Peptide Profile
Melanotan-2
A powerful synthetic peptide that mimics your body's natural tanning hormone, giving you a deeper, longer-lasting tan with minimal sun exposure while also showing surprising benefits for libido and appetite.
Dose Range
100-500mcg
Frequency
Once daily
Route
Subcutaneous injection
Cycle Length
4-6 weeks
Onset
Moderate (1-2 weeks)
Evidence
Limited
Compound Profile
Scientific & Efficacy Data
C50H69N15O9
Molecular Formula
1024.18 g/mol
Molecular Weight
Developed By · 1991
Victor J. Hruby and Mac E. Hadley
University of Arizona
Primary Benefits
Highly effective at inducing skin darkening with minimal UV exposure—works on even the fairest skin types
Significant effects on libido and arousal in both sexes—a notable secondary benefit (or side effect)
Creates long-lasting color that persists for weeks between doses and can be maintained year-round
Amino Acid Sequence
Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2Dosing
How much
do I take?
Starting Dose
100-250 mcg
Start low to assess your tolerance. Nausea and flushing are common at first but usually decrease. Taking it before bed helps you sleep through any nausea. This loading phase builds up melanin in your system.
Standard Dose
250-500 mcg
This is the typical loading phase. Use daily until you reach your desired tan (usually 2-3 weeks), then switch to maintenance dosing. Brief sun or UV exposure (10-20 minutes) speeds up results.
Advanced Dose
500 mcg
Once you've achieved your desired tan, maintenance doses keep it topped up. Some users only need 500mcg once or twice weekly to maintain color year-round. The long half-life means you don't need daily dosing.
Timing
Best time to take
Evening or before bed works best for most people. This helps you sleep through any initial nausea or flushing. The long half-life (33+ hours) means timing isn't critical for effectiveness.
With food?
Taking MT-2 on an empty stomach speeds absorption but may increase nausea. If nausea is an issue, try a light snack 30-60 minutes before. Once you're past the first week, food timing matters less.
If stacking
If using with other peptides, inject at different sites. MT-2 is often the only peptide people use at bedtime due to the drowsiness it can cause. Don't combine with PT-141 on the same day—both affect the same receptors.
Adjusting Your Dose
Increase if
- +You've used starting doses for a week with minimal side effects
- +You're not seeing color development after 2 weeks with some UV exposure
- +Your maintenance dose isn't holding your tan between doses
Decrease if
- -Nausea persists beyond the first week
- -Flushing is severe or uncomfortable
- -You're experiencing unwanted sexual side effects
- -New moles are appearing (consult dermatologist)
Signs of right dose
- ✓Gradual, natural-looking tan development
- ✓Minimal nausea after the first few doses
- ✓Stable color that lasts between maintenance doses
- ✓No concerning changes to existing moles
Dosing Calculator
Calculate Your Exact Dose
Amount to Draw
10
units
Suitability
Is this
right for me?
Best For
Fair-Skinned Individuals Who Struggle to Tan
If you're the type who burns before you bronze, MT-2 can be a game-changer. It works by telling your skin cells to produce more melanin—the pigment that creates a tan. People who normally can't tan often see the most dramatic results.
Those Wanting to Reduce Sun Exposure
MT-2 means you need far less UV exposure to develop and maintain a tan. A few minutes of sun or a brief tanning bed session goes much further. This could potentially reduce your cumulative UV damage over time.
Year-Round Tan Maintenance
Unlike a natural tan that fades quickly, MT-2 tans last longer and can be maintained year-round with minimal upkeep. Many users find they can keep their summer color through winter with just weekly maintenance doses.
Those Experiencing Low Libido
MT-2 has significant effects on sexual arousal and function in both men and women. While PT-141 is more targeted for this purpose, some users appreciate getting tanning and libido benefits from one peptide.
Consider Alternatives If
Who Should Avoid
Do not use if
- ×You have a personal or family history of melanoma—MT-2 stimulates melanocytes, and the effects on pre-existing abnormal cells are unknown
- ×You have numerous atypical (dysplastic) moles—these need monitoring, not stimulation
- ×You are pregnant or breastfeeding—effects on fetal development are unknown
- ×You have severe heart conditions—MT-2 can temporarily raise blood pressure
- ×You've had allergic reactions to peptides in the past
- ×You have Addison's disease or other adrenal disorders
Use with caution if
- !You take blood pressure medications—MT-2 can affect cardiovascular function
- !You use erectile dysfunction drugs—combining with MT-2 may cause dangerous prolonged erections
- !You have many moles—get a baseline skin check first and monitor regularly
- !You have a history of priapism—MT-2 can trigger prolonged erections
- !You're taking immunosuppressant medications—effects on immune function are unclear
- !You have autoimmune skin conditions—response to increased pigmentation is unpredictable
Administration
How do I
use it?
Reconstitution
What you need
- •Bacteriostatic water (BAC water)—the preservative allows multiple uses
- •Insulin syringes (29-31 gauge) for precise dosing
- •Alcohol swabs for sterilization
- •Your Melanotan-2 powder vial (typically 10mg)
Injection
Route
Subcutaneous injection (just under the skin)—this is the most common and effective method for MT-2
Best sites
- •Belly fat area (1-2 inches from belly button)—most popular site
- •Front or outer thigh (middle section)
- •Back of the upper arm (if you can reach)
Technique
- 1.Wash your hands thoroughly with soap and water
- 2.Clean the injection site with an alcohol swab and let it dry
- 3.Pinch about an inch of skin to create a fold
- 4.Insert the needle at a 45-90 degree angle
- 5.Inject slowly and steadily—rushing can increase nausea
- 6.Wait 5-10 seconds before removing the needle
- 7.Don't rub the site—just light pressure if needed
Storage
Signs of degradation
Sample Daily Schedule
Safety
Is it
safe?
Safety Profile
Melanotan-2 has been studied in clinical trials and shows a generally acceptable short-term safety profile when used as directed. The most common side effects—nausea and flushing—are usually temporary and decrease with continued use. However, MT-2 is not FDA approved, and long-term safety data is limited. The main safety concern is the unknown effect on melanocytes (pigment-producing cells), particularly in people with a history of melanoma or atypical moles.
MT-2 was developed at the University of Arizona and has undergone multiple clinical trials for tanning and sexual dysfunction. While short-term studies show reasonable safety, long-term effects on skin cancer risk are not definitively known. Anyone using MT-2 should get regular skin checks from a dermatologist.
Common Side Effects
Experienced by some users
Facial flushing
Your face may turn red and feel warm shortly after injection. This is one of the most common effects, especially in the first week. It's caused by MT-2's effects on blood vessels.
Management: Usually subsides within 30-60 minutes. Taking MT-2 before bed helps. Flushing typically decreases significantly after the first week as your body adjusts.
Nausea
Many users feel queasy after injection, especially at higher doses or during the first week. This is the most common reason people struggle with MT-2.
Management: Start with lower doses (100-150 mcg) and work up. Take before bed to sleep through it. A light snack beforehand may help. Anti-nausea medications can be used if needed.
Darkening of moles and freckles
Existing moles, freckles, and any pigmented areas will darken along with your skin. This is expected but needs monitoring.
Management: Get a baseline skin check before starting. Monitor moles for any changes in size, shape, or color. See a dermatologist if any mole looks concerning.
Spontaneous erections (men)
MT-2 activates the same pathways as PT-141, so increased erections are common, especially during the loading phase.
Management: Usually decreases as your body adjusts. If problematic, reduce dose. Never combine with ED medications like Viagra—risk of priapism.
Drowsiness and fatigue
Many people feel tired or drowsy after injection, likely related to MT-2's effects on the nervous system.
Management: This is why evening dosing is recommended. Use it to your advantage—inject before bed and let it work while you sleep.
Less Common
- •New mole formation
- •Headaches
These typically resolve with continued use or dose adjustment.
Stop and Seek Help If
- ×Any mole shows concerning changes (growth, irregular borders, color changes, bleeding)
- ×You develop new moles that appear atypical or concerning
- ×Nausea or flushing remains severe beyond the first week
- ×You experience priapism or prolonged erection
- ×Any signs of allergic reaction (difficulty breathing, significant swelling)
- ×You've achieved your desired tan and completed your cycle
Melanotan-2 is not FDA approved and is considered a research compound. The long-term effects on skin cancer risk are not definitively known. Regular dermatological monitoring is essential for anyone using MT-2. This information is educational only—consult a healthcare provider before use.
Interactions
With other peptides
- !Both act on melanocortin receptors. Don't use on the same day—effects may compound unpredictably. PT-141 is more targeted for sexual function.
- ✓No known interaction. Can be used together safely for general wellness benefits. Inject at different sites.
- ✓Safe combination. GHK-Cu supports skin health through different mechanisms, complementing MT-2's tanning effects.
- ✓Generally safe to combine. Separate injection times by at least 30 minutes.
With medications
- !Erectile dysfunction drugs (Viagra, Cialis, Levitra) - NEVER combine—serious risk of priapism (dangerous prolonged erection). Wait at least 24-48 hours between MT-2 and ED medications.
- !Blood pressure medications - MT-2 can temporarily affect blood pressure. Monitor BP closely and inform your doctor about MT-2 use.
- !Antidepressants (SSRIs) - Potential for interaction affecting sexual side effects. Use with caution and monitor your response.
- ✓Antihistamines - Some antihistamines may help with nausea and flushing. Generally safe to combine.
With supplements
- ✓Vitamin D - Safe and potentially beneficial. Vitamin D supports skin health and you'll need less sun exposure with MT-2.
- ✓Antioxidants (Vitamin C, E) - Safe to combine. May offer additional skin protection.
- ✓Tyrosine - Tyrosine is a melanin precursor. Some believe it enhances MT-2 results, though this isn't proven. Safe to take together.
- ✓Ginger or anti-nausea supplements - Can help manage MT-2-induced nausea during the loading phase.
Effectiveness
Does it
work?
Evidence Level
Limited human trials
What to Expect
Days 1-5
What you might notice
- •Facial flushing shortly after injection (very common)
- •Nausea that may last 30-60 minutes (common)
- •Feeling tired or drowsy (take at bedtime!)
- •Increased libido or spontaneous erections (men)
- •Little to no visible tan yet—melanin is building up
What's normal
- •Flushing and nausea are common and usually decrease by day 5-7
- •Some people feel nothing at all initially
- •Existing freckles and moles may start darkening first
What's next
- →Continue daily dosing during loading phase
- →Get brief UV exposure (10-15 min) every few days to activate melanin
- →Side effects typically improve significantly after the first week
Weeks 1-2
What you might notice
- •Visible tan starting to develop, especially on sun-exposed areas
- •Moles and freckles noticeably darker
- •Side effects decreasing significantly
- •Enhanced libido effects becoming apparent
- •Possible slight appetite suppression
What's normal
- •Tan develops gradually, not overnight
- •Different body areas may tan at different rates
- •Face and arms often show color first
What's next
- →Continue daily dosing until you reach desired color
- →Regular brief UV exposure speeds results
- →Monitor moles for any concerning changes
Weeks 3-4 and beyond
What you might notice
- •Your tan reaching its peak depth
- •Very minimal side effects at this point
- •Color appearing on areas that rarely get sun
- •Long-lasting tan that fades very slowly
What's normal
- •You may have reached your genetic tanning potential
- •Side effects should be minimal or gone
- •Tan persists well between doses
What's next
- →Switch to maintenance dosing (2-3 times per week)
- →Occasional UV exposure maintains color
- →Many users maintain year-round tan with just weekly doses
Signs It's Working
Tanning Response
- ✓Gradual darkening of skin, especially sun-exposed areas
- ✓Freckles and moles becoming darker
- ✓Tan developing faster than normal with UV exposure
- ✓Tan lasting longer and fading more slowly
- ✓Even areas that rarely get sun developing some color
Sexual Health Effects
- ✓Increased libido or sexual interest
- ✓Improved erectile response (men)
- ✓Enhanced arousal (women)
- ✓Spontaneous erections (men)—indicates the peptide is active
Other Effects
- ✓Reduced appetite (common side effect that some find beneficial)
- ✓Decreased side effects over time (shows adaptation)
- ✓Consistent results with maintenance dosing
Not Seeing Results?
Common reasons
- •Not getting any UV exposure—MT-2 produces melanin but you need some UV to 'activate' it and see the tan
- •Degraded peptide from improper storage—check if solution is clear and properly refrigerated
- •Dose too low—some people need the full 500mcg to see results
- •Unrealistic expectations—MT-2 won't make you darker than your genetic potential allows
- •Not enough time—full results take 2-4 weeks of consistent loading
- •Poor quality peptide from unreliable source—always verify with third-party testing (COA)
Key Research
"Subcutaneous administration of melanotan II, a melanocortin-1 receptor agonist, induces tanning in healthy subjects"
Dorr RT, Dvorakova K, Brooks C, et al., 2000
Finding: This clinical trial confirmed that MT-2 successfully induced skin darkening in healthy volunteers. Importantly, the tan developed even in areas not exposed to UV light, proving MT-2 works by actually increasing melanin production rather than just enhancing UV response.
View Study"A synthetic analog of alpha-melanocyte stimulating hormone that is a superpotent activator of melanogenesis"
Sawyer TK, Sanfilippo PJ, Hruby VJ, et al., 1980
Finding: The foundational research that led to MT-2 development showed that synthetic MSH analogs could be far more potent than natural hormones at stimulating melanin production. This work at the University of Arizona laid the groundwork for all tanning peptides.
View Study"Melanotan II - a new approach to clinical investigations of the melanocortin peptide family"
Hadley ME, Dorr RT, 2006
Finding: This comprehensive review documented MT-2's effects on tanning, sexual function, and appetite across multiple studies. The authors noted its potential for treating various conditions while also highlighting the need for more long-term safety research.
View Study"Safety and efficacy of subcutaneous Melanotan-II for tanning purposes"
Ugwu SO, Blanchard J, Dorr RT, et al., 1997
Finding: Clinical testing showed MT-2 was well-tolerated at doses up to 0.03 mg/kg with predictable side effects (flushing, nausea). The study established effective dosing ranges that are still used today and confirmed the peptide's efficacy for skin pigmentation.
View Study"Initiation of human melanocyte culture through melanocortin-1 receptor with the use of an alpha-MSH analogue"
Abdel-Malek Z, Scott MC, Suzuki I, et al., 1999
Finding: This research helped explain how MT-2 works at the cellular level, showing that melanocortin receptor activation leads to increased melanin synthesis in human melanocytes. This confirmed the peptide's mechanism of action in human skin cells.
View StudyFrequently Asked Questions