Melanotan 2 (MT-2) Peptide Guide: Dosing, Reconstitution & Safety (2026)

An educational research guide to Melanotan 2 (MT-2): how it works, common loading and maintenance schedules used in research planning, reconstitution math, side effects, and how it compares to PT-141 and afamelanotide.

Melanotan 2 Quick Start

Melanotan 2 (also written MT-2, MT-II, or melanotan ii) is a lab-made peptide. It was first developed at the University of Arizona in the 1980s and 1990s. The goal was to find a way to trigger tanning without long sun exposure.

MT-2 copies a natural hormone in the body called alpha-MSH. Alpha-MSH helps control skin color. The lab version is stronger and lasts longer than the natural one, which is why it has bigger effects but also more side effects.

Most research workflows use a daily loading phase followed by a weekly maintenance dose. The most common vial size is 10 mg, and the most common route is subcutaneous (SubQ) injection. Some studies also tested intranasal use.

Use this page for dose steps, timing, vial mixing, and storage. 

Route
Subcutaneous (SubQ) injection is the most studied route. Intranasal spray has been tested but is less predictable.

Measure
Use a U-100 insulin syringe. The unit math depends on how much BAC water you mix with the 10 mg vial.

Loading
A common research framework starts at 100-250 mcg daily and escalates to 500-1000 mcg as nausea tolerance improves.

Maintenance
After loading, many users drop to 1-2 doses per week to hold pigmentation.

Research status
Not FDA-approved. Illegal to sell for human use in the US, UK, and Australia.

Disclaimer
This page is an educational research reference. It is not medical advice and not a treatment plan. Melanotan 2 is not FDA-approved and is sold for research use only.

Melanotan 2 Dosing Protocol & Schedule
There is no FDA-approved dose for Melanotan 2. The schedules below are common research-planning frameworks built from early human studies and community use. They are not personal medical advice.

Most workflows use two phases. Loading is daily dosing to build pigment. Maintenance is one or two doses per week to hold it. Nausea is the main reason people slow down or pause dose increases.

Melanotan 2 Dosing Framework
Pick the phase you are researching to see the typical dose and timing notes.

Loading Phase

ED Trial Dosing (Context Only)
Daily dosing used to build pigmentation during the first 4-6 weeks.

Loading Phase - Daily Dosing

Stage                  Days                Dose               Notes
Assessment     Days 1-3    100-250 mcg daily    Used to check                                                                          how well nausea                                                                          and flushing                                                                                 are tolerated.

Low loading    Days 4-14   250-500 mcg daily   Step up only if                                                                            side effects stay                                                                         manageable.  Standard

loading         Weeks 3-5    500-1000 mcg daily     Continued                                                                                 until  target                                                                         pigment is reached.                                                                              Brief                                                                           UV exposure is often                                                                          coordinated.

Bedtime dosing is commonly used so peak nausea happens during sleep.

Skin type matters
Lighter skin types (Fitzpatrick I-II) usually see changes sooner and at lower doses. Darker skin types may need a longer loading window before visible changes appear.

Cycle Guidelines
Common Cycle Lengths

Approach                     Duration                             Off Period                                      Best For
Short cycle                   4 weeks                               4+ weeks                                  First-time research planning
Standard cycle            6 weeks                               4-6 weeks                                 Building visible pigment
Extended cycle            8 weeks                               6+ weeks                                Slower titration or stronger nausea profile
Long-term controlled safety data is limited. Many frameworks cap loading at 8 weeks.

Evidence boundary
No FDA-approved dose exists. Loading and maintenance models are community-derived and informed by small early-phase studies. Personal medical decisions should involve a licensed clinician.

Melanotan 2 Reconstitution Guide

Melanotan 2 ships as a dry white powder in a 10 mg vial. You mix it with bacteriostatic (BAC) water to turn it into a liquid you can draw into a syringe. The amount of water you add changes the concentration and the unit math.

Find the BAC water volume you plan to use in the table below, then read across to see the syringe units for your target dose. All units assume a U-100 (1 mL = 100 units) insulin syringe.

Melanotan 2 Dosage Chart

This Melanotan 2 dosage chart summarizes the common loading and maintenance framework, with dose escalation shown by phase and schedule.

How Melanotan 2 Works
Melanotan 2 works by turning on a family of receptors in your body called melanocortin receptors. These receptors sit on different cells and control different things: skin pigment, hunger, sexual signaling, and more.

Most modern drugs are designed to hit only one receptor. MT-2 hits several at once. That is why it produces several effects at the same time - and also more side effects than newer, targeted versions.

MC1R - tanning
MC1R sits on the pigment-making cells in your skin. When MT-2 turns it on, those cells make more melanin, which is the natural brown pigment that darkens skin.

MC3R and MC4R - sexual signaling
MC3R and MC4R sit in the brain and control sexual arousal. This is a brain-level effect, not a blood-flow effect like Viagra.

MC4R - appetite
The same brain receptors involved in arousal also help control hunger. Many users report less appetite while loading.

MC5R - secondary effects
MC5R sits mostly in glands. It is less linked to obvious effects but may add to the overall side-effect picture.

Because MT-2 turns on all of these receptors at once, researchers later built more focused versions. Afamelanotide mostly hits MC1R and is FDA-approved for a rare skin condition called erythropoietic protoporphyria. Bremelanotide (PT-141) mostly hits MC3R/MC4R and is FDA-approved for low sexual desire in women.

Who Melanotan 2 Is For and Who Should Avoid It
MT-2 is a research compound. It is not approved for any medical use. People typically researching it are interested in tanning response, melanocortin signaling, or appetite/sexual function research. Personal use carries real risk and should involve a clinician.

The groups below have higher risk and are usually flagged in case reports and clinical commentary.

Personal or family history of melanoma
Case reports have linked MT-2 use to mole changes and melanoma diagnoses. People with prior skin cancer or strong family history should avoid it.

Many moles or atypical moles
MT-2 darkens existing moles and can trigger new ones. Anyone with lots of moles or atypical (dysplastic) moles is at higher risk of missing a real warning sign.

Cardiovascular conditions
Flushing, blood pressure changes, and rare reports of more serious events suggest people with uncontrolled cardiovascular disease should avoid use.

History of priapism or sickle cell trait
Case reports include priapism, which is a prolonged, painful erection that needs medical care. Anyone with a higher baseline risk should avoid MT-2.

Pregnancy and breastfeeding
No human safety data exists for these groups. MT-2 should not be used during pregnancy or while breastfeeding.

Active medications that affect blood pressure or arousal
There is little drug-interaction data. People on blood pressure, ED, or psychiatric medications should review options with a clinician first.

Melanotan 2 Side Effects & Safety
Most MT-2 side effects show up early in loading and at higher doses. Many fade as the body adjusts, but a few are more serious and need attention.

Common: nausea and flushing
Nausea is the most common reason people slow down or stop. Flushing (a warm, red feeling in the face and chest) is also frequent. Both tend to ease over the first 1-2 weeks of dosing.

Common: appetite changes, fatigue, yawning
Many users report eating less, feeling sleepy, or yawning soon after a dose. These are linked to the same melanocortin pathways that affect the brain.

Sexual: spontaneous erections and increased desire
Trial data show MT-2 can cause unplanned erections and higher sexual desire. This is a brain-signaling effect, not a blood-flow drug like Viagra.

Dermatologic: darkening moles and new moles
MT-2 can darken existing moles, freckles, and other spots. Case reports describe new moles appearing and rapid changes in old ones after only one or two doses. Because mole changes can sometimes signal melanoma (a serious skin cancer), close monitoring is important.

Serious: priapism
A few case reports describe priapism, which is a painful, lasting erection. It is a medical emergency and needs urgent care.

Serious: rhabdomyolysis at overdose levels
Overdose case reports describe rhabdomyolysis, which is when muscle tissue breaks down and can harm the kidneys. These cases involved doses far above typical research-planning ranges.

Watch your moles closely
Baseline and periodic photographs of moles are a commonly recommended safety practice. Any mole that changes shape, color, or size, or begins to bleed, warrants stopping and seeing a dermatologist.

Melanotan 2 Timeline & What to Monitor
Tanning is not instant. The body needs time to make new melanin and move it into the skin. Sexual and appetite effects can show up faster but vary widely from person to person.

What to Expect by Week

Window Likely Pattern What to Track
Days 1-3 Most nausea and flushing happen here. Skin usually looks the same. Tolerance level, whether bedtime dosing helps with nausea.

Weeks 1-2 Some users notice freckling or slight darkening, especially with light UV exposure. Mole photos, first signs of pigment change, side-effect intensity.

Weeks 3-4 Pigment changes are more visible. Sexual and appetite effects often plateau. Compare baseline mole photos. Note if any mole looks different.

Weeks 5-8 Loading often wraps up here. Many users move to weekly maintenance. Decide if the result is enough or if more loading is needed.

After loading Pigment fades slowly without maintenance dosing or regular UV exposure. How long pigment lasts at your chosen maintenance dose.

Mole photos
Take wide and close-up phone photos of every visible mole before you start. Re-photograph every 2-4 weeks. Compare them side by side.

Skin exam
A baseline full-skin exam with a dermatologist before starting is the most useful single safety step, especially for anyone with many moles or fair skin.

Blood pressure
Anyone with a blood-pressure history should have it monitored by a clinician before and during any use.

Side-effect log
General symptom tracking commonly includes nausea level, flushing, sleep changes, and any new symptoms.

Melanotan 2 Clinical Evidence Context
The published human evidence for MT-2 is small and old. Most trials were done in the 1990s and early 2000s with 20 to 100 participants. They showed real tanning and sexual-function effects but also high nausea rates at clinical doses. No large modern trials have been done.

Dorr et al. 1996 - Phase I, healthy volunteers
Showed clear pigmentation gains with frequent nausea and spontaneous erections at studied doses.

Wessells et al. 1998 - Phase II, psychogenic ED
Placebo-controlled study reporting strong erection-response signals in most treated participants.

Wessells et al. 2000 (Urology) - Phase II, organic ED
Reported better erection response and rigidity time vs. placebo in men with organic ED.

Wessells et al. 2000 (combined) - mixed ED
Combined analysis showing higher sexual desire and robust erection frequency, with notable nausea rates.

Dorr et al. 2004 - Phase I, MT-2 plus UV
MT-2 combined with brief UV exposure produced stronger tanning than UV alone in healthy volunteers.

Minakova et al. 2019 - preclinical mouse model
Animal study suggesting MT-2 may affect social behavior through MC4R-oxytocin signaling. Not human evidence.

Bottom line: small early studies confirmed MT-2 produces measurable tanning and sexual-function effects, but at the cost of nausea and a broad side-effect profile. Rather than continue MT-2 development, researchers built more selective successors: afamelanotide for tanning (FDA-approved for a rare skin condition) and bremelanotide / PT-141 for sexual function (FDA-approved for low sexual desire in women). MT-2 itself was never submitted for FDA approval.

Melanotan 2 Protocol Mistakes & Troubleshooting

Nausea is too strong

Persistent or difficult-to-manage nausea warrants clinician review; dose and timing changes should be made with a clinician rather than self-directed.

Mole looks different

A changing mole warrants stopping, documenting the change, and seeing a dermatologist.

Missed dose

Reported protocols typically skip a missed dose and return to the regular schedule because pigment builds slowly and one missed dose has little impact.

Cloudy or off-color vial

Do not use it. Cloudiness suggests bacterial contamination or breakdown. Reconstitute a new vial.

No visible tanning after 3-4 weeks

Check three things: vial concentration, syringe math, and UV exposure. Many users do not see pigment without brief, controlled sunlight or tanning-bed exposure.

Unexpected erection or strong arousal

This is a known central effect reported in trials; timing and dose changes should involve a clinician.

Storage mistake

If a reconstituted vial was left at room temperature for more than a few hours, do not use it. Refrigerate fresh batches as soon as they are mixed.