Cinchona (Rubiaceae)

Traditional sources describe Cinchona (Rubiaceae) as follows: Antimalarial & Fever-Reducing: Historically the primary source of quinine for malaria. Bitter Tonic & Antispasmodic: Stimulates digestive secretions, improves appetite, and may help certain muscle spasms. Astringent & Antibacterial: Used as a gargle for sore throats and sometimes for dysentery. Cardiac Effects: Contains quinidine, which can help regulate heart rhythm and slow heart rate.

Preparation amounts are not shown for this herb. It is toxic, restricted, or otherwise unsafe to self-dose - the margin between a traditional dose and a harmful one is too small to publish as reference material. If you are considering it, that conversation belongs with a doctor or a qualified practitioner, not a website.

Cinchonism: Quinine and the related alkaloids cause a recognized toxicity syndrome - ringing in the ears, hearing loss, headache, nausea, blurred vision and dizziness - and it begins at doses close to the ones traditional texts describe. Blood: Quinine can trigger severe immune thrombocytopenia, a sudden collapse in platelet count, and hemolysis in people with G6PD deficiency. These reactions are unpredictable and can follow a single exposure. Heart: The bark contains quinidine, an antiarrhythmic that prolongs the QT interval and can itself provoke dangerous rhythms. Avoid alongside other QT-prolonging medicines. Interactions: Quinine and quinidine interact with anticoagulants, digoxin, other antiarrhythmics, and many drugs cleared by the liver. Pregnancy and breastfeeding: Avoid. Higher doses are oxytocic and have been associated with harm to the fetus. General: Regulators have withdrawn or restricted over-the-counter quinine products because of these risks. Cinchona bark is not something to self-dose - malaria and heart-rhythm problems both need medical care.