Melanotan I

What it is

Melanotan I is a synthetic version of alpha-melanocyte-stimulating hormone (alpha-MSH), the hormone that tells skin cells to make the dark pigment melanin. The licensed medicine afamelanotide (brand name Scenesse) is essentially this molecule, delivered as a slow-release implant under the skin.

It is a separate compound from Melanotan II, which is covered on its own page. MT-I is more selective for the receptor that drives tanning (MC1R). MT-II is less selective and hits other melanocortin receptors, which explains why MT-II is more associated with libido effects, nausea and appetite changes.

Scenesse is a prescription-only medicine given by specialist centres. The injectable vials sold online are unlicensed. In the UK, the medicines regulator (MHRA) has warned against buying and using unlicensed melanotan products.

History

Developed in the 1980s at the University of Arizona by Victor Hruby, Mac Hadley and colleagues as a sunless-tanning and sun-protection concept. Afamelanotide was developed commercially (now by Clinuvel) and approved in the EU in 2014 and in the US in 2019 for erythropoietic protoporphyria (EPP), a rare condition in which sunlight causes severe pain. Roughly 40 years old.

How it works

It activates melanocortin-1 receptors on pigment cells, which causes them to make more eumelanin, the brown-black pigment. Darker skin offers a little more protection from UV, but it does not make you immune to sunburn or skin cancer. In EPP, increased pigment helps people tolerate more light exposure.

Dosage

• Licensed use: Scenesse is a 16 mg implant placed under the skin by a clinician roughly every two months. That is a different delivery system from injected vials, so the numbers do not translate directly.
• Community use of injectable vials commonly reports about 0.25-1 mg per day during a loading phase, often combined with sun or sunbed exposure, then a maintenance dose a couple of times a week. These are anecdotal numbers.
• Starting low is a standard piece of advice, because nausea and flushing are dose dependent.

How it is taken

• Subcutaneous injection into belly fat with a 29-31G insulin syringe.
• Some people inject before bed to sleep through nausea or flushing.
• Tanning still needs some UV exposure, because the peptide alone makes limited difference to colour.

How to reconstitute

• For a 10 mg vial, adding 2 ml of bacteriostatic water gives 5 mg/ml. On a 1 ml (100-unit) insulin syringe, 5 units (0.05 ml) is 0.25 mg, 10 units is 0.5 mg and 20 units is 1 mg.
• Add water slowly down the vial wall, swirl gently, and do not shake.

How it should arrive

A sealed glass vial with a white to off-white lyophilised powder cake.

How it should look once reconstituted

A clear, colourless solution with no particles.

What to expect, and when

• Darkening typically becomes visible after a week or two of dosing, usually with some UV exposure.
• Freckles and moles may darken at the same time.
• Colour fades gradually after stopping, over weeks.

Side effects

• Nausea, especially early on or at higher doses.
• Facial flushing and warmth.
• Darkening of freckles and moles, and sometimes new moles appearing.
• Tiredness and yawning. Loss of appetite in some.
• Injection-site bruising or irritation.
• Spontaneous erections are a known effect, though weaker with MT-I than MT-II.

Risks

• Changes to moles and freckles can make it harder to spot a dangerous mole. Any mole that changes in shape, colour or size should be seen by a doctor, and regular skin checks matter more if you use melanotan.
• There is no long-term safety data in healthy people using it for cosmetic tanning. Scenesse has long-term monitoring data in EPP patients, but that is a different population and delivery.
• Unlicensed products can be mislabelled, contaminated or contain other melanotan variants. Products sold as MT-I have been found to contain different peptides.
• Tan from peptides plus sunbeds or strong sun still carries the full skin cancer risk from UV.
• People with a personal or family history of melanoma should not use it.

Potential gains

• Skin pigmentation, with modest photoprotective benefit.
• In EPP patients, more time tolerated in sunlight. That is the licensed benefit.
• Fewer side effects than MT-II for many users, because it is more selective, though that does not make it safe.

Other useful information

If you are considering melanotan for a tan, MT-I is generally regarded as the milder option compared with MT-II. If you have EPP, Scenesse through a specialist centre is the legitimate route. See the Melanotan II page for the libido-focused cousin.