PT-141 (Bremelanotide) vs Selank

Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.

PT-141 (Bremelanotide)Selank
CategoryPeptidesPeptides
Standard DoseResearch indicates 1.75 mg administered via subcutaneous injection approximately 45 minutes before anticipated sexual activity.Research indicates 250-500 mcg daily via intranasal administration (0.15% solution, 2-3 drops per nostril).
Timing45-60 minutes before anticipated sexual activity. Effects last 6-72 hours depending on individual response.Can be dosed morning through evening. Unlike Semax, Selank is calming and can be used at night.
Cycle DurationAs-needed basis. Not intended for daily use.14-21 day cycles with equal rest periods.
Evidence Levelstrong_humanmoderate_human

Mechanism

PT-141 (Bremelanotide) is a synthetic cyclic heptapeptide melanocortin analog that acts as an agonist at MC3R and MC4R melanocortin receptors, with higher affinity for MC4R. It enhances sexual desire by activating presynaptic MC4Rs on neurons in the medial preoptic area (mPOA) of the hypothalamus, increasing dopamine release — an excitatory neurotransmitter for sexual desire. Unlike PDE5 inhibitors, PT-141 works centrally through the CNS rather than peripherally on blood flow, addressing desire rather than just erectile mechanics.

Standard Dosing

Research indicates 1.75 mg administered via subcutaneous injection approximately 45 minutes before anticipated sexual activity.

Timing

45-60 minutes before anticipated sexual activity. Effects last 6-72 hours depending on individual response.

Cycle Duration

As-needed basis. Not intended for daily use.

Side Effects

  • Nausea (most common, dose-dependent)
  • Flushing
  • Headache
  • Nasal congestion (intranasal route)
  • Transient blood pressure increase
  • Skin darkening with repeated use

Contraindications

  • Uncontrolled hypertension
  • Cardiovascular disease
  • Pregnancy and breastfeeding
  • Use of other melanocortin agonists concurrently

Best Stacking Partners

Kisspeptin-10Melanotan II
B

Selank

Peptides

Mechanism

Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) is a synthetic heptapeptide analog of the immunomodulatory peptide tuftsin (from IgG heavy chain) with a Pro-Gly-Pro extension for metabolic stability. It allosterically modulates GABA-A receptors, enhancing GABA binding and GABAergic neurotransmission. Selank modifies mRNA levels of 84 genes involved in GABAergic neurotransmission in the frontal cortex, enhances enkephalinase inhibition (increasing endogenous enkephalin levels), and modulates serotonergic and noradrenergic systems to produce anxiolytic and nootropic effects.

Standard Dosing

Research indicates 250-500 mcg daily via intranasal administration (0.15% solution, 2-3 drops per nostril).

Timing

Can be dosed morning through evening. Unlike Semax, Selank is calming and can be used at night.

Cycle Duration

14-21 day cycles with equal rest periods.

Side Effects

  • Mild nasal irritation
  • Fatigue/sedation (uncommon)
  • Mild headache

Contraindications

  • Pregnancy and breastfeeding
  • Severe hepatic impairment

Best Stacking Partners

SemaxBPC-157Thymosin Alpha-1

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