The Rasayana therapy is a clinical speciality of Ayurveda that helps nourish the whole body by strengthening the Rasa Dhatu, the essence of all food we take, and which the body assimilates. Rasayana therapy contains various methods of rejuvenation. The benefits of Rasayana therapy are:

1. To increase the strength body tissues (Rasa)
2. To increase digestive power
3. To increase the functional capacity of the brain
4. To increase the strength and immunity of the body
5. To destroy diseases in the body
6. To delay aging process
7. To develop barrier against stress and infection 

Rasayana therapy includes drugs, dietary regimens and codes of conduct. The possible mechanisms of action of rasayana therapy are: Antioxidant, Immunomodulatory, Anti-ageing, Nutritive, Anabolic and Neuroprotective actions.

Classification of Rasayana

1. Dravaya Rasayana: This includes Ayurvedic herbs and foods which are useful for optimum functioning of the body and brain. There are four types of dravaya:

• Age-promoting Rasayanas: These herbs and diets provide stability to life, vitality, stamina, glow to the skin, sweetness to the voice, and virtually tend to enhance the life span of person. Popular example is Chyavanprash.
• Mental acuity enhancing Rasayanas: These rasayanas act as effective brain tonic and may help in increasing the intelligence and memory. They enhance the grasping, concentration and retention power of an individual and help in fighting mental fatigue. Examples of these rasayanas include cow’s milk and ghee, herbs like bramhi, vacha, and shankhpushpi, and bhrama rasayana
• Eyesight promoting Rasayanas: These are beneficial for and may promote proper functioning of the eyes thereby aiding a clear vision. These include Ayurvedic herbal formulations like aamalki rasayana.
• Disease combating Rasayanas: Here, specific rasayanas are given to the patients suffering from some particular disease. For example, bhallataka rasayana is used in diseases of skin and pippali rasayana is for respiratory diseases. 

1. Adravya Rasayana: Here, general rules of living and natural regimen of seasons are to be followed. All benefits of rasayana therapy can only be achieved if these good conducts are practiced on regular basis. 

• Avoid anger
• Be Truthful, free from ego
• Avoid consumption of alcohol, indulgence in sex and violence
• Period of awakening and sleep should be regular
• Practice self-control
• Consume milk and ghee regularly
• Respect elders and teachers
• Practice spirituality 

Some Important Rasayanas

References 

1. Anil Kumar Singh et al, Rasayana therapy: A magic contribution of Ayurveda for healthy long life, Int. J. Res. Ayurveda Pharm, 5(1), Jan-Feb 2014.
2. http://www.care2.com/greenliving/rasayana-the-ayurveda-therapy-of-rejuvenation.html
3. Charak Samhita of Agnivesha. Vidhyotini Hindi Vyakhya- Sastry K & Chaturvedi G – Editors. Chaukhambha Bharati Academy, Varanasi 221001. Reprint 2011.