Uses of Withania somnifera (Linn) Dunal (Ashwagandha) in Ayurveda and its Pharmacological Evidences

Withania somnifera (Linn) Dunal commonly known as Ashwagandha belongs to the family Solanaceae (nightshade family) which has got 1250 species widely distributed in the warmer parts of the world. The genus Withania is reported to have 23 species and out of which Withania somnifera (Linn) Dunal and Withania coagulans Dunal are of high medicinal value. Various preparations and forms of Withania somnifera (Linn) Dunal (Ashwagandha) i.e. powder, decoction, oil, smoke, poultice etc. have been advised for the cure of various disorders such as skin disorders, nervous disorders, intestinal affections, venereal diseases, rheumatism, emaciation of children and as a tonic for all kinds of weakness and in geriatrics. It also promotes vigor and stamina and is regarded as aphrodisiac and rejuvenator. The plant is usually erect, branched, unarmed shrub, up to 1.25 meters height and grows throughout the drier parts and sub-tropical India. Mainly cultivated in Madhya Pradesh and Rajasthan and it has huge internal consumption in India and also being exported. It is prone to several pests and diseases which need to be take care during cultivation. Withaferin A and Withanolide D are two main withanolides contribute to the most of biological actions. It has pharmacological action in almost all systems of the human body. It has also some side effects and contraindication. Number of pharmacological studies have been conducted and a wide range of biological activities have been observed such as anti inflammatory property, hepato-protective activity, infertility activity, anti bacterial activity, psychotropic/anti anxiety activity, anti convulsant activity, skin care activity, healthy hair activity, immune-modulator activity, anti peroxidative action, anti ageing effect, macrophage activating effect, haemopoitic effect, antibiotic activity, antitumour activity, anti-hyperglycemic effect, morphine tolerance and dependence-inhibiting effect, cardio tonic activity, hypo lipidemic, anti-atherogenic activity, positive inotropic activity, hypoglycemic effect, anti-oxidant activity, anti-carcinogenic activity etc. This review presents morphology of the plant, geographical distribution, cultivation and market value, plant pathology, Ayurvedic properties, chemical ingredients, medicinal uses in Ayurveda, side effects and contraindications, pharmacological evidences of Withania somnifera (Linn) Dunal (Ashwagandha).