Peptide profile

PT-141

Bremelanotide / Vyleesi / The Libido Peptide

Hormone Health

The only peptide FDA-approved for sexual dysfunction — activates desire pathways in the brain rather than simply improving blood flow.

Evidence Level

Anecdotal
Emerging
Moderate
Strong

Legal Status

Schedule 4 (Prescription)

Dosage

1.75 mg subcutaneous injection, administered 45 minutes before sexual activity (as-needed use)

Route

subcutaneous injection

How it works

A cyclic lactam analogue of alpha-MSH (melanocyte-stimulating hormone) that activates melanocortin receptors, particularly MC3R and MC4R in the central nervous system. Unlike PDE5 inhibitors (Viagra, Cialis) which work peripherally by improving blood flow, PT-141 acts centrally in the hypothalamus and limbic system — directly activating the neural circuits involved in sexual arousal and desire. This central mechanism of action means it addresses low libido and hypoactive sexual desire rather than purely physiological erectile or arousal dysfunction. It has demonstrated efficacy in both men and women.

Research summary

FDA-approved as Vyleesi (2019) for hypoactive sexual desire disorder (HSDD) in premenopausal women — the first and only centrally-acting treatment approved for this indication. Pivotal trials (RECONNECT) demonstrated statistically significant improvement in satisfying sexual events and desire scores versus placebo. Widely used off-label in men for libido enhancement and as an adjunct to conventional ED treatment where desire (not just mechanics) is the primary issue. In Australia, accessible via prescription from practitioners experienced in sexual health and hormone medicine.

Cycle duration

As-needed use — not daily administration

Stacks well with

These peptides complement PT-141's mechanism and are commonly combined in protocols.

LongevityFat Loss
Moderate

Ipamorelin + CJC-1295

The gold standard GH-releasing combination for anti-ageing, body recomposition, and sleep quality.

100–300 mcg of each peptide, before bedView
Hormone Health
Emerging

Kisspeptin-10

The upstream regulator of testosterone production — stimulates the GnRH pulse that drives LH and testosterone secretion from the brain's own signalling system.

50–100 mcg subcutaneous, 2–3 times dailyView

Supplements that pair with PT-141

These supplements directly amplify or support PT-141's mechanism of action.

SecondaryModerate

Ashwagandha (KSM-66)

Clinically validated adaptogen — reduces cortisol, supports testosterone, and improves exercise recovery.

300–600mg KSM-66 extract dailyView
CoreStrong

Zinc Bisglycinate

A foundational mineral for testosterone synthesis, immune function, and protein metabolism.

15–30mg elemental zinc dailyView

Free tool

Protein targets for your PT-141

Protein requirements vary significantly by protocol goal and activity level.

80kg

152g

Daily total

51g

Per meal (3 meals)

1.9g/kg

Per kg bodyweight

Top sources to hit 152g daily

Chicken breast (cooked)~490g hits target
Whey protein (1 scoop ~30g)~190g hits target
Salmon fillet (cooked)~610g hits target
Eggs~22 eggs hits target
Greek yoghurt (200g serve)~8 serves hits target
Lean beef mince (cooked)~590g hits target

How this connects to your protocol

Adequate protein maintains the amino acid pool required for hormone synthesis. Low protein directly impairs testosterone and IGF-1 production — the same hormones your peptide protocol is optimising.

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Targets are evidence-based estimates. Consult your practitioner for personalised advice.

Risks & side effects

Nausea and flushing — most common side effects, typically resolve within 2–4 hours
Transient blood pressure increase — screen for hypertension before prescribing
Not for use with erectile dysfunction medications without prescriber guidance
Limited long-term safety data beyond the clinical trial period
Contraindicated with cardiovascular disease — requires thorough pre-prescribing assessment

How to access in Australia

This peptide is classified as Schedule 4 in Australia, meaning it requires a prescription from an AHPRA-registered practitioner. It is typically dispensed through a licensed compounding pharmacy.

Find a prescriber

Australian clinics that prescribe PT-141 or treat related goals.

Rx

Thrive Rx

Telehealth Clinic
4.8(312)

Australia's most thorough longevity and peptide clinic — blood panel first, protocol second.

$199–$599 AUD / month Australia-wide
AHPRA-registered clinicians
Comprehensive blood panel included in membership
Ongoing biomarker tracking every 6 months
Higher price point than GLP-1 only clinics
Requires full health assessment before any prescription
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PX

Phyx

Telehealth Clinic
4.7(260)

The Home of Longevity — performance-focused peptide therapy, supplements, and Afterpay-supported plans across Australia.

$150–$500 AUD / month Australia-wide
One of the widest peptide menus in Australia — 19+ compounds available
Afterpay available — pay in 4 easy instalments
Includes hard-to-find peptides: Epitalon, MOTS-C, Oxytocin, DHEA
Newer brand — less established review base than Thrive Rx or Pilot
Premium pricing on some specialised compounds

Peptides available (19)

AOD 9604CJC 1295IpamorelinHCGMOTS-CBPC 157CJC 1295 + IpamorelinTB-500+11 more
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GL

GL Vitality Drips

Telehealth Clinic
4.6(340)

Doctor-prescribed peptides and NAD+ therapy delivered Australia-wide — nurse-led care with AHPRA-registered practitioners and licensed compounding pharmacies.

$150–$450 AUD / month Australia-wide
AHPRA-registered Australian doctors prescribe all peptides
Licensed compounding pharmacies with COA-verified products
Medical-grade cold-chain courier delivery nationwide
Smaller clinic — less brand recognition than larger platforms
Review count lower than established competitors — newer market entrant
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Medical disclaimer

The information on this page is for educational purposes only and does not constitute medical advice. All peptide and supplement therapies should be discussed with an AHPRA-registered medical practitioner before use. ProtocolHub does not prescribe, dispense, or supply any therapeutic goods. Always consult a qualified healthcare professional before starting any new health protocol.

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