The Peptide Reference
The Peptide Reference
References
Reference/Synthetic peptide analog

Melanotan I

Melanocortin Receptor Agonist

Mechanistic
research use only

Synthetic analog of α-MSH that selectively targets MC1 receptors for melanin stimulation. FDA-approved as SCENESSE implant for erythropoietic protoporphyria (EPP). Research-grade injectable form enables flexible dosing versus the implant version.

Precise dosing control with rapid tanning onsetFlexible home administration unlike implant versionVisible tanning within 1-2 weeks with UV exposureEnhanced photoprotection through increased melanin
01

Overview

Synthetic analog of α-MSH that selectively targets MC1 receptors for melanin stimulation. FDA-approved as SCENESSE implant for erythropoietic protoporphyria (EPP). Research-grade injectable form enables flexible dosing versus the implant version.

Subcutaneous injection delivers peptide directly into systemic circulation. Selectively activates MC1R receptors to stimulate melanin production. Short half-life of approximately 30 minutes necessitates multiple daily dosing for sustained effect.

Evidence profilederived from 3 references
D
Mechanistic
Strongest design among the references on this page. Grade and effect size are separate facts and are never merged into one score.
02

Research indications

What the compound has been studied for, grouped by body system. Effect size is the reported magnitude where it was measured — not a recommendation.

Skin Health3
Enhanced Tanning Response

Stimulates melanin for deeper, longer-lasting tans with reduced UV requirements

Large
Photoprotection

Increased melanin density provides natural UV protection and reduces sunburn

Large
Even Pigmentation

Promotes uniform melanin distribution minimizing patchy tanning

Moderate
Medical Applications1
Erythropoietic Protoporphyria

FDA-approved indication for SCENESSE implant

Large
i

A large effect in a weak study and a small effect in a strong one are different things. Effect size is never evidence of use in people.

Quick factsreference only
Class
Synthetic peptide analog
Molecular weight
1646.88 Da
Half-life
~30 min
Typical dose
Loading: 0.25-0.5mg daily; Maintenance: 0.25-0.5mg 2-3x weekly
Frequency
Loading phase: 1-2x daily for 1-2 weeks, then maintenance 2-3x weekly
Cycle length
2-4 week loading phase, then ongoing maintenance as needed
Storage
Refrigerate reconstituted solution at 2-8°C, use within 4 weeks
03

Molecular data

Type
Synthetic peptide analog
Molecular weight
1646.88 Da
Half-life
30 min
04

Dosing reference

Doses reported in the literature and by suppliers. These are a record of what has been used in research — reference, never instruction.

ContextRouteAmountFrequency
Loading phaseSubcutaneous0.25-0.5mg1-2x daily for 1-2 weeks
MaintenanceSubcutaneous0.25-0.5mg2-3x weekly
Standard dosingIntranasal0.5mg per spray2-3x daily
05

Interactions

Melanotan II

Overlapping mechanisms; avoid combining

avoid
UV Exposure

Reduces required UV dose by approximately 50%

synergistic
Beta-Carotene

Provides additional photoprotection

compatible
Tretinoin/Retinoids

Retinoids increase photosensitivity; monitor skin reactions

monitor
Photosensitizing Medications

Enhanced monitoring recommended

monitor
06

Quality checklist

  • Third-party HPLC testing confirming >98% purity
  • Proper lyophilized powder storage
  • Clear, colorless reconstitution
  • Minimal side effects profile
  • !Check expiration dates
  • ×Pre-mixed liquid solutions (degrade rapidly)
  • ×Cloudy or discolored solution
07

What to expect

Days 1-3Possible mild nausea, facial flushing, reduced appetite
Days 3-7Initial skin darkening, increased mole/freckle pigmentation
Week 1-2Noticeable tanning with minimal UV exposure
Week 2-4Peak effects, maintained pigmentation with reduced frequency
08

Safety

Commonly reported4
  • Mild nausea
  • Facial flushing
  • Reduced appetite
  • Increased mole/freckle pigmentation
Stop and seek advice5
  • Severe nausea/vomiting lasting >24 hours
  • Rapid concerning mole/freckle changes
  • Injection site infection signs
  • Unusual skin reactions
  • Allergic reaction symptoms
09

FAQ

Is Melanotan I more selective than Melanotan II?

Yes. Melanotan I is more selective for MC1R (melanin production) and less active on MC4R (sexual function, appetite). This means MT-I causes tanning without the strong appetite suppression or sexual side effects of MT-II, making it better if tanning is the only goal.

How fast will I see results from Melanotan I?

Initial skin darkening appears within 3-7 days with UV exposure. Peak tanning is visible by week 2-4 with consistent low-dose UV tanning. The combination of MT-I plus 50% less UV exposure than normal achieves deep tans much faster than sun exposure alone.

Can I use Melanotan I without any UV exposure?

Melanotan I stimulates melanin production, so some pigment develops without sun exposure. However, UV exposure significantly enhances the effect—ideally low-dose tanning bed or sun exposure 1-2 hours after injection maximizes the tanning response.

Does Melanotan I cause mole changes like Melanotan II?

Less commonly than MT-II, but moles and freckles can darken and potentially enlarge with MT-I use. Regular skin monitoring via self-examination is important. The risk appears lower with MT-I than MT-II due to reduced MC3R/MC4R activation.

10

References

  1. 1
    Melanocortin Receptor Binding Study
    PubMed · 1997

    Characterized MC1R selectivity

  2. 2
    Pharmacokinetics Injectable MT-I
    PubMed · 1997

    Established half-life and bioavailability parameters

  3. 3
    MT-I Photoprotection Study
    PubMed · 2004

    Demonstrated significant photoprotection effects

For research use only. Nothing on this page is medical advice, and no number here is a recommendation to dose.