Melanocortin signaling
MT-II is studied as a synthetic melanocortin receptor agonist.
Melanotan II (MT-II) BAC Water & Reconstitution Guide
Melanotan II (MT-II) is a synthetic cyclic heptapeptide analogue of α-melanocyte-stimulating hormone (α-MSH) that has been investigated for melanocortin-receptor activity, pigmentation, and other physiological effects. It remains an investigational compound rather than an FDA-approved human medicine.
Direct answer: There is no single universal BAC-water volume for Melanotan II. The appropriate mathematical volume depends on the quantity of compound in the vial and the target concentration. The examples on this page show concentration mathematics only and are not human dosing, administration, or treatment instructions.
Melanotan II Research Snapshot
Compound Melanotan II (MT-II)
Compound Class Synthetic cyclic heptapeptide
Research Category Melanocortin receptor research
Regulatory Status Not FDA-approved
Human Evidence Early/small clinical studies + ongoing investigation
Molecular Formula C50H69N15O9
Molecular Weight Approximately 1024.2 g/mol
CAS 121062-08-6
Last Scientifically Reviewed September 10, 2026
Melanotan II Molecular Research
How Much BAC Water for Melanotan II?
There is not one scientifically universal BAC-water volume for Melanotan II. The liquid volume selected for a research preparation determines the resulting concentration, while the total amount of Melanotan II represented by the vial remains unchanged.
For mathematical concentration calculations:
Concentration = Vial quantity ÷ Liquid volume mg/mL when vial quantity is expressed in mg and volume in mL
Required volume = Vial quantity ÷ Target concentration Use this only as a mathematical concentration relationship
Important distinction The table below is a mathematical concentration reference. It does not establish a recommended Melanotan II dose, administration volume, injection schedule, or clinical treatment protocol.
Illustrative Melanotan II concentration examples
| Illustrative vial quantity | 1 mL | 2 mL | 2.5 mL | 3 mL | 5 mL |
|---|---|---|---|---|---|
| 5 mg | 5 mg/mL | 2.5 mg/mL | 2 mg/mL | 1.67 mg/mL | 1 mg/mL |
| 10 mg | 10 mg/mL | 5 mg/mL | 4 mg/mL | 3.33 mg/mL | 2 mg/mL |
The 5 mg and 10 mg rows above are deliberately presented as illustrative mathematical quantities, not as a claim that these are standardized manufacturer vial sizes. Always verify the actual quantity stated on the material being studied.
Need a different vial quantity or BAC-water volume? Use the BacScience universal calculator for custom concentration calculations.
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How Much BAC Water Should Be Added to a Vial of Melanotan II?
The answer depends on the desired research concentration and the quantity of Melanotan II in the vial. For example, a 10 mg quantity mathematically corresponds to 10 mg/mL when divided by 1 mL, 5 mg/mL when divided by 2 mL, and 2 mg/mL when divided by 5 mL.
These calculations describe concentration only. They should not be interpreted as manufacturer instructions or as a recommendation for human use.
How much BAC water for 5 mg of Melanotan II?
Mathematically, a 5 mg quantity produces 5 mg/mL with 1 mL, 2.5 mg/mL with 2 mL, 2 mg/mL with 2.5 mL, approximately 1.67 mg/mL with 3 mL, and 1 mg/mL with 5 mL.
How much BAC water for 10 mg of Melanotan II?
A 10 mg quantity produces 10 mg/mL with 1 mL, 5 mg/mL with 2 mL, 4 mg/mL with 2.5 mL, approximately 3.33 mg/mL with 3 mL, and 2 mg/mL with 5 mL.
How does BAC-water volume change Melanotan II concentration?
Increasing the liquid volume lowers the concentration. Decreasing the liquid volume increases the concentration. The mathematical relationship is inverse: concentration equals the total quantity divided by the liquid volume.
What Is Melanotan II?
Melanotan II (MT-II) is a synthetic cyclic heptapeptide analogue of α-melanocyte-stimulating hormone (α-MSH). PubChem identifies Melanotan II as a synthetic cyclic peptide and lists the molecular formula C50H69N15O9, molecular weight approximately 1024.2 g/mol, and CAS number 121062-08-6.
Its pharmacological research has focused on melanocortin receptor signaling, pigmentation, sexual-function effects, appetite and neuroendocrine pathways. These areas represent different research questions and should not be treated as evidence of an approved therapeutic indication.
How Melanotan II Works
Melanotan II is a melanocortin receptor agonist. Its structure was designed as an analogue of the biologically active region of α-MSH. Research has investigated signaling through melanocortin receptor pathways associated with pigmentation and other physiological processes.
Melanogenesis research
Early human research observed increased pigmentation after exposure to MT-II.
Broader receptor effects
Human studies also investigated effects involving penile erection, sexual desire, nausea, yawning and related physiological responses.
What Is Melanotan II Being Studied For?
Published research has investigated Melanotan II in several areas, including melanogenesis and pigmentation, melanocortin receptor physiology, erectile responses, sexual motivation, appetite-related signaling, and other experimental physiological pathways.
Current clinical research ClinicalTrials.gov lists a recruiting Phase 2 study investigating Melanotan II as an adjunct to narrowband UV-B phototherapy for repigmentation in adults with stable nonsegmental vitiligo. This is an investigational study and does not establish MT-II as an approved treatment.
Human Clinical Research
Human evidence for Melanotan II comes primarily from small, early-stage studies. The best-known early study was a 1996 Phase I investigation involving three healthy male volunteers. Later studies evaluated erectile responses in men with psychogenic or organic erectile dysfunction.
These studies are important for understanding the compound's pharmacological effects, but they do not establish Melanotan II as an FDA-approved treatment.
Regulatory status FDA materials identify Melanotan II as an unapproved drug. FDA has also highlighted potential safety concerns for compounded products containing Melanotan II, including potential immunogenicity associated with aggregation or peptide-related impurities.
Doses Studied in Published Research
Research-dose disclaimer The quantities below are historical doses reported in published research. They are not BacScience dosage recommendations and should not be converted into self-administration instructions.
| Study | Population | Dose reported | Route | Study context | Key finding |
|---|---|---|---|---|---|
| Dorr et al., 1996 | 3 healthy male volunteers | Starting at 0.01 mg/kg; escalation to 0.025–0.03 mg/kg | Subcutaneous | Pilot Phase I investigation | Increased pigmentation was observed in two subjects; nausea and other physiological effects were reported. |
| Wessells et al., 1998 | 10 men with psychogenic erectile dysfunction | 0.025 mg/kg reported | Subcutaneous | Double-blind placebo-controlled crossover study | Erectile responses occurred more frequently with MT-II than placebo; transient adverse effects were reported. |
| Wessells et al., 2000 | 10 men with organic erectile dysfunction | 0.025 mg/kg reported | Subcutaneous | Randomized placebo-controlled crossover study | Erectile responses and increased sexual desire were observed; nausea and yawning were reported. |
Published human research is small relative to the evidence base for approved medicines. The 1996 study involved only three healthy volunteers, while later erectile-function studies enrolled small groups of men. Accordingly, these findings should be interpreted as experimental clinical evidence rather than evidence of an established therapeutic regimen.
Current Clinical Investigation
ClinicalTrials.gov currently lists NCT07437560, a recruiting Phase 2 study investigating Melanotan II as an adjunct to narrowband UV-B phototherapy in adults with stable nonsegmental vitiligo.
The registered study began in February 2026 and is designed to evaluate repigmentation outcomes together with safety monitoring. Because the study is ongoing, its registration should not be interpreted as evidence that efficacy or safety has been established.
Preclinical Research
Melanotan II has been investigated extensively in animal and experimental models. PubChem's literature-linked records include studies involving rodents and melanocortin-related pathways, including research into feeding behavior, body weight, neuroendocrine signaling, thermoregulation, and neural effects.
Human vs. animal evidence Findings observed in mice, rats, cell systems, or other experimental models cannot automatically be translated into human clinical effectiveness, safety, or dosing.
Research Reconstitution & Concentration
For laboratory concentration calculations, the basic relationship is straightforward:
Concentration (mg/mL) = Total Melanotan II quantity (mg) ÷ Liquid volume (mL)
Worked mathematical example: 10 mg quantity
If a hypothetical research vial contains 10 mg of Melanotan II, the resulting mathematical concentration changes with the volume selected:
| Liquid volume | Calculation | Resulting concentration |
|---|---|---|
| 1 mL | 10 mg ÷ 1 mL | 10 mg/mL |
| 2 mL | 10 mg ÷ 2 mL | 5 mg/mL |
| 2.5 mL | 10 mg ÷ 2.5 mL | 4 mg/mL |
| 3 mL | 10 mg ÷ 3 mL | 3.33 mg/mL |
| 5 mL | 10 mg ÷ 5 mL | 2 mg/mL |
These examples demonstrate concentration mathematics only. They do not establish an appropriate preparation volume, route of administration, clinical dose, or human-use protocol.
BAC Water vs. Melanotan II Concentration
The amount of diluent changes concentration but does not change the total quantity of peptide contained in the vial.
Higher concentration
Holding the peptide quantity constant while reducing liquid volume mathematically increases mg/mL.
Lower concentration
Holding the peptide quantity constant while increasing liquid volume mathematically decreases mg/mL.
Not a dose calculation
Concentration and clinical dose are different concepts and must not be treated as interchangeable.
BAC water is a diluent concept used in laboratory and pharmaceutical contexts, but the mathematical concentration relationship itself does not establish whether a particular diluent, volume, container, concentration, or preparation method is appropriate for human use.
Research Limitations & Safety
Melanotan II should not be presented as an FDA-approved tanning, dermatological, sexual-health, or other therapeutic product. FDA records describe Melanotan II as an unapproved drug and have documented regulatory action concerning its marketing as an injectable tanning product.
FDA's current information on certain bulk substances also identifies Melanotan II among substances for which compounded products may pose immunogenicity risks related to aggregation or peptide-related impurities.
Research-use boundary This page provides scientific background and mathematical concentration calculations. It does not provide medical advice, treatment recommendations, or instructions for self-administration of Melanotan II.
Human research has also reported adverse effects including nausea, yawning, fatigue/somnolence and other physiological effects. A published case report additionally described severe systemic toxicity following nonclinical internet-purchased Melanotan II use.
Calculate a custom research concentration Enter your own vial quantity and liquid volume in the universal BacScience BAC Water Calculator.
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Frequently Asked Questions About Melanotan II BAC Water
How much BAC water does Melanotan II require?
There is no single universal volume. The mathematical amount depends on the total Melanotan II quantity and the desired concentration. Different volumes produce different mg/mL concentrations.
How much BAC water for 5 mg of Melanotan II?
As a mathematical example, 5 mg divided by 1 mL equals 5 mg/mL; 5 mg divided by 2 mL equals 2.5 mg/mL; and 5 mg divided by 5 mL equals 1 mg/mL. These are concentration calculations, not preparation or dosing recommendations.
How much BAC water for 10 mg of Melanotan II?
A 10 mg quantity mathematically corresponds to 10 mg/mL with 1 mL, 5 mg/mL with 2 mL, 4 mg/mL with 2.5 mL, 3.33 mg/mL with 3 mL, and 2 mg/mL with 5 mL.
What is the formula for Melanotan II concentration?
Concentration in mg/mL equals total compound quantity in mg divided by liquid volume in mL.
Does adding more BAC water reduce the amount of Melanotan II?
No. In a mathematical concentration model, adding more liquid changes the concentration but does not change the total quantity of compound represented by the vial.
Is Melanotan II FDA approved?
No. FDA materials identify Melanotan II as an unapproved drug. It should not be represented as an FDA-approved tanning or therapeutic product.
Has Melanotan II been studied in humans?
Yes. Small human studies have investigated pigmentation, erectile responses and related physiological effects. A newer ClinicalTrials.gov record also describes an ongoing Phase 2 investigation involving stable nonsegmental vitiligo.
Is there a clinically established human dose for Melanotan II?
No clinically established FDA-approved human dose has been identified. Published studies have reported experimental doses, but those historical research doses are not BacScience recommendations.
What concentration is 10 mg of Melanotan II in 2 mL?
Mathematically, 10 mg ÷ 2 mL = 5 mg/mL.
Can the BacScience BAC Water Calculator calculate Melanotan II concentrations?
Yes. The universal calculator can be used for mathematical concentration calculations by entering the quantity and liquid volume.
Are Melanotan II research doses the same as clinical doses?
No. An experimental dose reported in a study is not automatically an approved clinical dose. Research dose, mathematical concentration, FDA-approved dosage, and community protocol are separate concepts.
What is Melanotan II being investigated for today?
Research has examined melanocortin signaling, pigmentation and other physiological effects. ClinicalTrials.gov currently lists a recruiting Phase 2 study investigating MT-II as an adjunct to NB-UVB phototherapy for stable nonsegmental vitiligo.
Related BacScience Research
Scientific References
-
PubChem — Melanotan II
National Center for Biotechnology Information. Chemical identity, molecular formula, molecular weight, identifiers and linked scientific literature. -
Dorr RT et al. — Evaluation of Melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study.
Life Sciences, 1996. PMID: 8637402. -
Wessells H et al. — Synthetic melanotropic peptide initiates erections in men with psychogenic erectile dysfunction.
Journal of Urology, 1998. PMID: 9679884. -
Wessells H et al. — Effect of an alpha-melanocyte stimulating hormone analog on penile erection and sexual desire in men with organic erectile dysfunction.
Urology, 2000. PMID: 11018622. -
ClinicalTrials.gov — NCT07437560
Melanotan II as an adjunct to NB-UVB phototherapy for repigmentation in stable nonsegmental vitiligo. -
U.S. Food and Drug Administration
FDA regulatory records identifying Melanotan II as an unapproved drug and current information concerning potential risks associated with compounded Melanotan II. -
Melanotan II injection resulting in systemic toxicity and rhabdomyolysis.
Published case report indexed in PubMed, documenting severe toxicity following nonclinical use.
Last Scientifically Reviewed: September 10, 2026
Scientific Review: BacScience Scientific Content Team
Content purpose: Educational and research reference only.
Scientific Review: BacScience Scientific Content Team
Content purpose: Educational and research reference only.