Side-by-side · Research reference
Melanotan-IIvsMOTS-c
Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.
APhase 1Reviewed9/43 cited
BAnimal-StrongReviewed16/68 cited
Melanotan-II
MC1R + MC4R agonist · Tanning + sexual response
SQ · Abdomen · Loading 5–7 days, then maintenance
MOTS-c
Mitokine · Mitochondria-Encoded
SQ · Variable · 2–3×/week
01Mechanism of Action
Parameter
Melanotan-II
MOTS-c
Primary target
MC1R (skin) + MC3R + MC4R (CNS sexual / appetite)Dorr 1996
Mitochondrial 12S rRNA sORF → folate-AICAR-AMPK axisLee 2015
Pathway
MC1R agonism → melanocyte tyrosinase → eumelanin synthesis. MC4R → autonomic sexual arousal centresDorr 1996Simerly 2023
Downstream effect
Skin darkening, photo-protection, increased sexual desire / spontaneous erectionDorr 1996
Enhanced fatty acid oxidation, GLUT4-mediated glucose uptake, mitochondrial bioenergetics, anti-inflammationLee 2015
Origin
Cyclic 7-AA modified α-MSH analog; designed at University of ArizonaDorr 1996
Endogenous 16-AA mitokine; mtDNA-encoded; declines with age; upregulated by exerciseReynolds 2021
Antibody development
—
—
02Dosage Protocols
Parameter
Melanotan-II
MOTS-c
Maintenance
0.5–1.0 mg 1–2×/week
After visible tan develops; supports with UV exposure.
—
Frequency
Daily during loading; 1–2× per week maintenance
2–3× per week
Short half-life may necessitate more frequent dosing for saturation.
Lower / starter dose
0.1 mg / day
Conservative starter — assess tolerability for nausea.
2.5–5 mg / week
Recommended due to limited human data.
Evidence basis
Phase 1 + anecdotalDorr 1996
Animal + anecdotalLee 2015Reynolds 2021A first-in-human phase 1 study 2021
Phase 1a/1b CB4211 analog trial completed 2021; no native MOTS-c RCT published.
Duration
8–12 weeks per cycle
4–12 weeks (experimental)
Optimal cycle length unknown.
Reconstitution
Bacteriostatic water; protect from light
Bacteriostatic water, 1–2 mL
10 mg/mL at 1 mL.
Timing
Evening preferred (24h tan-development cycle)
Pre-workout or fasted state preferred
Activity-context amplifies AMPK response.
Half-life
~1 hour plasma; effects on melanocytes persist days
Minutes to hours (estimated)
Systemically unstable; native MOTS-c PK in humans not fully characterised.
Standard dose
—
5–10 mg / weekLee 2015
Experimental, extrapolated from animal data. No human RCT-derived dose.
03Metabolic / Fat Loss Evidence
Parameter
Melanotan-II
MOTS-c
Primary fat target
—
Diet-induced / metabolic obesity; systemic fat utilization
Quantified reduction
—
Significant HFD fat gain ↓Lee 2015
Murine models, dose-dependent (5 & 15 mg/kg).
IGF-1 impact
—
No direct IGF-1 pathway; AMPK-mediated
Effect on lean mass
—
High dose significantly ↑ lean mass in mice
Triglycerides
—
AMPK-driven FA oxidation suggests TG benefit (not directly measured)
Effect reversibility
—
Unknown — no long-term follow-up data
Key publication
—
Lee Cell Metab 2015 · Reynolds Nat Commun 2021 · Kim Cell Metab 2018Lee 2015Reynolds 2021Kim 2018
04Side Effects & Safety
Parameter
Melanotan-II
MOTS-c
Nausea
Common, especially loading phase
—
Flushing
Common transient
—
Increased mole / freckle pigmentation
Existing moles darken; new lesions possible
—
Melanoma risk
Theoretical concern — increased melanocyte activity; CAUTION in melanoma history
—
Appetite suppression
MC4R-mediated; mild
—
Pregnancy / OB
Contraindicated
Avoid — insufficient safety data
Injection site reaction
—
Mild irritation (reported)
Fluid retention / Edema
—
Not reported
Cardiovascular
—
Heart palpitations (anecdotal); cardiac hypertrophy reversed in diabetic rats
Cancer risk
—
Contradictory data — some models suggest pro-proliferative effects
CNS / Neurological
—
Insomnia, headache (anecdotal reports)
GI symptoms
—
Nausea, stomach discomfort (reported)
Antibody formation
—
No data (no long-term human trials)
Evidence quality
—
Phase 1 analog (CB4211); preclinical; anecdotal humanA first-in-human phase 1 study 2021
Absolute Contraindications
Melanotan-II
- ·History of melanoma or atypical mole syndrome
- ·Pregnancy / breastfeeding
- ·Active uncontrolled hypertension
MOTS-c
- ·Pregnancy / breastfeeding (insufficient data)
Relative Contraindications
Melanotan-II
- ·Significant freckling / dysplastic nevus
- ·Personal or family melanoma history
MOTS-c
- ·Active cancer or cancer predisposition
- ·AMPK pathway deficiency (efficacy nullified)
- ·Use with cancer-promoting medications (theoretical)
05Administration Protocol
Parameter
Melanotan-II
MOTS-c
1. Reconstitution
Add 2 mL bacteriostatic water to 10 mg vial → 5 mg/mL = 500 mcg per 0.1 mL. Light-protected.
Add 1–2 mL bacteriostatic water. At 10 mg/vial, 1 mL gives 10 mg/mL concentration. Roll gently to dissolve.
2. Injection site
SQ — abdomen. Rotate sites.
Subcutaneous — abdomen, thigh, or deltoid. Rotate sites to avoid lipohypertrophy. Pinch fat layer.
3. Timing
Evening preferred. UV exposure (sunlight or tanning bed) helps develop tan.
Pre-workout or fasted state preferred — metabolic context amplifies AMPK response. 2–3× per week.
4. Storage
Lyophilised: refrigerate, light-protected. Reconstituted: refrigerate ≤30 days.
Lyophilised: room temp, protected from light. Reconstituted: refrigerate, use within 21–30 days. Short systemic stability.
5. Needle
29–31G insulin syringe.
27–31G insulin syringe. Short needle (4–6 mm) for SQ delivery. Clean technique mandatory.
06Stack Synergy
Melanotan-II
— no documented stacks
MOTS-c
+ Ipamorelin
ModerateMOTS-c activates AMPK/PGC-1α for mitochondrial efficiency and fatty acid oxidation; ipamorelin stimulates GH for anabolic recovery and sleep depth. Pathways are complementary — MOTS-c handles metabolic flexibility and glucose handling while ipamorelin drives recovery and body recomposition through GH. Theoretical synergy is high; clinical data is lacking.
- MOTS-c
- 5 mg SQ · pre-workout (2–3×/wk)
- Ipamorelin
- 200–300 mcg SQ · pre-sleep (daily)
- Primary benefit
- Metabolic flexibility + GH recovery + ROS reduction