If you have used Melanotan-II and noticed new or changing moles, you may be wondering what those changes mean and whether you should be concerned.
Recent reports have drawn attention to people developing new, darker or unusual looking moles after using Melanotan-II (MT-II), an unapproved tanning peptide promoted online and through social media.
The important message is not to panic or assume that a changing mole is melanoma. There is currently no evidence proving that Melanotan-II causes melanoma. There are, however, reports of new and changing moles following its use, as well as individual cases in which melanoma has been diagnosed.
If you have used Melanotan-II and noticed changes in your skin, tell your doctor and have any concerning spots assessed.
What is Melanotan-II?
Melanotan-II, often called MT-II, is a synthetic peptide that acts on the body's melanocortin system. One of its effects is to stimulate melanocytes, the cells in our skin that produce the pigment melanin.
This increase in melanin can make the skin appear darker.
Melanotan products may be promoted online using terms such as "tanning peptide", "tanning injection", "nasal tanning spray" or "Barbie drug". Products may be sold in injectable, nasal spray, tablet, cream or other forms.
In Australia, Melanotan-II is a prescription-only medicine and is not approved for sale or use as a tanning agent. There are currently no products containing Melanotan-II on the Australian Register of Therapeutic Goods (ARTG) or approved for supply in Australia.
Why are doctors concerned about Melanotan-II and changing moles?
One reason for concern is the effect Melanotan-II can have on melanocytes and pigmentation.
Medical literature has described changes occurring after Melanotan use, including:
- existing moles and freckles becoming darker
- new moles appearing
- changes in the size or appearance of existing moles
- the development of atypical or dysplastic-looking moles.
Individual case reports have also described melanoma being diagnosed in people who had used Melanotan-II.
These reports are important, but they need to be interpreted carefully.
A case report can identify something unusual that has occurred in an individual patient, but it cannot establish that one thing caused another. At present, research has not established a causal relationship between Melanotan-II use and melanoma.
There are also other factors that affect an individual's melanoma risk, including UV exposure, previous sunburn, skin type, family history, personal history of skin cancer and the number and type of moles a person has.
Some people using Melanotan-II may also deliberately expose their skin to the sun or use tanning devices in an attempt to increase tanning. UV radiation itself is a well-established cause of skin cancer.
What does the research tell us?
Concerns about Melanotan-II and changing moles are not new.
Medical reports dating back more than a decade have documented significant pigment and mole changes following its use.
A 2011 report published in the British Journal of Dermatology, for example, described a woman whose existing moles changed and new moles appeared following Melanotan-II use. One changing lesion was subsequently diagnosed as melanoma.
Other reports and reviews have described similar changes in melanocytic naevi (moles) and cases in which melanoma was diagnosed following Melanotan use.
These cases do not prove that Melanotan-II caused the melanomas.
What they do show is that significant changes to moles and pigmentation have been observed following Melanotan use. The long-term safety of unregulated Melanotan-II use is also not well established.
New or changing mole: For someone who has used Melanotan-II, the practical message is straightforward: do not dismiss a new or changing mole simply because you think the change is an expected effect of the product.
Does Melanotan-II protect your skin from UV damage?
No tan should be considered adequate protection against UV radiation.
The Therapeutic Goods Administration (TGA) advises that artificially increasing skin pigmentation with melanotan does not protect the skin from UV exposure in the way appropriate sun protection does.
This is particularly important if Melanotan-II is being used alongside deliberate tanning.
A darker appearance does not remove the need for sun protection.
What other side effects are associated with Melanotan?
The TGA has warned that tanning products containing melanotan may cause serious health problems.
Reported effects include:
- headache
- nausea and vomiting
- loss of appetite
- facial flushing or redness
- increased moles and freckles.
The TGA has also reported more serious adverse effects associated with Melanotan-II, including kidney dysfunction and swelling of the brain.
There is an additional concern with products purchased through unregulated sources. Because these products have not been assessed by the TGA for quality and safety, there may be uncertainty about what they contain, their strength, their quality and whether the ingredients listed on the label are accurate.
I've used Melanotan-II. What should I do?
If you have used Melanotan-II, a tanning injection, nasal tanning spray or another product containing melanotan, the TGA recommends stopping use and speaking with a health professional.
If you are concerned about changes to your skin:
1.
Tell your doctor that you have used Melanotan-II. This information can be helpful when assessing changes in your skin.
2.
Have new or changing moles assessed. This is particularly important if a spot is changing rapidly or looks noticeably different from your other moles.
3.
Bring previous photographs if you have them. Older photographs can sometimes help your doctor understand whether and how a spot has changed.
4.
Avoid deliberate tanning and continue appropriate sun protection. A tan produced by Melanotan-II should not be considered protection against UV radiation.
There is no reason to feel embarrassed about discussing Melanotan-II use with your doctor. Providing an accurate history helps your doctor assess your skin with the appropriate clinical context.
Which mole changes should I have checked?
Not every mole change is melanoma and Melanotan-II can itself affect pigmentation. It is still important not to assume that a changing spot is harmless.
Arrange a medical assessment if you notice:
- a new or unusual looking mole
- a mole changing in size, shape or colour
- a spot that looks noticeably different from your other moles
- rapid darkening or growth
- multiple colours within a spot
- bleeding, crusting, itching or tenderness
- a sudden increase in new or changing moles
- any spot that concerns you.
One useful concept is the "ugly duckling" sign. Most of a person's moles tend to share certain characteristics. A mole that looks noticeably different from the others may warrant closer assessment.
You do not need to decide for yourself whether a changing spot is suspicious before seeing a doctor. If something has changed or concerns you, having it assessed is appropriate.
Skin assessment after Melanotan-II use
If you have used Melanotan-II and noticed changes in your moles, a skin assessment allows your doctor to examine those changes and consider them in the context of your individual skin cancer risk.
At Solvera Skin Cancer Institute in Norwest, skin assessments can include examination of individual lesions and where clinically appropriate, dermoscopy.
For some patients, including those with many moles or where monitoring change over time may be clinically useful, total body photography may also be considered. Your doctor can advise whether this is appropriate for you.
The most important thing is to be open about what you have used and what changes you have noticed. There is no judgement. The information simply helps your doctor understand the clinical picture and determine whether any areas require further assessment.
Concerned about a new or changing mole?
If you have used Melanotan-II or another tanning peptide and have noticed a new, changing or unusual spot, consider arranging a skin assessment.
You can book a skin check with Solvera Skin Cancer Institute in Norwest or speak with your usual doctor about your concerns.
Book a skin cancer check
Medically reviewed by: Dr Tim Scrivener, MBBS, FRACGP, MMed (Skin Cancer)
Last reviewed: September 2026
References:
- ABC News. Abnormal moles seen developing in patients chasing perfect suntan by using peptide melanotan-II. 5 June 2026.
- Therapeutic Goods Administration. Don't risk using tanning products containing melanotan. Australian Government.
- Therapeutic Goods Administration. Individual issued 27 infringement notices for allegedly supplying Melanotan II. 21 May 2026.
- Paurobally D, Jason F, Dezfoulian B, Nikkels AF. Melanotan-associated melanoma. British Journal of Dermatology. 2011;164(6):1403–1405.
- Habbema L, Halk AB, Neumann M, Bergman W. Risks of unregulated use of alpha-melanocyte-stimulating hormone analogues: a review. International Journal of Dermatology. 2017;56:975–980.
- Cancer Council Australia. Tanning. National Cancer Prevention Policy.
