Peptides for libido and sexual function

The melanocortin peptides, including one that made it all the way through FDA approval. This is a use case where a peptide genuinely cleared the bar — and where the gray-market version of that same peptide did not.

Ranked by strength of evidence

  1. S
    PT-141 (Bremelanotide)

    Increases sexual desire and reduces desire-related distress (HSDD) in premenopausal women

    FDA-approved as Vyleesi for this exact indication.

    Read the evidence →
  2. S
    Melanotan II

    Triggers erections and increases sexual desire

    A well-documented effect — and the reason PT-141 was developed from it.

    Read the evidence →
  3. S
    Kisspeptin

    Modulates sexual brain processing and increases arousal in men with low sexual desire

    A real randomized trial — by intravenous infusion, in an MRI scanner, with brain activity as the primary endpoint.

    Read the evidence →
  4. B
    PT-141 (Bremelanotide)

    Improves erectile dysfunction or low libido in men

    The approval covers premenopausal women; the male use is less established.

    Read the evidence →
  5. B
    HCG

    Raises testosterone in men who are not on testosterone replacement therapy

    A prescription drug, used off-label as a testosterone route. The supporting data is a 20-man series with no control group.

    Read the evidence →
  6. C
    Oxytocin

    Improves sexual function, desire, or orgasm

    The crossover trial that tested this found placebo did slightly better on every measure.

    Read the evidence →

The honest read

PT-141 is one of the clearest wins in the whole catalog: a peptide that ran the trials and got approved for a real indication. That approval covers the prescribed product, Vyleesi, obtained through a prescriber.