Withania somnifera is a medicinal plant which spreads over a large area, ranging from the Atlantic Ocean to South East Asia and from the Mediterranean region to South Africa. Medicinal plants are widely used to treat various diseases by conventional medical practitioners in their daily practice. Withania somnifera in conventional medical systems, for the treatment of aphrodisiac, liver tonic, anti-inflammatory agent, astringent and, more recently, for the treatment of bronchitis, asthma, ulcers, emaciation, insomnia and senile dementia, different parts of Withania somnifera (leaves, stems, bulbs, roots, seeds, bark and even whole plants) (known as Ashwagandha in Hindi), a small herb seen throughout India, have been recommended. Ashwagandha is also used therapeutically as an adaptogen in patients with stress-related nervous fatigue, insomnia, and weakness, and as an immune stimulant in patients with low blood counts of white blood cells. In a class of constituents called withanolides, steroidal alkaloids and steroidal lactones are the main biochemical constituents of the ashwagandha root.