Peptide Comparison
Melanotan-2vsPT-141 (Bremelanotide)
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.
The first FDA-approved peptide that works through your brain to reignite sexual desire—think of it as flipping the 'on' switch for arousal rather than just boosting blood flow like traditional ED meds.
At a Glance
Quick
comparison
Dose Range
Melanotan-2
100–500 mcg
PT-141 (Bremelanotide)
1.75–2 mg
Frequency
Melanotan-2
Once daily
PT-141 (Bremelanotide)
As needed
Administration
Melanotan-2
Subcutaneous injection
PT-141 (Bremelanotide)
Subcutaneous injection
Cycle Length
Melanotan-2
4-6 weeks
PT-141 (Bremelanotide)
Ongoing/indefinite
Onset Speed
Melanotan-2
Moderate (1-2 weeks)
PT-141 (Bremelanotide)
Rapid (hours to days)
Evidence Level
Melanotan-2
Limited human trials
PT-141 (Bremelanotide)
Strong human trials (Phase 3 or FDA approved)
Efficacy
Benefit
ratings
Tanning Efficacy
Sexual Function
Tan Longevity
Sexual Desire
On-Demand Use
Clinical Evidence
Technical Data
Compound
specifications
Melanotan-2
Molecular Formula
C50H69N15O9
Molecular Weight
1024.18 g/mol
Half-Life
33-36 hours
Bioavailability
High (subcutaneous injection)
CAS Number
121062-08-6
PT-141 (Bremelanotide)
Molecular Formula
C50H68N14O10
Molecular Weight
1025.2 g/mol
Half-Life
2.7 hours
Bioavailability
~100% (subcutaneous injection)
CAS Number
189691-06-3
Protocols
Dosing
tiers
Melanotan-2
PT-141 (Bremelanotide)
Applications
Best
suited for
Melanotan-2
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.
PT-141 (Bremelanotide)
Women with Low Sexual Desire (HSDD)
PT-141 is FDA-approved specifically for premenopausal women with acquired, generalized hypoactive sexual desire disorder—when you used to have normal desire but it's faded, and it's causing real distress in your life. It's the only approved treatment that works through brain pathways rather than hormones.
Men Who Don't Respond to Viagra-Type Medications
While not FDA-approved for men, clinical research shows PT-141 may help men with erectile dysfunction who don't respond to PDE5 inhibitors like Viagra or Cialis. Because it works through the brain rather than blood vessels, it offers a completely different approach.
Those Wanting On-Demand Treatment
Unlike daily medications like flibanserin (Addyi), PT-141 is used only when you want it—take it 45 minutes before intimacy. This gives you control over timing without committing to daily pills.
People Seeking to Address the 'Wanting' Part of Intimacy
Many sexual health treatments focus on the physical mechanics (blood flow, lubrication). PT-141 is unique because it targets desire itself—the psychological 'wanting' that initiates intimacy. It works on your brain's arousal circuits.
Safety Profile
Side
effects
Melanotan-2
Common
- Facial flushing
- Nausea
- Darkening of moles and freckles
- Spontaneous erections (men)
- Drowsiness and fatigue
Uncommon
- New mole formation
- Headaches
Serious
- Priapism (prolonged erection)
- Concerning mole changes
PT-141 (Bremelanotide)
Common
- Nausea
- Facial flushing
- Headache
- Injection site reactions
Uncommon
- Skin darkening (hyperpigmentation)
Serious
- Blood pressure increase
Research Status
Safety
& evidence
Melanotan-2
Evidence Level
Limited human trials
FDA Status
Not FDA approved
Safety Overview
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.
Contraindications
- xHistory of melanoma or skin cancer
- xFamily history of melanoma
- xLarge number of atypical moles
- xPregnancy or breastfeeding
- xSevere cardiovascular disease
PT-141 (Bremelanotide)
Evidence Level
Strong human trials (Phase 3 or FDA approved)
FDA Status
FDA approved for this use
Safety Overview
PT-141 has undergone rigorous FDA review and was approved in 2019 based on two large Phase 3 clinical trials involving over 1,200 women. The most common side effect is nausea (affecting about 40% of users), which typically decreases with repeated use. The drug causes transient increases in blood pressure (average 2-3 mmHg) and slight decreases in heart rate, which is why it's contraindicated in uncontrolled hypertension. Long-term safety data from the 52-week extension study showed no new safety concerns.
Contraindications
- xUncontrolled high blood pressure
- xCardiovascular disease
- xHistory of heart attack or stroke
- xPregnancy or planning pregnancy
- xCurrently breastfeeding
Decision Guide
Which is
right for you?
Choose Melanotan-2 if...
- Achieving a natural-looking tan
- Reducing sun exposure time
- Enhancing libido and sexual function
- Appetite suppression
Choose PT-141 (Bremelanotide) if...
- Restoring sexual desire
- Treating hypoactive sexual desire disorder (HSDD)
- Enhancing arousal response
- Supporting intimacy when desire is low