Side-by-side · Research reference

Melanotan-IIvsVIP

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

APhase 1HUMAN-REVIEWED9/43 cited

BPhase 3HUMAN-REVIEWED9/42 cited

Melanotan-II

MC1R + MC4R agonist · Tanning + sexual response

0.25–1.0 mgPer doseDorr 1996

Phase 1Evidence levelDorr 1996

~1 hrHalf-life

SQ · Abdomen · Loading 5–7 days, then maintenance

VIP

Neuropeptide · VPAC1/VPAC2 Agonist · Emergency Use Authorization (COVID-19 ARDS)

IntravenousPrimary routeBrown 2023

ARDSLead indicationUdupa 2025

Phase 3Development stage

IV infusion · Inhaled (investigational)Brown 2023 Boesing 2022

01Mechanism of Action

Parameter

Melanotan-II

VIP

Primary target

MC1R (skin) + MC3R + MC4R (CNS sexual / appetite)Dorr 1996

VPAC1 and VPAC2 G-protein-coupled receptorsUdupa 2025

Pathway

MC1R agonism → melanocyte tyrosinase → eumelanin synthesis. MC4R → autonomic sexual arousal centresDorr 1996 Simerly 2023

VIP → VPAC1/VPAC2 activation → cAMP elevation → Pulmonary vasodilation + epithelial protection

Downstream effect

Skin darkening, photo-protection, increased sexual desire / spontaneous erectionDorr 1996

Anti-inflammatory cytokine modulation, alveolar-capillary membrane stabilization, pulmonary smooth muscle relaxation, reduced neutrophil infiltration

Feedback intact?

—

Yes — exogenous VIP acts as physiological agonist

Origin

Cyclic 7-AA modified α-MSH analog; designed at University of ArizonaDorr 1996

Endogenous 28-amino-acid neuropeptide; synthetic analogue (aviptadil) identical to natural VIP

Antibody development

—

02Dosage Protocols

Parameter

Melanotan-II

VIP

Loading phase

0.25–0.5 mg/day SQ × 5–7 daysDorr 1996

Builds up to visible tan.

—

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

—

Lower / starter dose

0.1 mg / day

Conservative starter — assess tolerability for nausea.

—

Evidence basis

Phase 1 + anecdotalDorr 1996

Phase 3 RCT (TESICO)Brown 2023

816-patient randomized controlled trial in COVID-19 ARDS.

Duration

8–12 weeks per cycle

—

Reconstitution

Bacteriostatic water; protect from light

Lyophilized powder reconstituted with sterile diluent per protocol

Timing

Evening preferred (24h tan-development cycle)

—

Half-life

~1 hour plasma; effects on melanocytes persist days

~2 minutes (plasma)

Rapid clearance necessitates continuous infusion.

Intravenous (ARDS protocol)

—

60–90 mcg/kg/day via continuous infusion

TESICO trial protocol for COVID-19 ARDS.

Infusion duration

—

12-hour continuous IV infusion dailyBrown 2023

Inhaled (investigational)

—

Variable dosing under clinical trial protocolsBoesing 2022

Delivered via nebulizer for direct pulmonary deposition.

Treatment duration

—

3–14 days (acute ARDS)

04Side Effects & Safety

Parameter

Melanotan-II

VIP

Nausea

Common, especially loading phase

—

Flushing

Common transient

—

Spontaneous erection

Common in men — MC4R cross-effectDorr 1996

—

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

—

Hypotension

—

Transient vasodilation-related blood pressure drop

Tachycardia

—

Reflex tachycardia secondary to vasodilation

Infusion site reactions

—

Erythema, phlebitis (IV administration)

GI symptoms

—

Nausea, diarrhea (VIP is endogenous GI peptide)

Overall tolerability

—

Well-tolerated in Phase 3 trials; adverse event profile comparable to placebo

Absolute Contraindications

Melanotan-II

·History of melanoma or atypical mole syndrome
·Pregnancy / breastfeeding
·Active uncontrolled hypertension

VIP

·Known hypersensitivity to aviptadil or formulation components

Relative Contraindications

Melanotan-II

·Significant freckling / dysplastic nevus
·Personal or family melanoma history

VIP

·Severe hypotension or shock states (monitor blood pressure)
·Pregnancy — insufficient safety data

05Administration Protocol

Parameter

Melanotan-II

VIP

1. Reconstitution

Add 2 mL bacteriostatic water to 10 mg vial → 5 mg/mL = 500 mcg per 0.1 mL. Light-protected.

Reconstitute lyophilized aviptadil powder with sterile diluent per manufacturer protocol. Inspect solution for particulates — should be clear and colorless.

2. Injection site

SQ — abdomen. Rotate sites.

Administer as continuous 12-hour intravenous infusion via central or peripheral line. Use infusion pump for precise dosing (60–90 mcg/kg/day divided over infusion duration).

3. Timing

Evening preferred. UV exposure (sunlight or tanning bed) helps develop tan.

Monitor blood pressure, heart rate, and oxygenation continuously during first infusion. Assess for hypotension and adjust infusion rate if needed.

4. Storage

Lyophilised: refrigerate, light-protected. Reconstituted: refrigerate ≤30 days.

Deliver via jet or mesh nebulizer per clinical trial protocol. Patient seated upright, normal tidal breathing for 10–15 minutes.

5. Needle

29–31G insulin syringe.

Store lyophilized powder at 2–8 °C, light-protected. Reconstituted solution: use immediately or within 24 hours if refrigerated.