea made with such leaf should not be drunk together with potassium-raising medicines (listed under Medicines). These figures are for leaf, not root. The newer 2021 root monograph does not repeat this caution, and no figure for root tea was found. No case of high potassium caused by dandelion was found in the sources read. Authoritative guidance ^{15 17 16 18}
• Medicines: water pills, lithium, potassium-raising drugs and ciprofloxacin. No interaction has been reported in people (EU root and leaf monographs). The theoretical concerns are: water pills and lithium (dehydration and lithium build-up, because dandelion is called a diuretic, although the human evidence for that is weak); potassium-raising medicines (potassium content, leaf-based); and antidiabetes, blood-thinning and antiplatelet drugs (NCCIH, theory only). The one measured interaction is in rats: a water extract of a relative, Taraxacum mongolicum, cut the peak level of the antibiotic ciprofloxacin by 73%. See the interaction entries for details. If you take regular medicine, ask a pharmacist. Pharmacological theory ^{19 17 16 18 13 2 3}
• Pregnancy, breastfeeding and children: not enough data. The EU root and leaf monographs say safety in pregnancy and breastfeeding has not been established and do not recommend use for lack of data, and say use under 12 years has not been established. NCCIH says little is known about amounts above food levels in pregnancy and breastfeeding. LactMed finds no data on dandelion in nursing mothers or infants, calls dandelion generally recognized as safe as a food, and considers use while breastfeeding unlikely to harm the baby. Sources differ in tone; talk with a midwife or doctor. Authoritative guidance ^{18 15 19 20}
• Tea, roasted 'coffee' and extracts are different products. The EU monograph covers dandelion root as a herbal tea made by decoction, and also as liquid extracts and tinctures that contain alcohol. Both small human diuretic studies used an extract or capsules, not tea. Roasted dandelion root is sold as a coffee-style drink; a review of old folk-medicine writing says wine or coffee substitutes were among the preparations, but none of the sources read tests or discusses the safety of roasted root, how roasting changes it, or whether the allergy and bile cautions apply to it. Leaf, root and flower teas are also different parts, and NCCIH does not separate them. Do not carry results from one product to another. Authoritative guidance ^{18 4 2 3 19}
• Liver injury: one case with a mixed 'liver detox' tea. One case report describes a 36-year-old woman with acute liver injury (bile-flow pattern) after an over-the-counter liver-detox tea of six ingredients, one of them dandelion root. Dandelion cannot be blamed alone, and the authors say it was the first liver toxicity reported for any of the ingredients. No other liver report for dandelion was found, and LiverTox was not opened. Teas sold for 'detox' often mix several herbs. Case report ^{9 18}
• Foraged dandelion can carry metals. Dandelion takes metals up from soil, most in the root. Wild plants in the EU report held lead up to 45 mg per kg (29 US sites) and 175 mg per kg (13 Polish sites). A 2024 roadside study called it a lead hyperaccumulator. In a 2026 Polish study, 32% of the samples from five plant species were above the EU mercury limit, mostly self-collected ones. If you pick your own, avoid roadsides and industrial ground. These are plant analyses, not harm in people. Food analysis ^{17 11 1}

One published case links a six-herb liver-detox tea that contained dandelion root to acute liver injury with a bile-flow pattern. Dandelion cannot be blamed alone. The EU advises against dandelion root in liver disease and bile-duct disease. LiverTox was not opened. ^{9 18}

How often. No rate could be found.

Monitoring. No monitoring advice was read from an agency.

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This is a safety connection. It is not evidence that Dandelion Tea supports liver health.

Summary. No case of overdose has been reported (EU monographs). Reproductive toxicity and cancer tests have not been done, and genotoxicity tests have not been done (root monograph) or were not adequate (leaf monograph).

Animal. Not covered here beyond the rat ciprofloxacin study.

High dose or long term signals. Unknown. NCCIH says less is known about amounts larger than food.

Overdose response. No case reported.

Genotoxicity. Not tested (root) or not adequately tested (leaf) per the EU monographs.

Toxic or hazardous parts. The root, leaf and flower are used. No toxic part is named in the sources read.

Dandelion takes metals up from soil, so where it grew matters. These are plant analyses, not harm in a person.

Lead and cadmium in wild plants (EU assessment report). Wild plants from 29 US sites held lead 0.50 to 45.00 and cadmium 0.55 to 3.11 mg per kg; plants from 13 Polish sites held lead 3.3 to 175.3 mg per kg. ¹⁷

Lead hyperaccumulation. A study of 34 roadside samples found the highest trace-element levels in roots and called dandelion a lead hyperaccumulator. ¹¹

Mercury. 32% of samples from five plant species (including dandelion) were above the EU mercury limit, mostly self-collected ones, and mercury was highest in roots. Dandelion's median was 13.00 micrograms per kg. ¹

• Swelling of the lips, face or tongue, hives, wheeze or trouble breathing after dandelion: get emergency help.
• Yellow skin or eyes, dark urine, pale stools or severe belly pain (general warning signs of liver or bile-duct trouble, not from a dandelion-specific source): get medical help.
• Fever, painful urination, spasms or blood in the urine while using it for urinary complaints: see a doctor (EU monograph).
• Dizziness, faintness or very dark urine if you also take lithium or a water pill: contact your prescriber.

Stop using the product and contact a clinician or emergency service. In the US, Poison Control is 1-800-222-1222.