A shocking new facial procedure is making the headlines and you might not want to read on if you're at all squeamish.
'Carboxy Therapy' involves injecting carbon dioxide (CO2) under the skin. Some practitioners claim it can reduce under-eye bags and dark circles.
The beauty treatment causes the eye area to immediately swell up after each injection of gas, making for a shocking sight.
A course of six to eight treatments is usually recommended. Side effects include swelling, redness, bruising and pain at the injection sites, which can last anywhere from one to five days.
Dr Sanjay Parashar, who performs carboxy therapy, claimed on Instagram that it "works on principles of the Bohr effect" - a physiological phenomenon in which an increase in CO2 concentration leads to decrease in pH.
According to Parashar, this "results in increased oxygen availability for the tissues," thus reducing dark circles.
Dr MediSpa, a clinic in Essex where the procedure is performed, claim that the risk of scarring is "very rare" and that there are "no long term side effects" reported so far - but the treatment should only be carried out by a surgeon.
The clinic also states that the injections can be used for stretch marks, skin tightening and fat loss.
Dr Anjali Mahto, consultant dermatologist at London's Cadogan Clinic, told The Huffington Post UK that more research needs to be done into the safety of carboxy therapy.
"There is limited if little scientific data on treatments such as this," she said.
"Treating dark circles can be notoriously difficult and a number of methods have been reported such as the use of brightening creams and agents, chemical peels designed specifically for the periorbital area, and other more invasive treatments such as PRP [Platelet-Rich Plasma] therapy or small amounts of hyaluronic acid dermal filler injections.
"All have been used with varying degrees of success but a certified dermatologist will be able to provide guidance on the best treatment for each individual."
Dr Olivier Amar, a surgeon at the Cadogan Clinic finds a type of PRP therapy known as the FAMI technique - pictured above - to be the most effective method of treating under-eye bags.
FAMI is a type of fat transfer in which stem cells are collected from fat tissue and then injected into the face under local anaesthetic.
“This is a minimally invasive procedure and much more effective and natural than using fillers," he said.
“By restoring volume around the orbital area to compensate the early stages of deflation of the temples, eyebrows and cheekbones, through the FAMI technique a ‘lift’ effect occurs which restores the patient’s own anatomy and volume.
"This results in a harmonious, natural and youthful appearance.”