Peptide Half-Life Reference Chart: Verified Plasma Half-Lives, With the Human vs Animal Source Flagged

This page is a plasma half-life reference for the research peptides people actually search for, with one rule applied throughout: every value states what species it came from and what document reports it, and where no data exists we say “none published” instead of inventing a number. That rule alone changes the chart substantially. BPC-157’s commonly quoted “6 to 8 hours” is not a measured human figure and never was; the only real PK study is a rat and dog ADME paper reporting 15.2 minutes. Tesamorelin carries three different official half-lives depending on which label you open. GHK-Cu and Epitalon have no citable half-life at all, and even full-length thymosin beta-4’s published abstract gives a direction rather than a number. The deciding point is the same one that runs through this whole site: a number is only as trustworthy as the source behind it, and a purity percentage on a vial is only as trustworthy as the third-party COA you can independently look up.

Published 2026 - For research use only (RUO). Nothing here is medical advice, a dosing protocol, or a human-use recommendation. Half-life figures are pharmacokinetic parameters reported in published literature and regulatory documents, reproduced here as reference data.

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The peptide half-life chart

Sorted shortest to longest. The Model / source column is the most important column on this page.

Compound	Reported plasma half-life	Model / source	Note
BPC-157	5.27 ± 2.25 min (IV, dog); 15.2 min (IV, rat); <30 min across IV and IM in both species	Animal - rat and beagle-dog ADME study, n=6 per group [5]	No human PK study exists. The widely circulated “4-6 h” and “6-8 h” figures have no primary source we can locate
Sermorelin (GHRH 1-29)	6-7 min (IV)	Human - sermorelin acetate SPC, Irish medicines regulator [14]	The SPC wording is exact: “a plasma half life of 6-7 minutes after intravenous administration”. The 11-12 min figure quoted by secondary sources is not in that document
Tesamorelin	8 min (single SC, 2 mg/vial formulation); 11 min (single SC, 11.6 mg/vial formulation); 26 min healthy / 38 min HIV-infected (14 consecutive days SC, original 1 mg/vial label)	Human - three regulator-reviewed labels [2][3][4], corroborated by the FDA clinical pharmacology review [15]	Same molecule, three official numbers. The review independently reports 18.6 min single-dose and 37.8 min multiple-dose SC in HIV-infected patients, and 13.2 min after a single 2 mg SC dose in healthy subjects
ARA-290 (cibinetide)	Reported ~2 min to ~20 min	Uncertain - secondary sources only	No primary human PK paper located. Treat the range as unresolved, not as a fact
Epitalon (AEDG)	None published	-	No plasma PK study located. Unmodified tetrapeptides clear in minutes as a class, but class inference is not measurement
GHK-Cu	No citable primary value. Secondary sources span ~2 min to ~4 h	Disputed / unsourced	What is peer-reviewed is the age-related plasma decline: “At age 20, the plasma level of GHK is about 200 ng/mL, and by the age of 60, it declines to 80 ng/mL” [8]. That paper reports no half-life
TB-500 (acetylated fragment)	None published for the fragment	-	Do not inherit thymosin beta-4’s number. The market peptide and the full-length protein are not the same molecule
Thymosin Beta-4 (full-length, synthetic)	Dose-dependent, direction only. Half-life increased with increasing dose across single IV doses of 42, 140, 420 and 1260 mg	Human - phase 1, four cohorts of 10 healthy subjects [6]	The published abstract states the dose-dependence but reports no per-dose hour values. The tidy “0.95 h to 2.1 h” numbers circulating online are not in the public record, so this chart does not repeat them
Thymosin Alpha-1 (thymalfasin)	“Less than 3 hours” (SC)	Human - nine volunteers, three SC formulations, 3-way crossover [7]	That is the study’s own wording. The tidier “~2 h” in circulation is a downstream summary. The paper reports no accumulation across repeat SC dosing
Ipamorelin	~2 h terminal (IV infusion)	Human - phase 1 PK/PD, five dose levels, eight subjects each [13]	GH response peaked at 0.67 h then declined exponentially - the effect curve and the plasma curve are different curves
Tirzepatide	~5-6 days	Human - current FDA label [11]	Scale anchor only. The long half-life is engineered via a C20 fatty-diacid albumin binder
GLP-3 RT (GLP-class tri-agonist)	~6 days (published reference molecule)	Human - phase 1b multiple-ascending-dose trial in adults with type 2 diabetes [9]	This is the PK of the published triple-agonist reference molecule in [9], not a measurement of any vendor’s vial
Semaglutide	~1 week (145-168 h across three SC studies)	Human - systematic review of clinical PK [10]	Scale anchor only. Albumin binding again; same protraction strategy
CJC-1295 with DAC	5.8-8.1 days	Human - phase 1, healthy adults [12]	Same GHRH backbone family as sermorelin, roughly a thousand-fold longer, purely because of the DAC albumin-binding modification
KLOW / Glow / Wolverine blends	Not applicable	-	A blend has no single half-life. Each component clears on its own curve, so “the blend’s half-life” is a category error

The two approved-drug rows (tirzepatide, semaglutide) are included solely as pharmacokinetic scale anchors, so you can see what an engineered multi-day half-life looks like next to a six-minute one. They are not offered for sale here, not compared for effect, and not a substitute reference for anything else on the chart.

How to read and use this data

Half-life is a plasma parameter, not a duration of effect. This is the single most misread idea in the peptide space. BPC-157 clears rat plasma in about 15 minutes yet its studied effects in animal models are described over much longer windows. Sermorelin is gone from circulation in well under an hour, but its own SPC records that the response it provokes peaks around 30 minutes post dose and lasts 2 to 3 hours [14]. If you use half-life to predict how long something “works,” you will be wrong in both directions.

Five half-lives is the number worth memorising. Under first-order elimination, each half-life removes half of whatever remains: 50 percent gone after one, 75 after two, 87.5 after three, 93.75 after four, and 96.875 after five. The standard reference states the same thing as a band - 94 to 97 percent of a drug is eliminated after four to five half-lives [1]. The identical arithmetic runs in reverse for accumulation: repeated administration at a fixed interval climbs toward steady state and lands within a few percent of it after roughly four to five half-lives. This is textbook pharmacokinetics and it is stated here as a concept. It is not a schedule, not an interval recommendation, and not a protocol for anything.

Route changes the number. An intravenous half-life and a subcutaneous half-life are not interchangeable. Subcutaneous administration adds an absorption phase, and for some molecules absorption is slower than elimination, so the observed terminal half-life is absorption-limited rather than truly reflecting clearance. When a chart gives you one number with no route attached, it has thrown away information.

Formulation changes the number too. Tesamorelin is the cleanest illustration on this page. The original 1 mg/vial label reports 26 minutes in healthy subjects and 38 minutes in HIV-infected patients after 14 consecutive days of subcutaneous dosing [2]. The current 2 mg/vial label reports 8 minutes after a single 1.4 mg subcutaneous dose [3]. The current 11.6 mg/vial label reports 11 minutes after a single 1.28 mg subcutaneous dose [4]. All three are regulator-reviewed labels. All three describe tesamorelin. Anyone quoting one of them as “the” half-life of tesamorelin, without saying which, is not being careful. The underlying FDA clinical pharmacology review adds the detail that makes the spread make sense: in HIV-infected patients the mean elimination half-life was 18.6 minutes after a single subcutaneous injection and 37.8 minutes after multiple ones [15]. Single versus multiple dosing moves the number by roughly a factor of two on its own.

Species is not a footnote. A rat number is a rat number. Rodent clearance rates generally differ from human ones, and the direction of the difference is not reliably predictable for a given peptide. The rat and dog values in the BPC-157 row are real, well-conducted data [5]; what they are not is a human half-life, and no amount of repetition converts one into the other.

Sourcing and accuracy

Here is where each class of value on the chart comes from, and what to distrust.

Regulatory labels and SPCs (tesamorelin, tirzepatide, sermorelin). These are the strongest sources on the page. They reflect data reviewed by a regulator against a specific formulation and population. Their weakness is that labels get superseded, and old figures outlive them in secondary literature - the tesamorelin “26 minutes” is exactly that phenomenon, still the most-quoted number for the compound despite two newer labels stating single-digit and low-double-digit minutes. Note too that a single document can carry more than one figure: the current tirzepatide label’s clinical pharmacology section states an elimination half-life of “approximately 5-6 days” in patients with overweight or obesity, while its overdosage section rounds to “approximately 5 days” [11]. Neither is wrong, and the tidy “5 days” that circulates in summaries is the rounded one. This chart cites the clinical pharmacology figure and says so.

Peer-reviewed human trials and systematic reviews (thymosin beta-4, thymosin alpha-1, ipamorelin, CJC-1295 with DAC, semaglutide, the GLP-class reference molecule). Solid, but read the conditions. The thymosin beta-4 study dosed four cohorts of ten healthy subjects at 42, 140, 420 and 1260 mg intravenously and reports dose-proportional PK with half-life rising as dose rose - but the public abstract gives no per-dose hour figures, so the specific numbers you will find quoted elsewhere are not something we can verify and we do not print them as fact [6]. The thymosin alpha-1 source characterises the elimination half-life as “less than 3 hours” [7]; the tidier “2.1 hours” that circulates is a downstream summary figure, not the phrasing of the primary study. The semaglutide figure is a range, 145 to 168 hours across three subcutaneous studies, which the review itself rounds to “approximately 1 week” [10].

Animal ADME studies (BPC-157). The 2022 rat and dog study is a proper preclinical PK paper: 15.2 min mean elimination half-life after intravenous dosing in rats, 5.27 min in dogs, and under 30 minutes across intravenous and intramuscular routes in both species [5]. Flagged as animal because it is animal.

No data (Epitalon, TB-500 fragment, GHK-Cu, ARA-290). We searched for primary pharmacokinetic sources for each and did not find one. For GHK-Cu the secondary figures we encountered ranged from about 2 minutes to about 4 hours, spanning two orders of magnitude - a spread that tells you the number was never measured, only guessed at repeatedly; the peer-reviewed GHK paper most often cited for this row reports the age-related plasma decline and no half-life at all [8]. For ARA-290 the range was roughly 2 to 20 minutes with the same problem, which is why this page does not assert how fast it clears. For Epitalon, nothing. For TB-500 specifically, the human data that gets attached to it belongs to full-length thymosin beta-4, which is a different molecule from the acetylated fragment sold on the research market. Being the page that says “none published” instead of filling the cell is the entire point of this reference.

One more honest caveat that applies to every row. These are the pharmacokinetics of a defined, characterised molecule as studied in a controlled setting. They are not a property of whatever is inside a vial you bought. If the vial contains 70 percent of the labelled peptide plus 30 percent synthesis by-products, or the wrong sequence entirely, the published half-life of the intended molecule is a fact about the literature and not a fact about your material.

Why this matters for vetting a vendor

The link between a PK chart and a vendor checklist is tighter than it looks.

Notice what the “no published data” rows have in common with the worst vendor listings: a confidently stated number with nothing behind it. When a store’s product page tells you BPC-157 has a 6 to 8 hour half-life, that store has just demonstrated, in public, that it will state a specific figure it cannot source. That is the same behaviour as printing “99% pure” with no certificate, and it is a cheap signal you can check in ten seconds before you check anything harder.

The reverse is also useful. A vendor that says “no human PK data exists for this compound” is a vendor showing you its calibration. You want the same calibration applied to its purity claims.

Which is where the actual buying decision sits. Half-life is a property of the molecule; purity and identity are properties of the batch. Only one of those two is under the vendor’s control, and only one of them can be independently verified before you pay. The checks that matter are: is an independent third-party lab named, is there an accession or batch ID you can look up on that lab’s own site, does the report include both an HPLC purity figure and a mass-spec identity confirmation, and can you read all of it before checkout rather than after. The full walkthrough is at /how-to-read-peptide-coa, the accession-lookup mechanics are at /how-to-verify-peptide-coa-lookup, the failure patterns are catalogued at /peptide-vendor-red-flags, and the end-to-end vendor process is at /how-to-vet-us-peptide-vendor.

For the arithmetic that follows a verified COA - working out concentration from a labelled mass, or comparing vendors on price per milligram of actual peptide rather than per vial - see /reconstitution-calculator and /cost-per-mg-calculator.

How Pepora fits

Being an affiliate, this section is a scorecard rather than a sales pitch, and it splits.

Pepora (peporalabs.com) ships from the US and carries Freedom Diagnostics third-party COAs - a US lab running HPLC and mass spec - on four SKUs, each verifiable by search code at FreedomDiagnosticsTesting.com:

SKU	Reported purity	Accession
GHK-Cu	99.98%	Pepo2603130126
Tesamorelin	99.348%	Pepo2603130125
TB-500 / Thymosin Beta-4	99.699%	Pepo2603130123
GLP-3 RT	99.67%	Pepo2603130122

That is four SKUs, not the whole catalog, and the honest caveat matters here more than usual given what this page is about. BPC-157, Epitalon, Thymosin Alpha-1, ARA-290 and the KLOW, Glow and Wolverine blends are not currently covered by a Freedom Diagnostics report. Testing is being expanded across the catalog, but do not assume coverage that does not exist today - check the specific product page before you pay.

Note the overlap with the chart above, because it is a genuinely useful coincidence for a buyer: three of the four Freedom-covered SKUs (tesamorelin, TB-500 / thymosin beta-4, GLP-3 RT) sit on rows where the published half-life data is either well-documented human data or explicitly flagged as belonging to a related molecule rather than to the marketed peptide. Knowing exactly which molecule is in the vial is worth more on those rows than on any other, and the mass-spec identity confirmation on those COAs is the part that establishes it. GHK-Cu is the reverse case - a compound with no citable half-life at all, where a 99.98% verified COA at least settles the identity question even though the PK question stays open.

The disclosed pick

FAQ

What does peptide half-life actually mean? Elimination half-life is the time it takes for the plasma concentration of a compound to fall by 50 percent. It is a measured pharmacokinetic parameter, not a measure of how long an effect lasts. Many peptides clear from plasma in minutes while the downstream signalling they trigger runs for hours or days, so half-life tells you about the molecule’s residence in circulation and nothing more. Half-life is also route-dependent and often formulation-dependent, which is why the same peptide can carry several different official numbers.

What is the half-life of BPC-157? There is no published human pharmacokinetic study of BPC-157. The only formal PK data comes from a 2022 rat and beagle-dog ADME study, which reported a mean elimination half-life of 15.2 minutes after intravenous dosing in rats and 5.27 minutes in dogs, with under 30 minutes across intravenous and intramuscular routes in both species. The 4 to 6 hour and 6 to 8 hour figures circulating on vendor sites do not trace to any primary source we can find, and they are roughly an order of magnitude longer than the only measured values that exist.

Why do different sites list different half-lives for the same peptide? Three reasons, and all three are legitimate before you get to sloppy copying. First, route: intravenous, subcutaneous and intramuscular give different curves. Second, formulation: the original 1 mg/vial tesamorelin label states 26 minutes after 14 days of dosing, while the current 2 mg/vial and 11.6 mg/vial labels state 8 and 11 minutes after a single dose. Third, species: a rat number is not a human number. The fourth reason, which is not legitimate, is that a figure was invented once and then copied across a hundred pages with no source.

How many half-lives does it take for a compound to be essentially cleared? Under first-order kinetics, each half-life removes 50 percent of what remains, so after five half-lives about 96.9 percent is gone. The standard pharmacology reference states the same thing as a band: 94 to 97 percent of a drug is eliminated after four to five half-lives. The same arithmetic runs in reverse for accumulation, with repeated administration at a fixed interval approaching steady state after about four to five half-lives. This is standard pharmacokinetic arithmetic and is stated here as education, not as a schedule or protocol for anything.

Does a longer half-life mean a better peptide? No. Half-life is a design parameter, not a quality score. Long half-lives are engineered deliberately, usually by adding a fatty-acid chain that binds albumin, which is how the GLP-class compounds and CJC-1295 with DAC reach multi-day figures. Short half-lives are also deliberate: sermorelin and tesamorelin clear in minutes precisely so they produce a pulse rather than continuous stimulation. A number on this chart says what a molecule does in plasma, not whether the vial you are holding contains that molecule.

Which peptides on this chart have no published half-life data at all? Epitalon (AEDG) has no published plasma pharmacokinetic study we can locate. GHK-Cu has no primary human PK half-life we can cite, only secondary figures spanning roughly 2 minutes to 4 hours, which is a spread wide enough to be meaningless. TB-500 as the acetylated fragment sold on the research market has no PK study of its own; the human data belongs to full-length thymosin beta-4, and even there the published abstract reports only that half-life rose with dose, not per-dose numbers. ARA-290 is reported anywhere from about 2 to about 20 minutes with no primary paper we can point to. Blends have no single half-life by definition.

References

1. Hallare J, Gerriets V. Elimination Half-Life of Drugs. StatPearls. Treasure Island (FL): StatPearls Publishing. NCBI Bookshelf NBK554498. States that “94% to 97% of a drug is eliminated after 4 to 5 half-lives.” https://www.ncbi.nlm.nih.gov/books/NBK554498/
2. Tesamorelin for injection, original 1 mg/vial formulation, full prescribing information, 2010. US Food and Drug Administration, NDA 022505. Section 12.3 reports a mean elimination half-life of 26 minutes in healthy subjects and 38 minutes in HIV-infected patients after subcutaneous administration for 14 consecutive days. https://www.accessdata.fda.gov/drugsatfda_docs/label/2010/022505s000lbl.pdf
3. Tesamorelin for injection, 2 mg/vial formulation, prescribing information, Theratechnologies. DailyMed, US National Library of Medicine. Section 12.3: “Mean elimination half-life (t1/2) of tesamorelin was 8 minutes in healthy subjects after single dose subcutaneous administration of the 1.4 mg.” https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=3d783378-b02d-4f19-99dd-0fc91a042224
4. Tesamorelin for injection, 11.6 mg/vial formulation, prescribing information, Theratechnologies. DailyMed, US National Library of Medicine. Section 12.3: “mean elimination half-life (t1/2) of tesamorelin was 11 minutes in healthy subjects after single dose subcutaneous administration of the 1.28 mg.” https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=839334d3-8c1d-4c26-9036-2ab524a6ea75
5. He L, Feng D, Guo H, Zhou Y, Li Z, Zhang K, et al. Pharmacokinetics, distribution, metabolism, and excretion of body-protective compound 157, a potential drug for treating various wounds, in rats and dogs. Front Pharmacol. 2022 Dec 14;13:1026182. PMID: 36588717; PMCID: PMC9794587. The abstract states only that “the elimination half-life (t1/2) of prototype BPC157 was less than 30 min” across IV and IM routes in rats and beagle dogs. The specific single-IV figures quoted on this page come from the full text: Table 1 (rats, n=6) gives t1/2 15.2 min, and Table 4 (dogs, n=6) gives 5.27 ± 2.25 min. Dog IM t1/2 values in Table 6 are 20.0, 25.5 and 29.3 min across the three doses. https://pubmed.ncbi.nlm.nih.gov/36588717/
6. Ruff D, Crockford D, Girardi G, Zhang Y. A randomized, placebo-controlled, single and multiple dose study of intravenous thymosin beta4 in healthy volunteers. Ann N Y Acad Sci. 2010;1194:223-229. PMID: 20536472. Four cohorts of 10 healthy subjects at single IV doses of 42, 140, 420 or 1260 mg; abstract reports “a dose proportional response, and an increasing half-life with increasing dose” without per-dose values. https://pubmed.ncbi.nlm.nih.gov/20536472/
7. Rost KL, Wierich W, Masayuki F, Tuthill CW, Horwitz DL, Herrmann WM. Pharmacokinetics of thymosin alpha1 after subcutaneous injection of three different formulations in healthy volunteers. Int J Clin Pharmacol Ther. 1999;37(1):51-57. PMID: 10027483. Reports “the short elimination half-life of less than 3 hours.” https://pubmed.ncbi.nlm.nih.gov/10027483/
8. Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci. 2018 Jul 7;19(7):1987. PMID: 29986520; PMCID: PMC6073405. States: “At age 20, the plasma level of GHK is about 200 ng/mL (10-7 M), and by the age of 60, it declines to 80 ng/mL.” The full text contains no half-life value for GHK or GHK-Cu, which is why this page reports none. https://pmc.ncbi.nlm.nih.gov/articles/PMC6073405/
9. Urva S, Coskun T, Loh MT, et al. LY3437943, a novel triple GIP, GLP-1, and glucagon receptor agonist in people with type 2 diabetes: a phase 1b, multicentre, double-blind, placebo-controlled, randomised, multiple-ascending dose trial. Lancet. 2022;400(10366):1869-1881. PMID: 36354040. Reports that pharmacokinetics “were dose proportional and its half-life was approximately 6 days.” https://pubmed.ncbi.nlm.nih.gov/36354040/
10. Yang XD, Yang YY. Clinical pharmacokinetics of semaglutide: a systematic review. Drug Des Devel Ther. 2024;18:2555-2570. PMID: 38952487. Reports t1/2 “in the range of 145-168 h (approximately 1 week)” across three subcutaneous studies. https://pmc.ncbi.nlm.nih.gov/articles/PMC11215664/
11. Tirzepatide injection, current prescribing information, Eli Lilly and Company. DailyMed, US National Library of Medicine. Section 12.3: “The elimination half-life is approximately 5-6 days in patients with overweight or obesity, and in patients with OSA and obesity.” Section 12.1 also states that tirzepatide “contains a C20 fatty diacid that enables albumin binding and prolongs the half-life,” and the overdosage section separately rounds to “approximately 5 days.” https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=487cd7e7-434c-4925-99fa-aa80b1cc776b
12. Teichman SL, Neale A, Lawrence B, Gagnon C, Castaigne JP, Frohman LA. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805. PMID: 16352683. Reports “the estimated half-life of CJC-1295 was 5.8-8.1 d.” https://pubmed.ncbi.nlm.nih.gov/16352683/
13. Gobburu JV, Agerso H, Jusko WJ, Ynddal L. Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers. Pharm Res. 1999;16(9):1412-1416. PMID: 10496658. Five infusion dose levels, eight healthy male subjects each; dose-proportional PK with a short terminal half-life of 2 hours and GH release peaking at 0.67 hours. https://pubmed.ncbi.nlm.nih.gov/10496658/
14. Sermorelin acetate 50 microgram powder for injection, Summary of Product Characteristics, Health Products Regulatory Authority (Ireland), PA0285/006/001. Section 5.2: “Sermorelin has a plasma half life of 6-7 minutes after intravenous administration. Peak response is reached approximately 30 minutes (15-60) post dose and lasts 2-3 hours.” https://assets.hpra.ie/products/Human/16600/LicenseSPC_PA0285-006-001_13072006155719.pdf
15. Clinical Pharmacology and Biopharmaceutics Review, tesamorelin, NDA 022505. US Food and Drug Administration, 2010. Reports mean elimination half-life of 18.6 min (single SC) and 37.8 min (multiple SC) in HIV-infected patients, and 13.2 min after a single 2 mg SC dose in healthy subjects. https://www.accessdata.fda.gov/drugsatfda_docs/nda/2010/022505Orig1s000ClinPharmR.pdf

coaindex is a Pepora affiliate (peporalabs.com) and earns a commission on purchases made with the code above. This is affiliate education, not journalism, and it ranks vendors on checkable, independently verifiable third-party-COA criteria. Research use only. Not for human or veterinary use, and nothing here is medical advice.