Melanotan II (10 mg)

At a Glance

Melanotan II (MT-II) is a synthetic cyclic heptapeptide analog of α-MSH that drives melanin synthesis via MC1R activation, producing skin pigmentation without UV exposure. MC4R activation simultaneously produces sexual arousal and appetite suppression. This 10 mg vial protocol uses a gradual loading phase to minimise nausea — the most common adverse effect — followed by maintenance dosing 1–2× per week once target pigmentation is reached.[1]

• Reconstitute: Add 3.0 mL bacteriostatic water → 3.33 mg/mL (3,333 mcg/mL).
• Easy measuring: On a U-100 syringe, 1 unit = 0.01 mL ≈ 33.3 mcg. A 1,000 mcg dose = 30 units / 0.30 mL.
• Safety ceiling: Do not exceed 2,000 mcg (2 mg) per day — severe toxicity documented at 6 mg.[3]
• Storage: Lyophilised: freeze at −20 °C; reconstituted: refrigerate at 2–8 °C; use within 1–2 weeks (shorter than most peptides).

Overview

• Goal: Achieve progressive skin pigmentation via MC1R-mediated melanogenesis; suppress appetite and modulate sexual function via MC4R.[1][2]
• Schedule: Daily subcutaneous injection during loading (Weeks 1–8); 1–2×/week maintenance thereafter.
• Dose range: 250 mcg (tolerance) → 1,000 mcg (loading) → 500–1,000 mcg (maintenance).
• Reconstitution: 3.0 mL BAC water per 10 mg vial → 3.33 mg/mL.
• Injection site: Subcutaneous — abdomen, outer thigh, or upper arm; rotate daily.

What You’ll Need

Plan based on an 8-week loading cycle at 1,000 mcg once daily (56 injections, 56 mg total peptide).

• Melanotan II Vials (10 mg each): 56 mg ÷ 10 mg per vial → 6 vials. Note: each reconstituted vial must be used within 1–2 weeks, so reconstitute only 1 vial at a time.
• Insulin Syringes (U-100, 0.5 mL / 50-unit or 1.0 mL / 100-unit): 56 injections → 56 syringes.
• Bacteriostatic Water (10 mL bottles): 3.0 mL per vial → 2 × 10 mL bottles for the full cycle.
• Alcohol Swabs: 2 per injection (vial stopper + injection site) → 112 swabs.

How to Reconstitute

1. Allow the lyophilised vial to reach room temperature (10–15 minutes).
2. Draw 3.0 mL of bacteriostatic water into a sterile syringe.
3. Insert the needle through the vial stopper and inject the water slowly down the inner vial wall to avoid foaming. Do not inject directly onto the powder.
4. Gently swirl — do not shake — until the powder is fully dissolved. The solution should be clear and colourless. Discard if cloudy, discoloured, or particulate.
5. Label with reconstitution date. Refrigerate at 2–8 °C, protected from light. Use within 1–2 weeks. MT-II has a shorter post-reconstitution stability window than many other peptides.

Dosing Schedule

Doses per vial: At 1,000 mcg/day → approximately 10 doses per vial. At 500 mcg maintenance 1×/week → approximately 20 doses per vial.

Tanning onset: Visible pigmentation typically appears after 5–10 daily injections. UV exposure is not required but enhances the depth and duration of the tan.

This guide is for educational purposes only and is not medical advice. For research use only. Not for human consumption.

Protocol Details

• Week 1 starting dose: 250 mcg (≈8 units / 0.075 mL) once daily — assess nausea, flushing, and spontaneous erections.
• Week 2: 500 mcg (15 units / 0.15 mL) once daily.
• Week 3: 750 mcg (≈23 units / 0.225 mL) once daily.
• Weeks 4–8 (loading target): 1,000 mcg (30 units / 0.30 mL) once daily.
• Weeks 9+ (maintenance): 500–1,000 mcg, 1–2× per week.
• Absolute maximum: 2,000 mcg per day — never exceed.[3]

Storage

• Lyophilised: Store at −20 °C (−4 °F); protect from moisture and light.
• Reconstituted: Refrigerate at 2–8 °C. Do not freeze. Use within 1–2 weeks — significantly shorter than most peptides (e.g. BPC-157 is stable for 4 weeks reconstituted). Plan reconstitution accordingly.
• Appearance: Clear, colourless solution. Discard if cloudy, coloured, or particulate.

How Melanotan II Works

MT-II is a cyclic α-MSH analog stabilised by an internal lactam bridge (Ac-Nle4-cyclo[Asp5-His6-D-Phe7-Arg8-Trp9-Lys10]-NH2) that confers greater metabolic stability and receptor potency than the native 13-amino acid α-MSH. It activates four melanocortin receptor subtypes non-selectively:[2]

• MC1R (melanocytes): Drives eumelanin synthesis → skin darkening.
• MC4R (hypothalamus): Central arousal, spontaneous erections, appetite suppression.
• MC3R: Energy homeostasis, anti-inflammatory signalling.
• MC5R: Exocrine gland and immune modulation.

For a detailed explanation of receptor biology and comparison with PT-141, see What Is Melanotan II?

Good to Know

• Safety ceiling — Critical: Do not exceed 2,000 mcg (2 mg) per day under any circumstances. A published case report documented severe rhabdomyolysis (CPK 17,773 IU/L, reference <200 IU/L) following a single 6 mg injection, and a separate case documents renal infarction associated with MT-II use.[3] The 1,000 mcg/day loading target sits well below this threshold.
• Nausea management: Nausea is the most common adverse effect and is worst with the first few injections, particularly as the dose increases. Some researchers take an over-the-counter anti-emetic (e.g. dimenhydrinate or ondansetron, if available) 30 minutes before injecting. Start at the lowest dose (250 mcg) and do not rush the ramp-up.
• Spontaneous erections: MC4R activation produces spontaneous erections regardless of the intended research context. This is expected pharmacology, not a sign of overdose at standard doses. Reducing dose or timing injections for the evening may mitigate this if it is unwanted.
• Short vial life: Reconstituted MT-II should be used within 1–2 weeks. Do not reconstitute multiple vials in advance. Plan your protocol so each vial is used within its stability window.
• Mole monitoring: Darkening of existing naevi (moles) has been documented in MT-II users. Photograph and monitor any moles before and during the protocol; seek dermatological review for any new or changing lesion. MT-II is contraindicated in individuals with a personal or family history of melanoma or with dysplastic naevi.
• Tanning and UV: Visible pigmentation develops over 5–10 daily injections. UV exposure is not required but deepens and prolongs the response. Use sun protection; MT-II pigmentation does not fully protect against UV-induced DNA damage.
• Appetite suppression: MC4R activation reduces appetite. Ensure adequate caloric and protein intake to avoid unintended weight loss during longer protocols.

Injection Tips

• Clean the vial stopper and injection site with separate alcohol swabs; allow both to air-dry fully before proceeding.
• Using a 29–31 gauge insulin syringe (5/16″ to 1/2″ needle), draw the calculated dose precisely.
• Pinch a fold of skin and insert the needle at 45° into subcutaneous fat (90° is acceptable with a short needle into a well-pinched fold).
• Inject slowly over 2–3 seconds; do not aspirate. Withdraw the needle, apply gentle pressure, and do not rub the site.
• Rotate injection sites (abdomen, thighs, upper arms) and dispose of each syringe in a sharps container immediately after use.