Yew
Scientific Name(s): Taxus bacatta L., Taxus brevifolia Nutt., Taxus canadensis Marsh., Taxus cuspidata Sieb. and Zucc., Taxus floridana Nutt.
Common Name(s): European yew, Ground hemlock, Yew
Medically reviewed by Drugs.com. Last updated on Jun 9, 2022.
Clinical Overview
Use
Based on known toxicity, there are no current clinical uses of the plant. The semisynthetic taxane chemotherapy agent, docetaxel, was originally extracted from the needles of T. baccata.
Dosing
Crude preparations of yew needles or bark should not be used because of their cardiotoxic taxanes.
Contraindications
Contraindications have not yet been determined. There are no clinical uses of the plant due to toxicity.
Pregnancy/Lactation
There are no adequate and well-controlled studies of taxanes in pregnant women. However, animal studies have demonstrated embryo and fetotoxicity as indicated by intrauterine mortality, increased resorptions, and increased fetal deaths. Animal studies also have demonstrated high concentrations of taxenes in milk. Use in lactating women is not recommended.
Interactions
As most of the plant is poisonous, formal interaction studies have not been performed.
Adverse Reactions
The ingestion of the plant results in dizziness, dry mouth, mydriasis, and abdominal cramping. Rash and pale, cyanotic skin may develop. Eventually, ingestion may result in death.
Toxicology
Excluding the red aril, most of the plant is poisonous. Fatal and nonfatal suicidal yew ingestion has been documented as well as accidental poisonings in humans and animals.
Scientific Family
- Taxaceae
Botany
This evergreen is found throughout woods and forests and often is used as an ornamental hedge. The trunk supports a crown of spreading branches with long, narrow, dark green, shiny leaves. It is dioecious, with male and female flowers being produced on different trees. The ovoid seed is black and is surrounded by a red, fleshy covering called the aril. Yews flower in March and April.
History
The Celts coated their arrows with yew sap as a nerve poison. The alkaloid taxine has been used as an antispasmodic.Schauenberg 1990
Chemistry
The entire plant, with the exception of the red, fleshy aril, contains many taxane alkaloids, of which the best known is taxine.Cummins 1990 Other alkaloids (eg, milossine, ephedrine), the glycoside taxicatin and its derivativesSenilh 1984 and pigments are found throughout the plant family.
Uses and Pharmacology
Based on known toxicity, there are no current clinical uses of the plant.
Dosing
Crude preparations of yew needles or bark should not be used because of their cardiotoxicity caused by taxanes.
Pregnancy / Lactation
Information regarding safety and efficacy in pregnancy and lactation is lacking. Avoid use.
Interactions
Formal drug interaction studies have not been performed with Yew ingestion.
Adverse Reactions
Hypersensitivity reactions
Cross-sensitivity to the chemotherapeutic agent docetaxel and paclitaxel has been reported in cancer patients with allergies to T. baccata.
Cardiovascular
Bradycardia and hypotension have been documented with ingestion of the plant.Michaud 2000
Toxicology
Lethal doses of yew leaves are highly species specific and minimum lethal dose can range from 0.6 to 1.3 g of leaves/kg in humans (approximately 5 mg of taxine/g of leaves), which is approximately 3 to 6.5 mg of taxine/kg of body weight.
