The use of medicated oils, either internally or externally, is called Snehan (oleation). Snehan refers to the administration of medicated fats or the massage of oil over the skin for a specific period.
The use of oleation results in unctuousness and softness of morbid doshas, which become easily extractable and ready to move from places where their occupation is undesirable and unwarranted.
Snehan is performed using substances of vegetable origin such as Til, Erand, Mahua, Sarson, Neem, Karanj, Shaijan, Priyal and Bahera, as well as substances of animal origin such as milk, curd, Ghee, meat, fat and bone tissue. The use of a specific snehan substance also depends upon the season of treatment. Therefore, while the use of Ghee has been recommended during the fall season, oil is the preferred substance during winters and the use of fat and bone marrow has been recommended during the spring season.