Yew

Generic name: Taxus Bacatta L., Taxus Brevifolia Nutt., Taxus Canadensis Marsh., Taxus Cuspidata Sieb. And Zucc., Taxus Floridana Nutt., Taxus Yunnanensis
Brand names: Chinese Yew, European Yew, Ground Hemlock, Japanese Yew, Yew

Usage of Yew

Based on known toxicity, there are no current clinical uses of the plant.

Antibacterial activity against foodborne pathogens has been demonstrated with secondary bioactive metabolites produced from endophytic bacteria isolated from T. brevifolia seed, fruit, and leaves.(Islam 2018)

Yew side effects

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

Before taking Yew

Information regarding safety and efficacy in pregnancy and lactation is lacking. Avoid use.

How to use Yew

Crude preparations of yew needles or bark should not be used because of their cardiotoxicity caused by taxanes.

Warnings

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.(Labossiere 2018) The adult lethal dose of yew needles is reported to be 50 g, which is equal to 250 mg of taxine alkaloids (approximately taxine 3 mg/kg body weight)(Grobosch 2013) that have been primarily implicated in inducing cardiac toxicity. Taxine B alkaloids mediate cardiac toxicity by blocking sodium/calcium channels and tend to be resistance to standard treatments. Taxus brevifolia, the Pacific yew, contains lower levels of taxine and tends to be less poisonous. Most cases of poisoning are highly resistant to pharmacologic treatment.(Labossiere 2018)

Excluding the red aril of the berries, most of the plant is poisonous. Following ingestion, symptoms of dizziness, dry mouth, mydriasis, nausea, vomiting, and abdominal cramping develop rapidly. A rash may appear, and the skin can become pale and cyanotic. Bradycardia, hypotension, ventricular tachycardia and fibrillation, and dyspnea may be accompanied by coma, leading to death caused by respiratory or cardiac failure. A number of deaths in humans have been reported following the ingestion of yew leaves or teas brewed from yew. The administration of digoxin-specific FAB antibody fragments has been associated with the improvement of cardiac conduction abnormalities following ingestion of yew leaves and berries(Cummins 1990, Labossiere 2018); intensive treatment with antiarrhythmic drugs, temporary pacemaker, intra-aortic balloon pump, excessive diuresis, extracorporeal membrane oxygenation, and extracorporeal life support may also be required.(Grobosch 2013) A 24-year-old woman with Asperger syndrome and a history of depression attempted suicide by ingesting yew leaves; cardiogenic shock developed within 5 hours of ingestion despite immediate stomach flushing, activated carbon, and tentative application of digitalis antitoxin. Prolonged CPR (almost 4 hours), 24-hour therapeutic hypothermia, repeat digitalis antitoxin, and 24 hours of medical and mechanical cardiac support established a stable sinus rhythm with regular atriventricular conduction and complete recovery of biventricular function. No neurological deficits, organ damage, or significant repolarization disorders were sustained.(Baum 2015)

A 22- year woman was admitted to the emergency room with apnea and no pulse after ingesting an unknown amount of Taxus baccata. Immediately before admission, the patient was witnessed to have experienced a generalized tonic clonic seizure. An electrocardiogram revealed a wide complex rhythm with persistent cardiovascular collapse. Despite supportive care, the patient died. Perimortem serum demonstrated 3,5-DMP concentrations of 86.9 ng/mL, and taxine B concentrations of 80.9 ug/mL.(Arens 2016) Yew-induced thrombocytopenia subsequent to consuming Chinese yew tea (T. yunnanensis) has been documented in a 53-year-old female that was cOnfirmed with hospital re-challenge. Two other cases of yew-induced thrombocytopenia due to tea containing T. cuspidata extracts (Japanese yew) have also been reported.(Ubukawa 2019)

Several other cases of fatal and non-fatal intentional, as well as accidental, ingestion of yew leaves have been documented.(Grobosch 2013, Labossiere 2018)

What other drugs will affect Yew

Formal drug interaction studies have not been performed with Yew ingestion.

Disclaimer

Every effort has been made to ensure that the information provided by Drugslib.com is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Drugslib.com information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Drugslib.com does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Drugslib.com's drug information does not endorse drugs, diagnose patients or recommend therapy. Drugslib.com's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners.

The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Drugslib.com does not assume any responsibility for any aspect of healthcare administered with the aid of information Drugslib.com provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Popular Keywords