Protocol·One
Editorial reference, not medical advice. Some of what's on this page is for compounds the FDA hasn't approved. Some is off-label use of approved drugs. None of it replaces a real prescriber. Read for context. Don't self-prescribe.

PT-141 · Dosing

How PT-141 Is Actually Dosed

What does a real PT-141 (bremelanotide / Vyleesi) dose schedule look like?

A-Tier Sexual Health FDA-approved

The plain-English version

PT-141 is on-demand, not daily. Inject 1 to 1.75mg under the skin about 2 to 8 hours before activity. Most people start with 1mg to test how their body reacts. Cap is 1.75mg per dose, max 8 doses per month. Always with a doctor.

Route: subcutaneous injection, intranasal. Evidence tier for the dose: FDA-approved. FDA-approved with multiple randomized trials behind it. The strongest evidence tier in this matrix.

The dose at a glance

What's typical What's the max in research
Starting dose: 1 mg subQ (under-the-skin shot) as a first-time test dose, 2 to 4 hours before planned activity. This lets you see how your body reacts to nausea and flushing before going higher. Max observed in research: 1.75 mg per dose, max 8 doses per month, with at least 24 hours between doses. Going higher does not increase desire effects but does increase nausea and blood-pressure response.
Maintenance dose: 1.5 to 1.75 mg subQ as needed, 2 to 8 hours before activity. Vyleesi (the FDA-approved auto-injector) is a fixed 1.75 mg dose.
Frequency: As needed only. Not daily, not on a schedule. Minimum 24 hours between doses. Half-life: About 2 hours. Effect on desire and arousal can last 6-12 hours despite the short half-life because the mechanism is receptor-driven in the brain.

Titration (how to ramp the dose)

First dose: 1 mg to assess tolerance. If tolerated, future doses 1.5 to 1.75 mg. No long titration ladder - this is on-demand dosing.

Cycle length and time off

On cycle: Not applicable - PT-141 is used per-event, not in cycles.

Off cycle: Not applicable, but no more than 8 doses per 30 days.

Timing notes: Most users inject 2-4 hours pre-activity. Some need closer to 6-8 hours. Effect can persist next day. Avoid alcohol around dosing - amplifies nausea and flushing.

What's commonly prescribed (per published protocols and clinical write-ups)

Branded Vyleesi is a 1.75 mg pre-filled auto-injector pen, prescribed by gynecologists and primary care for premenopausal women with HSDD. Off-label scripts (men, post-menopausal women, ED) come from compounding pharmacies and telehealth (Hims, Hers, sexual-health specialty clinics) - usually a multi-dose vial in mg/mL concentration. Intranasal (nose-spray) PT-141 was the original delivery in early trials but was abandoned due to blood-pressure concerns; some research-chem vendors still sell it but injection is now the standard.

Source: prescribing labels, published protocols, and clinical write-ups. We have not independently tested each prescriber pattern.

Reconstitution (mixing the vial)

Lyophilized 10 mg vials reconstitute with exactly 1 mL of bacteriostatic water (sterile water with preservative, the kind compounding pharmacies sell for reconstituting peptides). At 10 mg per 1 mL, every 0.1 mL on the syringe equals 1 mg. If your pharmacy filled the vial with a different volume, recalculate from the mg/mL printed on your vial label - not from this page. Store in fridge. Use within 30 days. Vyleesi pens come pre-loaded - no reconstitution.

Reconstitution = mixing freeze-dried (lyophilized) powder with bacteriostatic water (sterile water with preservative) so you can draw a dose into a syringe.

Where to get it

Honest take on where to source this peptide. Open the free account first; that's how we get credited even if you skip the code at checkout.

FDA-approved bremelanotide

Vyleesi (via specialty pharmacy)

Fits: You want the FDA-approved version of PT-141 (Vyleesi) for premenopausal HSDD, you have a prescriber, and you'd rather not be in the gray market.

Watch: Insurance coverage is patchy and the cash price is high. Specialty pharmacy routes vary by region.

We are evaluating this source.

Compounded peptide vendor

Limitless Biotech

Fits: You already know what research-grade peptides are and you've decided this is the route you want. Limitless is the second vendor we have an affiliate link with for this category; we earn a commission if you buy through it.

Watch: Limitless's products are labeled "For Research Only" and are not FDA-approved for human use. The FDA has been actively issuing warning letters against vendors in this category in 2025 and 2026. Limitless is not a 503A or 503B compounding pharmacy. If you want a prescribing doctor and a real pharmacy, this is not that route.

Step 1 Shop Limitless Biotech ->

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Affiliate relationships are disclosed per FTC rules. Editorial take is independent of any commercial relationship; we only recommend what we'd actually use.

Drug interactions to watch

  • Blood pressure medications: PT-141 raises systolic blood pressure 5-10 mmHg for several hours. Discuss with cardiologist if on antihypertensives.
  • Naltrexone and other oral medications: PT-141 may delay absorption. Separate by several hours.
  • Alcohol: amplifies nausea and flushing. Avoid heavy drinking around dosing.

Who should not take this (contraindications)

  • Uncontrolled hypertension (high blood pressure).
  • History of cardiovascular disease - particularly recent heart attack or stroke.
  • Pregnancy and breastfeeding.
  • Known hypersensitivity to bremelanotide.

Common side effects

  • Nausea (40 percent of users in RECONNECT trial). Often the limiting factor.
  • Flushing - face and chest go warm and red.
  • Headache.
  • Injection-site reaction (mild redness, itch).
  • Temporary darkening of skin and gums (focal hyperpigmentation) with frequent dosing.

Serious side effects (call a doctor)

  • Significant blood pressure rise (5-10 mmHg systolic, up to 24 hours).
  • Severe nausea or vomiting requiring care.
  • Allergic reaction including angioedema - rare, get help immediately.
  • Priapism (painful erection over 4 hours) - rare in PT-141 use, but go to ER if it happens.

What to monitor while you're on it

  • Blood pressure check before first use, and again after 4-6 doses.
  • Skin check every 6 months for hyperpigmentation if dosing more than 4-5 times per month.
  • Dose-frequency log - capping at 8 per month is the rule, not a suggestion.

How to stop

Just stop. No taper needed. Skin pigmentation changes fade over weeks to months.

Where this dosing comes from

  • RECONNECT trial (Obstetrics and Gynecology, 2019)
  • FDA prescribing information for Vyleesi (2019)
  • Bremelanotide off-label dosing protocols (sexual medicine specialty clinics, 2020-2025)
  • Reddit r/PT141 community consensus (anecdotal but consistent)

Where these doses come from

These doses come from FDA-approved prescribing labels for PT-141. The protocols are well-characterized in the RECONNECT trials for premenopausal HSDD. Standard medical practice.

Always work with a real prescriber. Don't self-prescribe.

Safety reminder: None of this replaces a doctor. Peptides are gray-market in the US for most uses. Talk to a real prescriber before you change anything.

Where to go next

None of this replaces a doctor. Peptides are gray-market in the US for most uses. Talk to a real prescriber before you change anything.

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