Tussilago japonica

Tussilago japonica contains tussilagone, a terpene ketone that acts on the respiratory center to suppress coughing. The herb also contains saponins and mucilaginous compounds that coat and soothe irritated mucous membranes in the throat and respiratory tract. In Traditional Chinese Medicine, it is classified as a warming herb that disperses cold from the lungs, making it specifically indicated for cold-type coughs with clear phlegm. Evidence level: C (preliminary pharmacological studies and traditional use).

Tussilago japonica may interact with hepatotoxic medications due to its pyrrolizidine alkaloid content, which can compound liver stress. Patients taking acetaminophen, statins, antifungals, or other liver-metabolized drugs should avoid concurrent use. Alcohol consumption should also be avoided during use. Limited clinical data exists on specific drug interactions, so patients on prescription medications should consult a healthcare provider before use. Evidence level: C (theoretical interactions based on constituent profile).

The typical adult dosage for Tussilago japonica is 5-9 grams of dried flower buds daily, prepared as a decoction. Standardized extracts are typically dosed at approximately 300mg daily. Dosage should be strictly limited to recommended amounts due to pyrrolizidine alkaloid content, and long-term use is not advised. Treatment duration should be minimized to reduce hepatotoxicity risk. Evidence level: C (based on traditional use and pharmacopoeia standards).

Tussilago japonica is contraindicated during pregnancy and breastfeeding. The herb contains pyrrolizidine alkaloids, which are known hepatotoxins that can cross the placenta and pass into breast milk. These compounds pose risks of liver damage and potential developmental toxicity to the fetus or nursing infant. Women who are pregnant, planning pregnancy, or breastfeeding should avoid this herb entirely. Evidence level: C (safety concerns based on constituent toxicity).

Tussilago japonica is used in Traditional Chinese Medicine for cold-type coughs, asthma, bronchitis, and hoarseness. As a warming lung herb, it is specifically indicated when cough is accompanied by clear or white phlegm, aversion to cold, and no sore throat. It is not appropriate for dry, hot coughs with yellow phlegm. The flower buds are the primary medicinal part used. Evidence level: C (supported by traditional use and preliminary antitussive research).

The primary safety concern is hepatotoxicity from pyrrolizidine alkaloids, which can cause veno-occlusive liver disease with high doses or prolonged use. Symptoms may include jaundice, abdominal pain, fatigue, and elevated liver enzymes. Individuals with pre-existing liver disease should avoid this herb entirely. Proper processing and strict adherence to recommended dosages reduces but does not eliminate risk. Evidence level: C (documented hepatotoxic potential of pyrrolizidine alkaloids).