PT-141

About

PT-141, also known as bremelanotide, is a modified synthetic derivative of alpha-melanocyte-stimulating hormone (alpha-MSH) that acts on the melanocortin system, with high affinity for the MC4 receptor. Derived from earlier melanocortin research, it was approved by the FDA in 2019 (trade name Vyleesi) for hypoactive sexual desire disorder (HSDD) in premenopausal women. Research has also examined its effects on sexual arousal in men.

Research Applications

• Sexual function
• Hypoactive sexual desire disorder
• Anti-inflammatory melanocortin activity

Mechanism of Action

PT-141 is an agonist of the melanocortin receptors with high affinity for MC4R, the stimulation of which is associated with increased sexual desire and arousal in both men and women.

Molecular Info

Class

Peptide

Structure

Synthetic derivative of alpha-MSH (bremelanotide)

Target

Melanocortin receptors, with high affinity for MC4R

Primary research areas

Sexual desire and arousal

Dosing Guidance

Range

Clinical references cite 1.75 mg subcutaneously roughly 45 minutes before anticipated activity, with 1.25 mg also reported as effective.

Frequency

Clinical references describe self-administration no more than once per day, up to about eight times per month.

Timing

Clinical references describe administration roughly 45 minutes before anticipated sexual activity.

Cycle length

Cycle length is not consistently defined across the available research references.

Notes

These details are educational context only. Protocol values are examples and should not be treated as medical instructions.

Known Risks

• Injection-related side effects
• Temporary increases in blood pressure
• Nausea reported

Regulatory & Evidence Status

Evidence level

Well studied within its approved indication; other uses are investigational.

FDA status

Approved (Vyleesi, 2019) for hypoactive sexual desire disorder in premenopausal women; other uses, including in men, are investigational.

Availability

Prescription medication.

Standard PT-141 Protocol

Example calculation values using a 10 mg vial, 2 mL bacteriostatic water, and a 1.75 mg (1750 mcg) target amount.

Vial

10 mg

Water

2 mL

Target

1750 mcg

Syringe

U-100 · 100 units

These example values cover reconstitution math only; scheduling, route, and administration decisions are not included.