Carboxytherapy consists in the intradermal injection of carbon dioxide (CO₂) into the tissues. The properties of this gas are multiple: it improves microcirculation, boosts local metabolism, and, in relation to fat, is lipolytic ("fat burning"). The body produces CO₂ naturally, at a rate of 200 ml per second. This amount may be ten times higher during exercise.
The determinant for combating sagging skin is postulated by the Bohr effect, which translates to a supply of oxygen to tissue being treated with this gas. This increase of oxygenation favors the formation and replenishment of collagen and elastin, increasing tension of the dermis. Additionally, it expands blood vessels, which affords the additional supply of nutrients necessary to remodel the components of the extracellular matrix, and to induce tissue repair.
CO₂'s fat-burning properties are due to its distension of tissues, causing insufflation of the area and the release of different substances, which bind to receptors and activate lipolysis, or the breakdown of fats.