PT-141
FDA APPROVED
Fda Approved
Sexual
PT-141
7
Amino acids
Molecular weight
Peptide
Type
PT-141 (bremelanotide) is a synthetic cyclic heptapeptide and melanocortin receptor agonist approved by the FDA in 2019 under the brand name Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women. It acts centrally via MC3R and MC4R activation in the hypothalamus to increase sexual desire and arousal — a mechanism distinct from vascular-targeting agents like sildenafil. It is also used off-label in men for low libido and erectile dysfunction.
Top researched benefits
Overview of PT-141
PT-141 selectively activates melanocortin-3 and melanocortin-4 receptors (MC3R/MC4R) in the hypothalamus, paraventricular nucleus, and limbic regions, triggering dopaminergic and neurogenic signaling cascades that elevate sexual motivation and arousal. Unlike PDE5 inhibitors, it crosses the blood-brain barrier and enhances desire through central nervous system pathways rather than peripheral vascular mechanisms.
sexual health
- FDA-approved for treatment of HSDD in premenopausal women.
- Effective in men including PDE5 inhibitor-resistant cases via CNS pathways.
- Enhances sexual arousal and desire in women.
quality of life
- Reduces distress related to low sexual desire.
- Enhanced satisfaction reported in clinical trials.
Typical Dose
1.75mg per injection
Frequency
as needed, no more than once per 24 hours (max 8 doses per month)
Cycle Duration
on-demand use; reassess after 3 months
Storage
Lyophilized: store at -20°C or below, desiccated. Reconstituted: refrigerate at 2–8°C and use within 28 days; for longer storage freeze below -18°C.
Chemical Makeup
Key benefits
In the RECONNECT Phase 3 trials (Studies 301 and 302), bremelanotide produced statistically significant improvements in FSFI desire domain scores versus placebo (0.30–0.42 increase, p<0.001) in premenopausal women with HSDD
Significantly reduces desire-related distress as measured by FSDS-DAO item 13, with reductions of 0.29–0.37 versus placebo (p<0.001) in the RECONNECT trials
Enhances sexual desire and arousal in both men and women through central MC3R/MC4R activation, addressing low libido at the neurological level rather than through vascular or hormonal mechanisms
Improves erectile function in men via a central mechanism independent of vascular pathways, benefiting patients who do not respond adequately to PDE5 inhibitors
Community interest
This peptide is still gaining traction in the community.
Melanocortin Agonist | Sexual Dysfunction Treatment
This overview is informational and based on aggregated descriptions from studies and user reports.
Was it helpful?YesNoPT-141 Molecular Information
View the scientifc details of PT-141.
7
Amino Acids
PT-141
?
?
Position 1
Asp
Asp
Position 2
His
His
Position 3
Phe
Phe
Position 4
Arg
Arg
Position 5
Trp
Trp
Position 6
Lys
Lys
Position 7
Molecular Weight
1025.18DaChain Length
7Amino AcidsType
PeptidePT-141 Protocols
Subcutaneous injection is the FDA-approved delivery route for PT-141 (bremelanotide), administered into the abdomen or thigh 45–60 minutes before sexual activity. This route provides near-complete bioavailability and is the standard for both female HSDD at 1.75 mg (Vyleesi) and off-label male erectile dysfunction use; dosing is strictly event-based, not scheduled, with a maximum of one dose per 24 hours and no more than 8 doses per month.
| Goal | Dosage | Frequency | Route |
|---|---|---|---|
| Restore sexual desire and arousal in premenopausal women with acquired HSDD at the FDA-approved therapeutic dose | 1.75 | 1 day range | SubQ (abdomen or thigh) |
| Improve erectile function in men with organic or psychogenic erectile dysfunction at the primary off-label therapeutic dose | 1.75 | 1 day range | SubQ (abdomen or thigh) |
| Establish tolerability at a sub-therapeutic dose on first use before progressing to the standard 1.75 mg event dose | 0.5 | 1 day range | SubQ (abdomen or thigh) |
| Achieve partial erectile or arousal response at an intermediate dose during a structured titration phase before reaching full therapeutic dose | 1 | 1 day range | SubQ (abdomen or thigh) |
| Restore erectile response in men who have failed PDE5-inhibitor monotherapy by combining central melanocortin activation with peripheral vasodilation | 1 | 1 day range | SubQ (abdomen or thigh) |
| Maximize central arousal response in high-tolerance users who have not achieved sufficient effect at 1.75 mg | 2 | 1 day range | SubQ (abdomen or thigh) |
Reconstitution Instructions
Materials needed:
Steps to reconstitute
- Wipe the rubber stopper of the PT-141 vial and the BAC water vial with separate alcohol swabs and allow both to air dry
- Draw the desired volume of bacteriostatic water into an insulin syringe — for a 10 mg vial, draw 2 mL BAC water to yield a 5 mg/mL concentration
- Insert the needle through the rubber stopper of the PT-141 vial and inject the BAC water slowly down the inner glass wall — never directly onto the powder
- Gently swirl or roll the vial between your palms until the powder is fully dissolved — do not shake
- Label the vial with the date, concentration, and your name; refrigerate at 2–8°C and use within 28–30 days
- When ready to dose, draw the appropriate volume into a fresh insulin syringe (e.g. 0.35 mL for 1.75 mg from a 5 mg/mL solution)
- Clean the injection site (abdomen 2 inches from the navel, or outer thigh) with an alcohol swab and allow to dry
- Pinch a fold of skin and insert the needle at a 45–90 degree angle; slowly depress the plunger and withdraw
- Apply gentle pressure with a clean swab — do not rub the site
PT-141 Cycle
The PT-141 Cycle section explains how long a typical cycle lasts and what to expect during each phase. Over time, your body can become less responsive with continuous use.
Taking breaks between cycles may help maintain effectiveness and support better overall results.
- Week 0-0
- Mild nausea or facial flushing possible
- Week 0-0
- Onset of effects - increased arousal and desire
- Week 0-0
- Peak effects - enhanced sexual response
- Week 0-0
- Gradual diminishment of effects
Dosing tools
PT-141 Peptide Dosage Calculator
Calculate peptide doses with our visual syringe guide.
mg
Enter the total amount of peptide in the vial in milligrams (as stated on the label).
The dose you want to inject per administration, in mcg or mg.
1,000 mcg = 1 mg
1 mL
2 mL
3 mL
5 mL
Custom
Volume of bacteriostatic water you add to reconstitute the powder. Use BAC water for preservation.
Injection Results
Based on your vial and dilution inputs.
PT-141
SINGLE COMPOUNDVolume per injection
0.05
mL
Concentration
10.00
mg/mL
Doses per vial
20
doses
Total injections per vial
20 injections
How it works
Based on a 10 mg PT-141 vial diluted with 1 mL of bacteriostatic water, each 500 mcg injection equals 0.05 mL.
1mL / 100 units
5 units
0.050 mL
Reference Guide
Dosing Cycle
- Peptide
- PT-141
- Dosing
- 1.75mg per injection
- Dosing Frequency
- as needed, no more than once per 24 hours (max 8 doses per month)
- Cycle Duration
- on-demand use; reassess after 3 months
- Storage
- Lyophilized: store at -20°C or below, desiccated. Reconstituted: refrigerate at 2–8°C and use within 28 days; for longer storage freeze below -18°C.
Note: Triple agonist; microdose for fewer side effects
Reconstitution Tips
- Use bacteriostatic water (BAC) — contains 0.9% benzyl alcohol for preservation
- Inject water slowly — aim down the vial wall, not directly onto powder
- Never shake — gently swirl or roll the vial until dissolved
- Store properly — refrigerate at 2-8°C after reconstitution
- Use within 28 days — most reconstituted peptides remain stable for about 4 weeks
- Keep sterile — always clean vial tops with alcohol before drawing
Peptide Interactions
Research suggestions of PT-141 interactions with other common peptides and substances.
Side effects
Monitor: Be careful when combining PT-141 with Kisspeptin, Melanotan II.
Contraindications
Uncontrolled hypertension
Cardiovascular disease
Use of nitrate medications
Pregnancy or breastfeeding
Stop signs
Severe or persistent nausea/vomiting
Significant blood pressure drop or dizziness
Chest pain or irregular heartbeat
Severe headache or vision changes
Prolonged erection exceeding 4 hours
Bad signs
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Frequently asked questions
What is a peptide dosage calculator?
A peptide dosage calculator is a free tool that converts your vial size, bacteriostatic water volume, and target dose into an exact syringe draw volume. Instead of doing the reconstitution math by hand, you enter three inputs and instantly get the concentration of your solution and how many milliliters or syringeunits to draw. This calculator works for single peptide compounds and multi-peptide blends.
How do I calculate peptide dosage from a vial?
To calculate your peptide dose, divide the total peptide content of your vial in micrograms by the volume of bacteriostatic water you added in milliliters. This gives you your solution concentration in mcg/mL. Then divide your target dose by that concentration to get your draw volume. For example, a 5mg (5,000 mcg) vial reconstituted with 2mL of BAC water gives a concentration of 2,500 mcg/mL. A 250 mcg dose would require drawing 0.1mL. This calculator automates all of those steps instantly.
How much Bacteriostatic water should I add to a peptide vial?
Most people add 2mL to 3mL of bacteriostatic water per vial, but the right amount depends on the dose you want to draw and the syringe size you are using. Adding 1mL to a 5mg vial gives you a concentration of 5,000 mcg/mL, making each dose very small in volume. Adding 2mL gives you 2,500 mcg/mL, which is easier to measure on a standard insulin syringe. A general guideline is to choose a volume that puts your typical dose somewhere between 10 and 30 units on a U-100 syringe. Use the calculator above to test different water volumes and find what works for your dose.
How are peptides different from proteins?
Both are made of amino acids, but peptides are much smaller than proteins. Because of their tiny size, peptides can act like tiny messengers in the body, sending specific signals to your cells to tell them exactly what to do.
PT-141Research References
PT-141 is a fda approved compound
PT-141
PT-141 is a fda approved compound
FDA Approval Trial for HSDD
Phase 3 trials with 1.75mg subcutaneous in premenopausal women showed 24.5% improvement vs 17.2% placebo, achieving statistical significance.
2019
Male Erectile Dysfunction Clinical Trial
1-20mg intranasal showed dose-dependent erectile response, effective including in PDE5 inhibitor-resistant cases via CNS pathways.
2017
Mechanism of Action Study
In vitro and animal studies confirmed selective MC3R/MC4R binding activating sexual arousal without peripheral vasodilation.
2016
Calculate peptide dosages
Learning how to calculate a peptide dose? Use our beginner-friendly peptide dosage, blend, and accumulation calculators. Enter vial size, reconstitution volume, and target dose to get exact draw volumes instantly. No guesswork, just clear guidance that helps prevent common mistakes.
