No, you don’t need the ‘Barbie drug’ to tan, whatever TikTok says. Here’s why melanotan-II is so risky

TikTok and Instagram influencers have been peddling the “Barbie drug” to help you tan.

But melanotan-II, as it’s called officially, is a solution that’s too good to be true. Just like tanning, this unapproved drug has a dark side.

Doctors, researchers and Australia’s drug regulator have been warning about its side effects – from nausea and vomiting to brain swelling and erection problems.

There are also safer ways of getting the tanned look, if that’s what you’re after.

What is melanotan-II?

No, it’s not a typo. Melanotan-II is very different from melatonin, which is a hormonal supplement used for insomnia and jet lag.

Melanotan-II is a synthetic version of the naturally ocurring hormone α-melanocyte stimulating hormone. This means the drug mimics the body’s hormone that stimulates production of the pigment melanin. This is what promotes skin darkening or tanning, even in people with little melanin.

Although the drug is promoted as a way of getting a “sunless tan”, it is usually promoted for use with UV exposure, to enhance the effect of UV and kickstart the tanning process.

Melanotan-II is related to, but different from, melanotan-I (afamelanotide), an approved drug used to treat the skin condition erythropoietic protoporphyria.

Melanotan-II is not registered for use with Australia’s Therapeutic Goods Administration (TGA). It is illegal to advertise it to the public or to provide it without a prescription.

However, social media has been driving unlicensed melanotan-II sales, a study published last year confirms.

There are many black market suppliers of melanotan-II injections, tablets and creams. More recently, nasal sprays have become more popular.

What are the risks?

Just like any drug, melanotan-II comes with the risk of side effects, many of which we’ve known about for more than a decade. These include changes in the size and pigmentation of moles, rapid appearance of new moles, flushing to the face, abdominal cramps, nausea, vomiting, chest pain and brain swelling.

It can also cause rhabdomyolysis, a dangerous syndrome where muscle breaks down and releases proteins into the bloodstream that damage the kidneys.

For men, the drug can cause priapism – a painful erection that does not go away and can damage the penis, requiring emergency treatment.

Its use has been linked with melanoma developing from existing moles either during or shortly after using the drug. This is thought to be due to stimulating pigment cells and causing the proliferation of abnormal cells.

Despite reports of melanoma, according to a study of social media posts the drug is often marketed as protecting against skin cancer. In fact, there’s no evidence to show it does this.

Social media posts about melanotan-II rarely mention health risks.

There are no studies on long-term safety of melanotan-II use.

Then there’s the issue of the drug not held to the high safety standards as TGA-approved products. This could result in variability in dose, undeclared ingredients and potential microbial contamination.