Generally the basic concepts of the Siddha medicine are almost similar to ayurveda. The only difference appears to be that the siddha medicine recognizes predominance of vata, pitta and kapha in childhood, adulthood and old age, respectively, whereas in ayurveda, it is totally reversed: kapam is dominant in childhood, vata in old age and pitham in adults.

According to the Siddha medicine, various psychological and physiological functions of the body are attributed to the combination of seven elements: first is saram (plasma) responsible for growth, development and nourishment; second is cheneer (blood) responsible for nourishing muscles, imparting colour and improving intellect; the third is ooun (muscle) responsible for shape of the body; fourth is kollzuppu (fatty tissue) responsible for oil balance and lubricating joints; fifth is elumbu (bone) responsible for body structure and posture and movement; sixth is moolai (brain) responsible for strength; and the last is sukila (semen) ...more

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Ayurveda: The doctrine of Ayurveda aims to keep structural and functional entities in a functional state of equilibrium, which signifies good health. Any imbalance due to internal and external factor causes disease and restoring equilibrium through various techniques, procedures, regimes, diet and medicine constitute treatment. The philosophy of Ayurveda is based on the theory of Pancha bhootas (five element theory) of which all the objects and living bodies are composed of.
Siddha: Siddha system of medicine emphasize that medical treatment is oriented not merely to disease, but also has to take into account the patient, environment, age, habits, physical condition. Siddha literature is in Tamil and it is largely practiced in Tamil speaking parts of India and abroad.

Ayurveda: The doctrine of Ayurveda aims to keep structural and functional entities in a functional state of equilibrium, which signifies good health. Any imbalance due to internal and external factor causes disease and restoring equilibrium through various techniques, procedures, regimes, diet and medicine constitute treatment. The philosophy of Ayurveda is based on the theory of Pancha bhootas (five element theory) of which all the objects and living bodies are composed of.
Siddha: Siddha system of medicine emphasize that medical treatment is oriented not merely to disease, but also has to take into account the patient, environment, age, habits, physical condition. Siddha literature is in Tamil and it is largely practiced in Tamil speaking parts of India and abroad.

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Both Siddha and Ayurveda recognize that disease is caused by the imbalance of the three humors. But Siddha sees the predominance of humors as vatham, pitham and kapam in childhood, adulthood and old age respectively while Ayurveda views the dominance of kapam in childhood, vatham in old age and pitham in adulthood

Ayurveda focuses on five elements of earth, water, fire, air and ether which affect the blood, chyle, flesh, fast, bone marrow and semen. Ayurveda also attributes experiences of human life as 20 gunas or qualities. It uses surgery, yoga, meditation and massage techniques. Siddha focuses on seven elements saram (plasma) for growth, cheneer (blood) for nourishment of muscles, ooun (muscle) for body shape, kollzuppu (fatty tissue) for oil balance and lubrication of joints, enbu (bone) for body posture, moolai (nerve) for strength and sukila (semen) for reproduction.