Ammi visnaga (Linn.) Lam

Synonym-  Daucus visnaga Linn.Visnaga daucoides Gaertn.
Family-  Umbelliferae; Apiaceae.
Habitat-  Cultivated as a garden ornamental; runs wild at many places in Jammu region.
English-  Khella.
Folk-  Paashaanabhedi (controversial;Bergenia ligulata has been equated with the classical Paashaanabheda).
Action-  Antispasmodic in renal colic, bronchial asthma, whooping cough (used by Unani physicians),
vasodilator (in angina pectoris).

Key application-  German Commission E approved the herb on 13 March 1986, but due to information on potential risks, its status was changed to unapproved on 15 April 1994.Khella contains khellin (1%), visnagin,khellol glycoside, flavonoids,sterols, volatile oil (0.2%). Khellin and visnagin exert a powerful antispasmodic effect on the smaller bronchial muscles, the coronary arteries and on the urinary tubules. Khellin provides relief to asthmatic patients. The drug also relieves painful spasm of stone in kidney and bladder (no more used for expelling kidney stones).Khella does not reduce blood pressure in spite of being a vasodilator.Khellin is toxic at 100 mg. (Francis Brinker.)Khella is used topically for vitiligo and psoriasis. The Khellin constituent is similar to the psoralen nucleus andmight be useful as a photosensitizer in patients with psoriasis. (Natural Medicines ComprehensiveDatabase,2007.)(Several modern drugs including

amiodarone, nifedipine and cromolyn have been developed from Khella.)