Peptide calculators

BPC-157

200-500 mcg · 2x daily (morning and evening)

15-amino acid peptide derived from human gastric juice (Sikiric, J Physiol Paris 1993). Studied for tendon, ligament, muscle, and gut repair. Plasma half-life is under an hour in rodent PK (Sikiric, Curr Pharm Des 2010, PMID 20166983); the 2x daily protocol is based on pharmacodynamic effect, not drug persistence. No published human PK.

TB-500

2-5 mg · 2x weekly

Synthetic fragment of thymosin beta-4. Studied for tissue repair, wound healing, and inflammation reduction. No published human PK for the synthetic peptide; the listed half-life is a community estimate from endogenous Tβ4 kinetics (Mora, Ann N Y Acad Sci 2007).

Semaglutide

250-2400 mcg · 1x weekly

GLP-1 receptor agonist (94% structural homology to human GLP-1, Lau J Med Chem 2015, PMID 26308095). Reduces appetite and slows gastric emptying. Dosed weekly with gradual titration up from 0.25 mg per the Wegovy label (FDA 2024). STEP 1 trial (Wilding NEJM 2021, PMID 33567185) reported ~14.9% mean weight loss at 68 weeks on 2.4 mg.

Retatrutide

2-12 mg · 1x weekly

Investigational triple GIP/GLP-1/glucagon receptor agonist from Eli Lilly. Phase 2 trial (Jastreboff, NEJM 2023, PMID 37366315) reported up to ~24% mean body weight loss at 12 mg weekly over 48 weeks. Titrate from 2 mg to reduce GI side effects. Phase 3 TRIUMPH program is ongoing.

Tirzepatide

2.5-15 mg · 1x weekly

Dual GIP/GLP-1 receptor agonist. Dosed weekly with titration starting at 2.5 mg per the Mounjaro/Zepbound labels (FDA 2024). SURMOUNT-1 (Jastreboff NEJM 2022, PMID 35658024) reported ~20.9% mean weight loss at 15 mg/72 weeks; SURPASS-2 (Frias NEJM 2021, PMID 34170647) showed stronger glycemic + weight effects vs semaglutide head-to-head.

AOD-9604

250-500 mcg · 1x daily

Modified HGH fragment (amino acids 177-191). Targets fat metabolism without the growth-promoting effects of full HGH; lipolytic activity in adipocytes was shown by Heffernan in rodent models (Endocrinology 2001, PMID 11713213). The Metabolic Pharmaceuticals Phase 2b obesity trial reported in 2007 did not show significant weight loss vs placebo at 1 mg/day, and AOD-9604 has never gained drug approval; clinical efficacy in humans remains unproven.

MOTS-c

5-10 mg · 3-5x weekly

Mitochondria-derived peptide encoded in mtDNA. Studied for metabolic regulation, exercise mimicry, and insulin sensitivity. Human dosing is not established in published trials; the range below reflects community protocols, not clinical data.

Ipamorelin

100-300 mcg · 1-3x daily (fasted AM

Selective ghrelin receptor agonist. Triggers pulsatile growth hormone release without raising cortisol or prolactin (Raun, Eur J Endocrinol 1998, PMID 9849822), which is why it gets paired with CJC-1295 instead of older GHRPs. Human PK reports ~2 h half-life (Gobburu, Pharm Res 1999, PMID 10496658).

CJC-1295 / Ipamorelin

200-300 mcg · 1x daily before bed

GHRH + secretagogue combo. Stimulates pulsatile growth hormone release. The 0.5 h half-life reflects the no-DAC ('Mod GRF 1-29') CJC-1295 component (Frohman, J Clin Invest 1986); Ipamorelin itself runs ~2 h (Gobburu, Pharm Res 1999). The DAC variant of CJC-1295 has a half-life of ~6–8 days but is not in this combo. Studied for GH output, sleep quality, and recovery.

Sermorelin

200-500 mcg · 1x daily before bed

GHRH analog containing the first 29 amino acids of native GHRH. Stimulates natural GH production. Very short serum half-life ~11-12 min (Walker, Clin Interv Aging 2006, PMID 18046908). GH pulse peaks ~15-60 min post-injection, then drops fast.

HGH

200-4000 mcg · 1x daily

Recombinant human growth hormone (somatropin). Adult GH-deficiency replacement is typically 0.2-0.6 mg/day (~0.6-1.8 IU) per AACE 2019 guidelines (Yuen, Endocr Pract 2019, PMID 31760818). Doses above ~2 IU/day are supraphysiologic and used off-label for body composition. WHO IS 98/574 reference standard: 3 IU per mg somatropin, so 1 IU ≈ 333 mcg. Contraindicated in active malignancy, proliferative retinopathy, and acute critical illness (Genotropin USPI §4; Takala, NEJM 1999, PMID 10477776 for ICU mortality signal).

GHK-Cu

200-600 mcg · 1x daily

Naturally occurring copper tripeptide. Almost all clinical evidence is topical; subcutaneous dosing is not established in human trials and the SC range below is extrapolated from anecdotal protocols. In cultured fibroblasts, GHK-Cu raised collagen type 1 expression (Maquart/Pickart, FEBS Lett 1988, PMID 3169264). Studied for skin remodeling, wound healing, and hair growth.

PT-141

500-1750 mcg · As needed

Melanocortin receptor agonist studied for sexual dysfunction. Acts on the CNS, not the vascular system. FDA-approved as Vyleesi at 1.75 mg SC for HSDD in premenopausal women (bremelanotide USPI, FDA 2019). Contraindicated in uncontrolled hypertension, known cardiovascular disease, and pregnancy (Vyleesi USPI §4-§5.1, §8.1). Reduces oral naltrexone exposure ~60%; avoid in patients on naltrexone for opioid use disorder (Vyleesi USPI §7.1).

DSIP

100-300 mcg · 1x daily

Neuropeptide studied for promoting delta-wave sleep. May normalize sleep architecture and speed up sleep onset.

Selank

250-750 mcg · 1-2x daily

Synthetic tuftsin analog. Studied for anxiolytic and nootropic effects. Developed at the Institute of Molecular Genetics (Russian Academy of Sciences). Published clinical work is almost entirely intranasal; the subcutaneous route is not in peer-reviewed trials.

Semax

200-600 mcg · 1-2x daily

Synthetic ACTH(4-10) analog. Studied for cognitive enhancement, neuroprotection, and BDNF upregulation. Developed in Russia. Published clinical work is almost entirely intranasal; the subcutaneous route is not in peer-reviewed trials.