Thermotherapy is the application of heat for the treatment of injuries and diseases. It improves the state of an injury by means of thermal agents, which are at different degrees of heat, on the organism. The physiotherapist can perform superficial thermotherapy or deep thermotherapy. Superficial refers to the degree of penetration being low either by infrared or with reflex mechanisms. It is profound when biological effects are produced by directly heating the deep tissues. Depending on the type of thermotherapy, the heat can be applied by radiation, conduction or convection. It is especially prescribed for rheumatic and chronic pains, colic and to increase the elimination of toxins.