If it sounds too good to be true, it probably is.

Melanotan II – or the Barbie Drug – is a synthetic hormone injection that stimulates the body’s natural pigmentation process. It is available for sale via the Internet only, and it promises the perfect tan without harmful UV exposure. Each one-milligram dosage is inexpensive (approximately $4.50 per use), requires virtually no time commitment and produces a uniform glow without having to worry about the annoyance of tan lines or sunburn. As an added bonus, it even boots your libido.

But it’s not regulated, nor is it approved by the Federal Drug Administration (FDA).

It also makes you nauseous and dizzy, causes prolonged erections in men and may increase your risk of skin cancer. Or, worse still, it could kill you.

“There are so many potentially dangerous products on the market that lure in billions of dollars annually from patients who are either choosing to ignore the available scary information, or at times, just not follow their common sense and intuition,” says Brian Howard, MD, FACS, of North Fulton Plastic Surgery in Roswell, Ga.

So far one death has been reported in possible connection with the use of tanning injections. In 2012, 26-year-old Jenna Vickers from Bolton, Lancashire, U.K., was found dead in a tanning booth shortly after having injected herself with Melanotan II. It is unclear whether the injections played a part in her death, but the Medicines and Healthcare Products Regulatory Agency (MHRA) – the UK’s equivalent of the FDA – issued a warning against the product due to the lack of information regarding its safety.

Similarly, the FDA has issued two warning letters in relation to the product. The FDA has not yet commented on Melanotan II’s safety or lack thereof, but rather on the lack of research and documentation surrounding the product.

In 2007, the first warning letter was sent to Melanocorp, Inc., in Hendersonville, Tenn.; in 2009, the second was issued to US Lab Research, Inc. in Mentor, Ohio. In both cases, according to the letters – which can be found on the FDA’s official website – Melanocorp, Inc. and US Lab Research, Inc. falsely marketed the injections as intending to “prevent, treat or cure disease conditions or to affect the structure or function of the body,” without actually having any such documentation from the FDA.

That in and of itself should make anyone who considers using the product to tan at least question its safety.

“As with many fad treatments – such as HCG for weight loss – there are always consequences, and often marketing directly to the consumer does not adequately warn of side effects, or people just don’t take the time to read and understand warnings,” says David J. Levens, MD, FACS, of DLJ Plastic Surgery in Coral Springs, Fla. “It would seem that a product such as [Melanotan II] and others should only be used under a doctor’s supervision and/or obtained by a prescription.”

In addition to the side effects that have already been reported by users of the drug, there are two more potential dangers. For one, because the drug is not regulated by the FDA, you don’t know what you’re actually getting inside that vial. And second, there is no guarantee that the syringes provided are sterile.

With all of this knowledge, it seems best to avoid Melanotan II. In fact, it is best to avoid most types of sun tanning.

“We all know – although we all choose not to take seriously – the real harms of sun tanning,” says Dr. Howard. “Tanning beds are one of the main causes of skin cancers in our country so in reality, should be banned, in my opinion.”

Spray tans seem to be the least harmful option, though they don’t have full approval of the medical community, either.

“As [spray tanning] avoids exposure to UVA and UVB lights as with sunlight and tanning beds, it at least therefore eliminates the associated risks of skin aging, sun damage and skin cancer,” says Dr. Levens. But, “the safest tanning option is no tanning.”