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What to Expect

Will PT-141 darken my skin or freckles?

Updated 2026-05-05

Yes, PT-141 can cause focal hyperpigmentation - dark patches on the face, gums, or breasts - especially with frequent use. This is because PT-141 acts on melanocortin receptors that also control skin pigment cells. In the Vyleesi trials, about 1% of patients reported this side effect. The risk appears higher with more frequent use and in people with darker baseline skin tone. New darker freckles or blotchy spots may fade after stopping but are not guaranteed to fully reverse. Talk to your provider about what is right for you.

IfIf you notice new dark patches on your face, gums, or chest
Thenthen pause and check in with your provider - pigment changes can fade but are not guaranteed to fully reverse
IfIf you have a darker skin tone or a history of melasma
Thenthen your risk of hyperpigmentation may be higher, so talk to your provider before starting
IfIf you stop PT-141 and pigmentation does not fade in 6-12 months
Thenthen ask a dermatologist about treatment options
IfIf you notice pigment changes with more frequent use
Thenthen talk to your provider, since more frequent use is linked to more pigment changes
Key facts
  • PT-141 binds the melanocortin-1 receptor (MC1R), which is the same receptor that triggers melanin production
  • About 1% of phase 3 patients reported focal hyperpigmentation in the Vyleesi trials
  • Risk appears higher in people with darker baseline skin tone and with more frequent use
  • Pigmentation changes are typically focal (face, gums, breasts) rather than total-body tanning
  • Reversibility is variable - some fade after stopping, some do not
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