Herbal Tea & Extract Safety

Read this first.

• Poisoning, overdose or collapse (US): Poison Help is 1-800-222-1222. Call 911 if someone has collapsed, had a seizure, has trouble breathing or cannot be woken. [1][2] For other countries, see Poison Help by country.
• Allergic reaction: NCCIH lists severe allergic reactions, including anaphylaxis, as possible with chamomile, and says they are more likely in people allergic to related plants such as ragweed, chrysanthemums, marigolds or daisies. [3]
• Possible liver trouble: NCCIH lists fatigue, nausea, poor appetite, dark urine and jaundice as liver damage symptoms (in its turmeric guidance). [4] Contact a clinician if these appear after starting a new herbal product. See liver injury warning signs.
• Licorice root: it can cause irregular heartbeat and cardiac arrest, especially in large amounts or over a long time. [5]

A tea is not harmless just because it is diluted or sold as a food. NCCIH puts it this way: "natural" does not always mean "safe." [6] This page is a map of what the sources we read say, with links to deeper pages. It is information, not personal advice.

What the sources can and cannot tell us

Most herbal teas have very little tea-specific safety research. Many European regulator statements say safety "has not been established," which means data are missing, not that harm has been shown. [7] For some teas the picture is calmer: NCCIH says chamomile is likely safe in the amounts found in teas, and that peppermint tea appears safe, while the long-term safety of large amounts of peppermint leaf is unknown. [3][8]

Proper evidence not found: a review that compares the safety of herbal teas as a group. We searched PubMed on 23 October 2026 for herbal tea safety in pregnancy, liver injury and kidney injury and found single-plant papers and case reports, not a group comparison. [9] Case reports show that a harm can happen, not how often.

Cautions by tea

"None reported" means the source does not list one, not that none exist. EU monograph statements describe herbal medicines, not every tea bag. True tea (green, black) is covered under Functional Foods; NCCIH reports no safety concerns for green tea as a drink in adults, with liver injury reported mainly from extracts. [30]

Medicines

Some interactions are reported in people, some are theoretical, and some are only from animal studies. Labelling them matters: see Herbal Tea and Medicine Interactions and how interactions work. A pharmacist can check your medicine list against your teas. Do not stop a prescribed medicine on your own; ask the prescriber.

Pregnancy, breastfeeding, babies and children

The NHS (UK) says to limit herbal tea to no more than 4 cups a day in pregnancy and to avoid teas containing licorice root, noting there is not much research. [11] NCCIH says many dietary supplements have not been tested in pregnant women, nursing mothers or children. [6] Details are on the pregnancy, breastfeeding and babies and children pages.

Liver and kidneys

LiverTox records say chamomile, ginger and licorice have not been linked to clinically apparent liver injury, while comfrey, which contains pyrrolizidine alkaloids, can cause sinusoidal obstruction syndrome and severe liver injury when taken by mouth. [31][32][33][34] See liver and kidney cautions and comfrey and coltsfoot teas.

Alcohol, contamination and mix-ups

MotherToBaby says tinctures and liquid products can contain alcohol, which should be avoided in pregnancy. [35] See alcohol in herbal extracts. MotherToBaby also notes that herbal products might contain metals, pesticides, microorganisms or ingredients not on the label. [35] A study of 200 chamomile samples found 7.5% contaminated with botulinum spores, more often in loose chamomile than in tea bags. [36] Plant mix-ups are real: a pediatric report found Chinese star anise contaminated with Japanese star anise. [37] See adulteration, mold and mislabeling and quality testing.

Before surgery

NCCIH says certain dietary supplements may increase the risk of bleeding or affect your response to anesthesia, and to tell your providers about all supplements you take. [6] The sources we read do not describe each tea separately, so mention herbal teas too. See herbal tea before surgery.