Melanotan-I after 4 days: quite pleased with the results

[TooBigtoFail]

I took MT1 for a 2-month stretch before I had to quit. Brown spots and freckles were appearing all over. My skin did tan, and nothing else went wrong. Now my dermatologist has a tougher job because of it.

 

[BlueDog55]

ambot88 said:

That's fascinating! It both unnerves me and draws me in. My girlfriend gave it a go and reported diarrhea along with a massive spike in libido - did anything like that happen for you?

Sorry, no disrespect intended, but when I read the bit in your post about "caused diarrhea and extreme libido" I cracked up laughing... that is honestly the last pairing anyone here would sign up for... Hey sweetie, come over here, kiss...kiss, oh hold on... and then sprinting to the toilet... sorry, I know I'm giggling like a child over this, it just struck me that way...

 

[sheilarae74]

PAPoots said:

2boxers said:

PAPoots said:

Were it not for how frequently nausea hits and the unplanned erections, I could see myself giving it a try. At 55 and getting on in years, I'd rather not have the freckles I already have turn darker and end up resembling liver spots, making me seem older than my actual age. A full kit probably isn't something I'd go for. Possibly a single bottle come springtime at a really low dose. For the libido side of things, Tadalafil does the job well enough.

The subject she's discussing is MT1, whereas the one you're bringing up is MT2.

MT1's strength is somewhat reduced. The risks and side effects remain identical, only at a lesser degree.



View attachment 10195



Melanotan 1 vs 2: Safety vs Potency (2026) | The Peptide Catalog



MT-1 has been studied by the FDA; MT-2 produces a tan more quickly, yet comes with a greater burden of side effects. A complete breakdown covering tanning, sexual effects, and safety.

View attachment 10196


thepeptidecatalog.com



View attachment 10197



The Truth About Melanotan: Tanning Peptide or More?



Wondering about Melanotan? Find out how this peptide functions for tanning, metabolism, libido, and beyond. See how Melanotan I & II differ, along with dosing advice, advantages, and safety factors.

View attachment 10198


www.revitalyzemd.com

Common Side Effects:

• Nausea (dose-dependent)
  
• Facial flushing
  
• Increased libido
  
• Long-term pigmentation changes
  
• Darkening of moles or freckles (monitor with provider)

Contraindications: Not for individuals with a history of melanoma or skin cancer.



View attachment 10199



Melanotan 1: Benefits, Dosage & Side Effects



Dig into the scientific research on the Melanotan 1 peptide and discover its advantages, suggested dosing, and possible adverse effects.

Image unavailable


jaycampbell.com

Yet, staying true to my trademark of complete and candid openness, I feel I should pass along what others have described:

• Possible formation of new moles and darkening of existing moles with the UNREGULATED use of Melanotan I (i.e. poor peptide quality, although some people report that moles and freckles fade away after discontinuing use of Melanotan I)
  
• The Therapeutic Goods Administration (TGA) of Australia: “Side-effects include darkened skin, increased moles and freckles, nausea, vomiting, loss of appetite, flushing of the face, involuntary stretching and yawning, and spontaneous erections.”
  
• “Patchy loss of pigmentation” following 50 mg of Melanotan I used over two months (a CLEAR mis-use of the peptide)
  
• One individual case report of a 23-year-old man developing malignant melanoma (although this comprehensive safety report examining multiple studies failed to find a definitive link)

Within the pages of Peptide Protocols (Vol. 1), Dr. William Seeds lays out a few highly particular situations in which Melanotan 1 ought not to be used:

• Do not use if there is a personal or family history of melanoma or non-melanoma skin cancer
  
• Melanocortins may increase blood pressure. Use with caution if hypertension is present
  
• It is NOT recommended to use a melanocortin agonist concurrently with a PDE5 inhibitor in men due to risk of priapism

As far as I'm concerned, if I weren't already stacking other peptides that carry their own side effects, I'd give a single vial a shot at a very low dose. For instance, Cagri and Reta are already capable of bringing on the occasional nausea. I already have tadalafil for the.... So, I wouldn't want to stack side effects.

Most of the legit peps have side effects that affect some more than others. I can't take Tesa at any dose without getting CPS in both hands.

That's rough. Skin cancer took my mom.

 

[PAPoots]

I'm wondering whether those who experienced side effects ramped up their dose too quickly, or began at a dose that was already too high.

 

[JourneyToPerfection]

I just picked up an MT1 kit and reading this has me super pumped to give it a go

A couple of questions

• Does tanning only happen in areas that see sun?
  
• I use tret cream so I'm really careful and always put sunblock on my face — any idea whether heavy sunblock would change how my face tans?

 

[CNCCurrency]

JourneyToPerfection said:

I just picked up an MT1 kit and reading this has me super pumped to give it a go

A couple of questions

• Does tanning only happen in areas that see sun?
  
• I use tret cream so I'm really careful and always put sunblock on my face — any idea whether heavy sunblock would change how my face tans?

I have, and despite applying sunscreen my face still developed an even tan. All that's needed is for your body to begin releasing melanin, and mt 1 keeps that release going for a longer period.

 

[Mimsy]

JourneyToPerfection said:

I just picked up an MT1 kit and reading this has me super pumped to give it a go

A couple of questions

• Does tanning only happen in areas that see sun?
  
• I use tret cream so I'm really careful and always put sunblock on my face — any idea whether heavy sunblock would change how my face tans?

Anyone here given it a go? How are things working out for you?

 

[FarmgirlRebel]

Okay...a bit of time has passed. Here's where I'm at: the color keeps building. Yes, I'm out in the sun, but I'm not doing any laying out, and I've seen that my legs — which barely catch any sun — have shifted a shade or 2 darker in their base tone too.

I'd read that this tends to happen for folks with olive skin, and in my case that's exactly how it played out. What used to be a "sun kissed" effect has now become a proper tan .

As far as age spots go, I haven't seen any increase, and no new spots have shown up either. One thing I did see: a beauty mark I already had became darker...Freckles aren't really something I have, so I can't say anything about those, and no new freckles appeared.

 

[Wenjo]

Such1943 said:

MT1, .5mg 2x a day, shirtless walks of about 2 miles each. Stopping after 1 vial...

I've been wanting to give MT1 a go for the longest time, but at the same time I spend a lot of time outside, and the worry has always been either burning or ending up overly tanned and looking ridiculous

 

[JP.MOTM]

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

 

[FarmgirlRebel]

JP.MOTM said:

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

That's interesting. When it comes to MT1, what I've gone through is a tan that's uniform everywhere, with zero uneven spots...though it could just be because of how my skin is naturally toned? Someone with a lighter complexion might end up seeing something totally different

 

[Vriende]

FarmgirlRebel said:

JP.MOTM said:

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

That's interesting. When it comes to MT1, what I've gone through is a tan that's uniform everywhere, with zero uneven spots...though it could just be because of how my skin is naturally toned? Someone with a lighter complexion might end up seeing something totally different

Based on the accounts I've come across from other users, uneven patches and getting an unpleasant, excessively dark tan seem to be more common with MT2.

There are plenty of good reasons to be cautious and stay with MT1

 

[Vriende]

JP.MOTM said:

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

Thank you for putting together that summary and for pointing to where your data comes from.

It's refreshing — so many people on here just dump polished AI-generated text without ever saying it's AI or giving any sources.

Appreciate it!

 

[JourneyToPerfection]

Mimsy said:

JourneyToPerfection said:

I just picked up an MT1 kit and reading this has me super pumped to give it a go

A couple of questions

• Does tanning only happen in areas that see sun?
  
• I use tret cream so I'm really careful and always put sunblock on my face — any idea whether heavy sunblock would change how my face tans?

Anyone here given it a go? How are things working out for you?

Still haven't gotten around to it my kit showed up a long time back, but it's winter over here in Aus — and while that does mean it's a bit less stupidly hot than usual, I still haven't had a solid week or two of sun that I could soak up with MT1 in my system

 

[JP.MOTM]

FarmgirlRebel said:

JP.MOTM said:

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

That's interesting. When it comes to MT1, what I've gone through is a tan that's uniform everywhere, with zero uneven spots...though it could just be because of how my skin is naturally toned? Someone with a lighter complexion might end up seeing something totally different

Great to hear it's working out! Have you also been exposing most of your body to the sun? Or did it darken uniformly even with no sun at all?

 

[JP.MOTM]

Vriende said:

FarmgirlRebel said:

JP.MOTM said:

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

That's interesting. When it comes to MT1, what I've gone through is a tan that's uniform everywhere, with zero uneven spots...though it could just be because of how my skin is naturally toned? Someone with a lighter complexion might end up seeing something totally different

Based on the accounts I've come across from other users, uneven patches and getting an unpleasant, excessively dark tan seem to be more common with MT2.

There are plenty of good reasons to be cautious and stay with MT1

Fascinating! Yeah, the evidence base isn't exactly solid (except for the MT-1 approval data). On top of that, with the grey market it's tough to tell whether people are mixing up MT1 and MT2 by accident. They just buy "melanotan" and guess which one it is. Or the vendor mislabels it, etc. Mislabelling is probably rarer these days given more testing, but even a few years back, testing was nowhere near as widespread.

Personally I've only ever run MT-2, though I might try MT-1 for the sake of science! My own experience has been excellent though — as someone who's a naturally very pale ginger, it's been a complete transformation.

Injecting 250-500mcg before bed on most nights (so I sleep through the nausea). Works out to roughly 4x per week on average.

Vriende said:

JP.MOTM said:

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

Thank you for putting together that summary and for pointing to where your data comes from.

It's refreshing — so many people on here just dump polished AI-generated text without ever saying it's AI or giving any sources.

Appreciate it!

Thanks! Yeah, I'm with you — now that AI is everywhere, anyone can sound smart. Full transparency: I do use AI, but not the way most people do. I built a crawler bot that runs nightly, hunting down all the latest DOI numbers for research papers matching keywords I choose. It grabs the full papers when it can, then files them in my repository. When it can't get the full paper, it just records the abstract and tags everything by category. That's my launchpad for any topic I dig into. After that I use claude to query my data and compile a complete list of every DOI I can't access. That list gets pushed through connectors to Consensus and Ellicit — two AIs with access behind most journal paywalls — so they can actually pull full papers and trial data. Claude, ChatGPT and the like can't do this on their own; they'll only work from abstracts, which isn't good enough. So it's really a tool that gets me access and speeds up my research, not something that tells me how to think.

From there I form my own view, write my own fully referenced "master document" on a topic, and keep it current. All of that probably runs about £250/month, but I used to be a scientist (still am IMO) and I'm active in this field, so for me it's worth it. If I can be useful and share some info, I will. And as you say, I include my citations so people can check them and reach their own conclusions too, rather than just "trust me bro".

 

[FarmgirlRebel]

JP.MOTM said:

FarmgirlRebel said:

JP.MOTM said:

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

That's interesting. When it comes to MT1, what I've gone through is a tan that's uniform everywhere, with zero uneven spots...though it could just be because of how my skin is naturally toned? Someone with a lighter complexion might end up seeing something totally different

Great to hear it's working out! Have you also been exposing most of your body to the sun? Or did it darken uniformly even with no sun at all?

Because I ride horses frequently, I do spend time in the sun—especially my face, shoulders and arms—so those spots are clearly darkening. That said, my baseline tone on my legs and torso has also shifted slightly darker even without sun. It's not a tan yet, but it's just visible enough to notice.

 

[JourneyToPerfection]

FarmgirlRebel said:

JP.MOTM said:

FarmgirlRebel said:

JP.MOTM said:

Wanted to lay some of this out more clearly and share where I've landed.

Afamelanotide, which is the approved form of MT1, only hits the melanocortin 1 receptor (MC1R). With MT2, you're stimulating MC1R plus MC3, MC4 and MC5R, and those extra receptors are what drive the libido changes and the nausea/appetite stuff. None of that comes with MT1. On top of that, MT2 drives MC1R harder, and it will give you more even pigment/tan even when there's no UV involved. MT1 tends to go on patchier and can darken the face more in the absence of UV.

Over 8 or 10 years of MT1 trials and follow-ups, no melanoma risk increase showed up compared with controls. MT2 hasn't been put through that kind of testing. That doesn't make it less safe, it just means the answer isn't known, so there's some risk sitting there. The melanoma reports tied to MT2 are mostly case studies, and those are heavily confounded because the same people were also using sunbeds, which is a recognised melanoma risk on its own.

When skin is healthy, switching MC1R on looks protective. It produces eumelanin (the main melanin type responsible for skin pigmentation), which blocks UV physically and protects DNA from damage. It also boosts the cell's own DNA repair and antioxidant defences. And in mice, MC1R activation stopped melanoma from developing, while topical MT2 even made existing tumours shrink. That was an animal model, but it's still interesting.

Then there's a small 2023 study: turning this receptor on inside melanoma cells that already existed dialled down the signal that recruits immune T-cells into the tumour, so the cancer concealed itself better and grew. Honestly I'm not sure how to square that one. My read is that the mouse data plus the clinical data on MT1 carry far more weight than this mechanistic study.

So IMO, MT1 has some pretty decent data behind it, MT2 not loads. Still, the risks look overstated to me (though nothing is safe).

The data I looked at:

Habbema L, et al. Risks of unregulated use of alpha-MSH analogues: a review. Int J Dermatol 2017.

Hjuler KF, Lorentzen HF. Melanoma associated with Melanotan-II. Dermatology 2013. (See also Mallalieu 2021; Alsabbagh 2025, both UV-confounder-free.)

Chen S, et al. Palmitoylation-dependent activation of MC1R prevents melanomagenesis. Nature 2017. (Swope & Abdel-Malek, Int J Mol Sci 2018.)

Wu JC, et al. Topical MTII suppresses melanoma via PTEN / COX-2 (mouse). Int J Mol Sci 2020.

Cui Y, et al. MC1R signalling impairs T-cell infiltration to dampen antitumor immunity; high MC1R correlates with poorer prognosis. Nat Commun 2023.

Nelson ME, et al. Melanotan II systemic toxicity and rhabdomyolysis. Clin Toxicol 2012.

Böhm M, et al. Benefits and risks of chronic MC1R activation. JEADV 2024.

FDA CDER. Scenesse (afamelanotide) NDA 210797, Risk Assessment Review, 2019: no evidence of increased melanoma; EMA exposure up to 10 years; US follow-up minimum 8 years.

Minder EI, et al. Pharmacokinetics and pharmacodynamics of afamelanotide. Clin Pharmacokinet 2017. (Biolcati 2015; Homey 2025.)

That's interesting. When it comes to MT1, what I've gone through is a tan that's uniform everywhere, with zero uneven spots...though it could just be because of how my skin is naturally toned? Someone with a lighter complexion might end up seeing something totally different

Great to hear it's working out! Have you also been exposing most of your body to the sun? Or did it darken uniformly even with no sun at all?

Because I ride horses frequently, I do spend time in the sun—especially my face, shoulders and arms—so those spots are clearly darkening. That said, my baseline tone on my legs and torso has also shifted slightly darker even without sun. It's not a tan yet, but it's just visible enough to notice.

What's the situation like at this point? Over here in Australia the sun has returned (it's still winter, though that only sticks around for 6-8 weeks in these parts) and I've just injected my initial MT1 dose, which was 0.25mg

The face flushing hit me for roughly 10 minutes, and my cheeks are still warm, but I haven't noticed any nausea (thank goodness, since I absolutely hate nausea).

I'm about to spend half an hour lying next to the pool, and I'm really hoping I'll see the same level of change you got in 4 days!! That would make such a difference for my pale, vampire-esque look

 

[Indiana]

FarmgirlRebel said:

Alright! Melanotan I, day 4

Direct sun exposure stayed under 30 minutes, though I spent plenty of time outdoors being active.

The 1st photo was taken right after the initial injection.

The 2nd photo shows how things look 4 days afterward.

A deep, dark tan isn't what I'm after — I prefer a sunkissed appearance — so this outcome has me really satisfied, and there was no burning at all.

My skin is olive, and I'm 62 years old.

Neither picture includes makeup...I rarely bother with it unless I'm getting dressed up for an occasion.

That's great! This is exactly the outcome I'm aiming for.

 

[Indiana]

FarmgirlRebel said:

PAPoots said:

What weekly melanotan dose in mg is needed for tanning, and once you quit, does the color go away more quickly than usual?

I'm trying to figure out the number of vials required so I can have a light honey tan that carries me from June through September while getting very little sun.

So for week 1, my dose is 200mcg daily for 5 days. Then week 2, I move to 250 mcg on alternate days...for upkeep, 200-250mg twice weekly...I'll need to monitor how it progresses, since I've never researched this before.

I have to mention, by day 4 I've hit maintenance already...going darker isn't my goal, I was after a more sunkissed look...we'll see how it turns out. My skin is olive to start, and I tan pretty readily, though I usually get a minor burn on the first summer exposure. This time, no burn

Could a smaller dose still eventually produce the tan you're after? Since I'm not in a hurry to tan, I'd prefer to take less and just let it take more time to reach that point.