Ancient Ayurvedic physicians had developed certain dietary and therapeutic measures to arrest or delay ageing and rejuvenating whole metabolism of the body system.This revitalization and rejuvenation is known as Rasayan Chikitsa.Rasayan does not mean only rejuvenation or delayed ageing, neither it means only revitalization.Rasayan is one the eight clinical specialties of Ayurveda.Rasayan is not only a drug therapy but is a specialized procedure practiced in the form of rejuvenative recipes ,dietary regimen and special health promoting conduct and behavior.
The management which helps to live a person longer ,which helps to keep intellectual capacity  and energy intact and which also helps to get acquit of the disease is known as rasayan.

Ayurveda emphasizes on improving the health conditions of a person rather than curing the diseases alone. This can be achieved easily through the Rasayana chikitsa. The treatment helps to repair the body by rejuvenating the tissues and give the person a young look by holding back the aging processes. Rasayana helps in physical, mental and spiritual well being of the body. This treatment helps to boost the ojas which means the vital force of life and also the immunity of a person. A person is said to be ojaswi if he is in good health at all times and in all seasons. Ojas gives a person a sharp memory, brilliant performance & extreme pleasure etc.

Rasayan is responsible for longevity, outstanding memory, intelligence par excellence, health, youth, complexion, melodious voice, strength of body sense organs & power of expressions vigor etc. Rasayan is one of the acclaimed concepts that deals with the rejuvenation of physical body and wellbeing of psyche.
Many rasayan formulations are prescribed in ayurveda like chyawanprash rasayan, amalki rasayan, brahama rasayan, pippali rasayan, yestimadhu medhya rasayan, shilajeet rasayan and bhallatak rasayan. Some of these rasayan work as immunomodulator, antioxidant, antistress cytoprotective and nutritive.
The factors like the patient’s age, sex, habits, living condition, type of disease etc are taken into consideration and the rasayan are chosen accordingly