Melanotan II and 'tan maintenance': what the peptide scene gets wrong

What did @harrian_ actually say?

@harrian_ ran a self-described seven-day experiment using daily doses of Melanotan II (which he calls "Malano 10") and returned from vacation reporting visible tanning results. He says he noticed "a lot more golden or bronze" skin tone and credits the peptide as a success. He also mentions "a little bit more facial clarity" but appropriately caveats that he was on vacation and can't fully attribute that to the peptide. He plans to drop to once-weekly dosing to maintain his tan. The jellyfish encounter he jokes about is, notably, not a controlled variable in any meaningful sense.

To his credit, he keeps the claims relatively modest. He doesn't claim Melanotan II cured anything, reversed aging, or built muscle. He's describing cosmetic tanning, which is actually the most documented use of this compound in the research literature.

Does the science back this up?

On the core tanning claim, yes, the mechanism is real and studied. Melanotan II is a synthetic analogue of alpha-melanocyte-stimulating hormone (alpha-MSH). It binds melanocortin receptors, particularly MC1R, triggering increased melanin synthesis. That is not in dispute.

Barnetson et al. (2006, Journal of Investigative Dermatology) showed that afamelanotide, a related MC1R agonist, produced measurable pigmentation in human subjects. King et al. (2009, British Journal of Dermatology) confirmed that Melanotan II specifically does increase skin pigmentation in clinical settings. So the biological pathway @harrian_ is exploiting is legitimate.

The part that gets complicated is the safety profile. Melanotan II is not approved by the FDA or any major regulatory body for cosmetic tanning. It has documented side effects including nausea, facial flushing, spontaneous erections, and more seriously, case reports of atypical mole changes that have raised dermatologist concerns about melanoma risk when used without supervision (Langan et al., 2020, BMJ Case Reports).

What did they get wrong (or right)?

He got the tanning mechanism right. The peptide works the way he's implying it works, and his results are consistent with what the literature predicts. The caveat on facial clarity was genuinely good epistemic hygiene. Not many TikTok creators admit they can't attribute a result to their experiment. That deserves credit.

What he didn't address, and what viewers likely won't ask, is the regulatory and safety context. Melanotan II is not a tested, approved product. The sources selling it for injection are unregulated, purity is variable, and dosing is entirely self-directed. The shift from daily to weekly maintenance dosing sounds systematic, but there is no published clinical protocol for recreational cosmetic Melanotan II use because none exists.

He also didn't mention that Melanotan II binds MC3R and MC4R in addition to MC1R, which is why the side effect profile goes well beyond skin. That's not a minor footnote. Spontaneous erections and nausea were common enough in early trials that they affected study completion rates (Wessells et al., 2000, Journal of Urology).

What should you actually know?

Melanotan II works as a tanning agent by a real, studied mechanism. That part is not pseudoscience. But "it works" and "it's safe to use without supervision" are two different statements, and this video only really addresses the first.

The bigger issue is the supply chain. Melanotan II sold for recreational use comes from unregulated sources. You don't know the purity, concentration, or sterility of what you're injecting. Compounded peptides from regulated telehealth pharmacies are subject to USP standards. Random online sources are not, and the product is frequently mislabeled or contaminated (Lippi et al., 2018, Clinical Chemistry and Laboratory Medicine).

If you're interested in peptide-based approaches to skin health or recovery, a licensed provider can walk through what's actually available through legal, regulated channels. Self-experimenting with unregulated injectable peptides based on a TikTok results video is a different category of decision entirely.