Heat therapy relaxes you; loosens muscles and ligaments; dilates blood vessels; boosts circulation; increases metabolic processes; warms the skin and, of course, makes you sweat. So, heat therapy in Ayurveda is called sweda karma (sweda means sweat). This is one of the prerequisites for Ayurvedic Panchakarma Therapies.

Heat works to promote wound healing. When applied to a wound, heat raises the metabolic rate. The resulting increased blood flow carries away waste products and provides a greater supply of nutrients and infection fighters to the affected area. It helps reduce the pain of arthritis and sore muscles. It is also used for treating cancerous tumours. Ayurvedic classics have described a wide range of fomentation procedures, which are classified into different categories depending upon various factors:

1. Whether it involves agni (fire) or not. (agni sweda or niragni sweda).

2. Is it used for a specific part of the body (ekaanga sweda) or the whole body (sarvaanga sweda). Generally, locally applied heat as in hot packs can be better for wounds, muscle and skeletal injuries; heat therapy for the whole body is generally for relaxation.

3. Whether the fomentation is wet (snigdha) or dry (rooksha). Moist heat is thought to penetrate deeper than dry heat and so may be better for sore muscles or injured ligaments. Some skin ailments may benefit from less penetrating dry heat.

Ayurveda recommends heat application in all Vaata, Kapha and Aama disorders. Heat can be effective supporting therapy in case of many diseases like bronchial asthma, cough, catarrh, hiccups, bloated belly, inactivity, catch in waist, sides and back, painful urination, urinary stones, turnours, paralysis of the limbs, loss of sense in the limbs, etc.

However, for those with poor blood circulation, diabetes or heart disease, heat therapy should be used only under a doctor's supervision. It is not for expectant mothers, children and aged persons.

Ayurveda has restricted its usage in case of bleeding disorders, diarrhoea, debility and indigestion. Also fomentation will not give the desired results if you are mentally disturbed by emotions like fear, sorrow or anger.

Heat application in the pubic region should be milder than for other regions. Testicles, eyes and chest must be covered properly while taking this heat therapy. Among the wide range of fomentation procedures, some of the important ones are described in the formentation procedures section