Melanotan I: Reference Overview and Reconstitution Notes

Melanotan I (afamelanotide) is a man-made peptide (a short chain of protein building blocks) that activates a specific protein on skin cells called the melanocortin-1 receptor (MC1R). It belongs to a group of research compounds studied for skin pigment and light protection. A prescription form of this compound is FDA-approved for a rare light-sensitivity disorder called erythropoietic protoporphyria.

Melanotan I

What it is

Melanotan I, also known by its scientific name afamelanotide, is a man-made 13 amino acid peptide (a short chain of 13 protein building blocks). It is designed to look and act like a natural body hormone called alpha-melanocyte stimulating hormone (alpha-MSH), which signals skin cells to produce pigment. Melanotan I targets a specific protein called the melanocortin-1 receptor (MC1R), which works like an "on switch" for dark pigment production in skin cells.

Research context and categorization

Melanotan I is grouped with research compounds studied for skin pigment and light protection. Because it selectively activates MC1R (that "on switch" for dark pigment), researchers study it in the context of increasing eumelanin (the dark brown and black pigment) in the outer layer of skin. Think of eumelanin as the skin's natural sunshade. Understanding how to increase it is one area scientists are actively exploring.

Clinical Applications and Research

In its FDA-approved prescription form (afamelanotide, sold as Scenesse by Clinuvel Pharmaceuticals), this compound is used to reduce painful reactions to light in people with erythropoietic protoporphyria (EPP). EPP is a rare inherited condition where a chemical build-up in the body makes the skin extremely sensitive to light, causing severe pain even from brief exposure.

Researchers also study the compound in connection with other conditions, though none of these are approved uses:

• Vitiligo (a condition where patches of skin lose their pigment, often studied alongside a type of UV light therapy called narrowband UV-B phototherapy)
• Polymorphous light eruption (a common rash that appears after sun exposure)
• Solar urticaria (hives triggered by sunlight)

These are not confirmed or approved benefits. As a raw freeze-dried research powder, Melanotan I is not the same as the approved prescription product and is not approved for human use or compounding.

Key point: While the prescription implant form (Scenesse) is FDA-approved to treat EPP, raw research-grade Melanotan I powder is not approved for human use or cosmetic tanning.

Status

• Regulatory status: FDA-approved for a specific use (afamelanotide / Scenesse, approved October 2019 for painful light reactions in erythropoietic protoporphyria). Raw research-grade Melanotan I powder is for research use only and is not FDA-approved for human use. There is no FDA-approved cosmetic tanning indication.
• Sport status: Listed as prohibited under the WADA Prohibited List (the global anti-doping rules used in sport). It falls under Section S2, which covers peptide hormones and similar compounds. It can be detected in urine and blood using a lab method called LC-MS/MS (a precise chemical identification technique).

Reconstitution notes (general)

Lyophilized peptides are compounds that have been freeze-dried into a powder, similar to instant coffee. They are prepared by adding bacteriostatic water (water that contains a small preservative to stop bacteria from growing) to the powder in the vial. The concentration of the resulting solution is simply the milligrams in the vial divided by the millilitres of water added.

For example, 10 mg of powder mixed with 2 mL of water gives a concentration of 5 mg/mL. A reconstitution calculator is available at peptide calculator to work out the concentration for any vial size and water volume.

Dilution and handling notes (compound-specific)

The FDA-approved product, Scenesse, is a solid implant placed under the skin and is not mixed with water. The notes below apply only to lyophilized Melanotan I powder sold for research reference, not to the approved implant.

Recommended Ratios

Reference material commonly describes a 10 mg vial mixed with 1 to 3 mL of bacteriostatic water, most often 2 mL. A 1:1 volume ratio (for example, 10 mL of water into a 10 mg vial, giving 1 mg/mL) is also documented.

Adding more water makes a more dilute solution that is easier to measure accurately. Less water gives a smaller total volume at a higher concentration. The 2 mL / 5 mg/mL point is often described as a practical middle ground that works well with standard graduated syringes.

Mixing and Dissolution

Melanotan I generally dissolves easily. Reports describe the freeze-dried powder going into solution within a minute or two, producing a clear liquid that is colorless to faintly amber, with no visible particles.

Unlike some concentrated peptides that can turn cloudy or gel, Melanotan I at these ratios usually stays clear. A cloudy or particulate result is typically a sign of a handling problem, not normal behavior.

The standard technique for safe dissolution includes:

1. Run the water slowly down the inside glass wall of the vial rather than squirting it directly onto the powder.
2. Swirl the vial gently. Do not shake, as shaking creates physical stress that can damage the peptide and produces foam that makes it hard to read the volume accurately.
3. If a faint haze or small white flecks appear at higher concentrations, place the vial in a refrigerator at 2 to 8 °C for a short time, then swirl again to help it finish dissolving.

This peptide is sensitive to light, heat, and rough handling. Keep both the dry powder and the mixed solution away from direct light at all times, and handle with care.

Handling and storage

Store the mixed solution in the refrigerator at 2 to 8 °C and keep it out of direct light. Write the mix date on the vial label so you can easily track its age.

Best practices for keeping the solution sterile and stable include:

• Wipe the rubber stopper with an alcohol prep pad before drawing from the vial, and let it air-dry.
• Keep reconstituted material refrigerated and use it within a four-week (roughly 28 day) window.
• Discard the vial if the contents turn cloudy or discolored, or if any floating particles appear.

Related reading

• Oxytocin
• Semaglutide
• Teriparatide
• How Reconstitution Works
• How Long Does a Reconstituted Vial Last?

Tools and supplies

• peptide calculator
• Bacteriostatic Water 30 ml
• Gansulin Metal Reusable Pen
• 3 ml Glass Cartridges (10-pack)
• Complete Starter Kit

Reminder: research and educational reference only. Preppin Peppers sells hardware and materials, not peptides. Not medical, dosing, or health advice, not evaluated by the FDA, and not intended for human or animal use.

Frequently asked questions

What is Melanotan I and how does it work?

Melanotan I (afamelanotide) is a synthetic 13-amino acid peptide designed to mimic alpha-MSH. It activates the melanocortin-1 receptor (MC1R) on skin cells, triggering eumelanin (dark pigment) production.

Is Melanotan I detectable in drug testing?

Yes, Melanotan I is listed as prohibited under WADA Section S2 (peptide hormones). It can be detected in urine and blood using LC-MS/MS, a precise chemical identification technique.

What is the regulatory status of Melanotan I?

The prescription implant form (Scenesse) is FDA-approved (October 2019) for erythropoietic protoporphyria. Raw research-grade powder is NOT FDA-approved for human use or cosmetic tanning.

What the research community gets wrong about Melanotan I

A few mix-ups show up again and again in bench notes and reference material. Getting these straight keeps your records clean and your samples usable.

• Melanotan I and Melanotan II are not the same peptide. Melanotan I (afamelanotide) is a 13 amino acid chain. Melanotan II is a shorter cyclic peptide with a different sequence. Copying handling numbers from one label to the other puts wrong reference data in your notebook.
• The raw research powder is not Scenesse. The FDA approved product is a solid implant placed under the skin, not a liquid you mix. Numbers written for the implant do not describe the freeze-dried powder in a vial, so do not treat them as the same material.
• A clear solution is one observation, not proof of concentration or purity. Melanotan I usually goes into solution as a clear, colorless to faintly amber liquid. That tells you it looks dissolved. It does not confirm how many milligrams are actually in the vial or that the peptide is intact.
• Light exposure is easy to underestimate. This peptide is sensitive to light and heat. Leaving vials sitting under bench lamps or near a window is a common way samples drift before anyone notices.
• Shaking does not speed things up. Shaking adds physical stress that can damage the peptide and makes foam that hides the true liquid level. A slow, gentle swirl reads more accurately and treats the sample better.

From our bench: When you reconstitute a Melanotan I vial, log the plain facts as you see them. Note the milligrams stated on the vial, the exact volume of bacteriostatic water you added, how long the powder took to fully clear, and the color of the finished liquid. If you have run the same vial size more than once, tell us whether the dissolution time and appearance held steady or varied. Record only what you actually measured, with no rounding to make it look neat.

Sources

1. Bacteriostatic Water for Injection, USP , FDA/DailyMed label (0.9% benzyl alcohol)
2. Duerkop et al., Biotechnol J 2018 , Impact of Cavitation, High Shear Stress and Air/Liquid Interfaces on Protein Aggregation
3. Sigma-Aldrich (Merck) , Handling and Storage Guidelines for Peptides and Proteins
4. Afamelanotide (Melanotan-1), PubChem CID 16197727, molecular formula C78H111N21O19
5. SCENESSE (afamelanotide) implant, FDA/DailyMed prescribing label