Andropause (aging male)
Age-related testosterone decline and HPG-axis softening in men, typically 40+. Symptoms span libido, mood, body composition, recovery.
What changes during this transition
Total and free testosterone decline gradually from the late 30s onward, sometimes accompanied by SHBG rise (lowering bioavailable T further), reduced libido, slower recovery, sarcopenia, and mood changes. TRT (exogenous testosterone — not a peptide) is the most direct intervention; peptides relevant to this stage are either GH-axis (compensating for declining GH/IGF-1, which falls in parallel with T) or HPG-axis stimulators (kisspeptin to preserve endogenous T pathway in users avoiding TRT). PT-141 addresses libido independent of T levels. Tracking with SHBG, free T, IGF-1, fasting insulin, and lipid panel is meaningful here.
Important caveat
Don't self-diagnose age-related T decline from symptoms alone — measure total + free T, SHBG, LH, FSH, estradiol, and prolactin before starting any HPG-axis peptide. AAS use (not peptides, often co-used) suppresses LH/FSH dramatically and changes the calculus entirely.
Peptides editorially relevant to andropause (aging male)
7 peptides from the library — each evidence-tiered honestly.
- CJC-1295Tier 3
GHRH analog
Long-acting GHRH analog often paired with a GHRP. Strong PK data in humans; outcome data is limited.
- IpamorelinTier 3
GHRP / ghrelin mimetic
Selective GH-releasing peptide with minimal cortisol or prolactin elevation in early studies. Human outcome evidence is limited.
- TesamorelinTier 1
GHRH analog
FDA-approved for HIV-associated lipodystrophy. Off-label use for general fat loss is meaningfully less supported.
- KisspeptinTier 2
KISS1R agonist (hypothalamic neuropeptide)
Sits at the very top of the reproductive axis — triggers the cascade that produces sex hormones. Strong clinical-research evidence for hypogonadism and IVF use; off-label 'natural T' community use in healthy men runs ahead of the data.
- PT-141 (Bremelanotide)Tier 1
Melanocortin receptor agonist
FDA-approved as Vyleesi for premenopausal HSDD. Off-label use for male erectile function and on-demand libido is widespread but supported by far thinner evidence.
- BPC-157Tier 3
Gastric pentadecapeptide
Extensively studied in rodents for tissue healing across tendon, gut, vascular, and CNS injury models. Human evidence is essentially absent — community framing far outpaces the data.
- MK-677 (Ibutamoren)Tier 2
Non-peptide ghrelin mimetic (small molecule)
Orally bioavailable small molecule that elevates GH and IGF-1. Multiple human RCTs confirm the hormone effect; clinical-outcome benefits are far less settled.
Want this list to grow? The library is editorial — if there’s a peptide you think belongs on this page with documented or mechanistically-clear evidence, send us a note with the citation and we’ll review it under the same evidence-tier discipline as every other entry.