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Skin, hair & aesthetics · FDA-approved HSDD in premenopausal women (Vyleesi)

PT-141

Bremelanotide, Vyleesi

Bremelanotide, a Melanotan II descendant. The approved drug is Vyleesi: central MC4R, not a PDE5/blood-flow drug. Nausea is common (~40%). Contraindicated in uncontrolled hypertension/CVD.

Library entry →

  • Sexual desire (labelled population)
  • MC4R agonist
Catalog fill
10 mg
Typical water
2 mL
Route
Subcutaneous
Cycle
Not a cycling compound. Limit frequency; do not treat it as a daily peptide.
Approval
FDA-approved 2019 for premenopausal HSDD.
Status
FDA-approved prescription (Vyleesi) for a specific indication.
Evidence
Labelled melanocortin agonist with an approved indication.
Research score
90 / 100

Mechanism

MC4R in CNS pathways for sexual desire and arousal; dopaminergic and related cascades — not a local vasodilator.

Safety file

Nausea very common. Flushing, headache, transient BP rise. Focal hyperpigmentation with frequent use. Do not use in uncontrolled hypertension or CVD.

  • Nausea
  • Flushing
  • Injection-site reactions
  • Headache
  • Vomiting
  • Transient BP rise

Reconstitution

2 mL bacteriostatic water yields 5 mg/mL. A 1 mg amount is 20 units.

Research amounts

As needed, not daily. Allow several hours of observation after a first small amount.

StepAmountFrequencyNotes
First research amount0.5–1.0 mgAs needed10–20 units from a 2 mL reconstitution
Upper cited amount1.5–2.0 mgAs needed30–40 units

Storage

Lyophilized
−20 °C freezer preferred; a refrigerator is also acceptable. Do not open a cold vial — wait 15–30 minutes so it does not sweat. Avoid freeze–thaw cycling.
After water
2–8 °C, dark, up to 45 days when mixed with bacteriostatic water. Mixed vials stay in their box. Sterile water (no preservative) is single-use.

Worksheet notes

  • Flushing, nausea, and blood-pressure changes are commonly reported in the literature. Start at the low end.
  • This is not a substitute for medical evaluation of sexual or cardiovascular symptoms.
  • Bacteriostatic water: 20–25 °C. Do not refrigerate the diluent.
  • Amounts on this sheet are reconstitution math for the vial, not a recommendation.

Full protocol

Titration, schedule, and handling

The complete protocol for PT-141. Where it differs from the worksheet amounts above, the worksheet reflects the NovaEvum vial.

Reconstitution

Concentration by vial size and water volume
Vial2 mL water3 mL water
10 mg5 mg/mL3.33 mg/mL
  1. Use bacteriostatic water as the diluent.
  2. Add the water slowly, letting it run down the inside wall of the vial rather than onto the powder.
  3. Swirl gently to mix, then leave it to dissolve. Do not shake.
  4. Give it a few minutes. The finished solution should be clear and colourless.

Protocol

Route: Subcutaneous, on demand

Standard protocol (subcutaneous, on demand)

  • 1 mg to 2 mg, taken at least 45 minutes before activity, not on a daily schedule
  • Start at the low end (1 mg) the first time to gauge nausea
  • At a 2 mL fill on a 10 mg vial (5 mg/mL), 1 mg is a 0.2 mL draw (20 units)

Use occasionally, do not stack

  • This is an as-needed peptide, not a daily one
  • Do not combine with Melanotan-2 or Melanotan-1; they act on the same melanocortin system
  • Space doses out; it is not meant for back-to-back daily use

Dosing detail

  • 1 mg to 2 mg, about 45 minutes before activity. Used on demand, not daily.
  • Start at 1 mg to assess nausea, which is the main side effect, along with facial flushing.
  • Works through the nervous system for libido rather than on blood flow like the ED drugs.
  • Do not stack with MT-2 or MT-1 (same receptor family).

Duration

  • Used occasionally, on demand, rather than in a continuous cycle.

Notes

  • Also called bremelanotide. Works on the nervous system for libido rather than on blood flow.
  • Nausea and facial flushing are the common effects and ease at lower doses.
  • Inject subcutaneously.

Storage and handling

  • Keep the powdered (lyophilized) vial in a cool, dark place. Refrigerate it for longer-term storage before mixing.
  • Once reconstituted and refrigerated at 2–8 °C away from light, use the vial within 90 days.
  • Do not freeze a reconstituted vial, and keep it away from heat and sunlight.
  • If the solution turns cloudy, develops floating particles, or shows any other sign of degradation, stop using that vial.