Ammi daucoides, A. visnaga, bishop’s weed, greater Ammi, khella fruits, visnaga
Khella is derived from the fruits and seeds of Ammi visnaga, a member of the carrot family. One standardized form contains a minimum of 10% gammapyrones, calculated as 100 mg khellin. One constituent, visnadin, acts as a mild positive inotrope by dilating coronary vessels and increasing coronary and myocardial circulation. Another component, khellin, is commercially available and used as a vasodilator in treating bronchial asthma and angina pectoris. Khella is available as capsules, tablets, and tea, in products such as Doctor’s Choice for Heart Health.
Khella is used orally for angina pectoris, cardiac insufficiency, paroxysmal tachycardia, extrasystoles, hypertonia, asthma, whooping cough, and cramp-like complaints of the abdomen. Khella extracts are used topically for psoriasis.
- Capsules or tablets: Average daily dose is 20 mg gamma-pyrones by mouth. To increase HDL, take khellin 50 mg four times a day
- Tea: Khella is rarely used as a tea, but it’s prepared by pouring boiling water over the powdered fruits, soaking for 10 to 15 minutes, then straining.
Adverse reactions associated with khella include dizziness, headache, insomnia, nausea, constipation, lack of appetite, elevated liver transaminases and gammaglutamyl transferase, cholestatic jaundice, phototoxicity, skin cancer, and itching Using khella with hepatotoxic drugs may cause additive effects. Using it with digitoxin may decrease therapeutic effect and/or toxicity. Concomitant use of khella and alcohol may lead to hepatotoxicity. Khella may cause photosensitivity reactions.
Patients hypersensitive to khella or any of its components should avoid the herb. It shouldn’t be used by women who are pregnant or breast-feeding by patients pregna with liver disease, or by people who are prone to skin cancer.
- Oral use ofkhella may raise liver enzyme levels.
- Although chemical interactions to khella have not been reported in clinical studies, tell patient it may interfere with therapeutic effect of conventional drugs.
- Warn patient not to take khella for cardiac failure before seeking appropriate medical evaluation because doing so may delay diagnosis of a potentially serious medical condition.
- Advise patient to store khella away from children and pets.
- Warn patient against taking khella with alcohol or with hepatotoxic drugs.
- Tell patient taking khella to protect against sun exposure.
- Advise female patient to notify health care provider about planned, suspected, or known pregnancy before taking khella.
- Tell patient to notify pharmacist of any herbal and dietary supplements that he’s taking when obtaining a new prescription.
- Advise patient to consult his health care provider before using an herbal preparation because a conventional treatment with proven efficacy may be available.
The concepts behind the use of khella and the claims made regarding its effects haven’t yet been validated scientifically.