Carboxytherapy is a treatment that began to spread in the early years of the twentieth century, when many members of high-society members spent long periods at the spa: it was almost forgotten in the second half of the last century and regained popularity in the early 2000s as an anti-cellulite treatment. This technique consists in putting carbon dioxide (in its gaseous state) in the area to be treated, through a needle connected to a machine. Carbon dioxide is a substance that is already present in the body and it does not represent a danger for the patient: it is injected with very thin needles, in order to reduce the sensation of pain.