Carboxytherapy is a relatively new cosmetic procedure that proponents claim can rejuvenate the skin around the eyes. The procedure involves injecting the areas around the eye with carbon dioxide. At first this causes severe swelling at the injection site.
The claim is that as the CO2 is removed by the blood circulating through the tissue. However the excessive amount of the gas causes the blood vessels to dilate, allowing them to carry more blood, effectively restoring color to the aging tissue.
The recovery time for this treatment is shorter than most alternative methods, but the results are contentious at best. While some claim that carboxytherapy is the greatest beauty treatment since Botox, others are less confident in its rejuvenating abilities.
In fact, there is no scientific evidence at all that show carboxytherapy to be effective. Biologically speaking, it doesn't address the underlying cause of dark circles that form under the eyes, which has little to do with blood flow. Those circles are caused by the thinning of the skin under the eyes, causing it to become somewhat transparent. This allows the underlying tissue to be partially visible.
Only a few studies have been done on the effectiveness of the procedure, and almost none have been peer reviewed. The two studies most cited by proponents show results that are debatable at best. In both tests the difference in the before and after photos of patients that have had carboxytherapy could be attributed to changes in lighting when the photos were taken.
Ironically, the massive amounts of swelling that occurs during the treatment may actually be exacerbating another common cosmetic issue found near the eyes; wrinkles. By stretching the thin skin just below the eyes it is then less likely to fully contract, and may appear more wrinkled than it did prior to the carboxytherapy.