Peptide half-life determines dosing frequency, steady-state kinetics, and clinical utility. This table compiles plasma half-life data for over 30 peptides, organized by duration class from ultra-short (<15 minutes) to ultra-long (>48 hours). Half-life values reflect native peptide pharmacokinetics unless otherwise noted.

Half-Life Classification

Category	Half-Life	Dosing Frequency	Examples
Ultra-short	<15 minutes	Continuous infusion	Insulin (IV), GHRH, TRH, GnRH
Very short	15–60 minutes	4–6× daily	Oxytocin, VIP, α-MSH, PTH(1-34)
Short	1–4 hours	2–4× daily	Exenatide, GIP, GLP-1, insulin lispro
Medium	4–12 hours	1–2× daily	Liraglutide, insulin glargine U-100
Long	12–48 hours	Once daily	Insulin glargine U-300, dulaglutide
Very long	>48 hours	Once weekly to monthly	Semaglutide, insulin degludec

Detailed Half-Life Table

Insulins

Peptide	Half-Life	Route	Duration of Action	Peak Time	Clinical Significance
Insulin (IV)	4–6 min	IV	30–60 min	Immediate	IV bolus only
Insulin lispro	3–5 hrs	SC	3–5 hrs	30–90 min	Rapid-acting, mealtime
Insulin aspart	3–5 hrs	SC	3–5 hrs	30–90 min	Rapid-acting, mealtime
Insulin glulisine	3–5 hrs	SC	3–5 hrs	30–90 min	Rapid-acting, mealtime
Insulin NPH	8–12 hrs	SC	12–18 hrs	4–8 hrs	Intermediate, biphasic
Insulin detemir	12–16 hrs	SC	18–24 hrs	6–10 hrs	Long-acting
Insulin glargine U-100	12–16 hrs	SC	~24 hrs	8–12 hrs	Long-acting, peakless
Insulin glargine U-300	19–26 hrs	SC	30–36 hrs	12–18 hrs	Extended long-acting
Insulin degludec	>42 hrs	SC	>42 hrs	10–12 hrs (flat)	Ultra-long, lowest variability

GLP-1 Receptor Agonists

Peptide	Half-Life	Route	Duration	Peak Time	Clinical Significance
GLP-1(7-36)	2–5 min	IV	Minutes	Immediate	Native incretin
Exenatide	2–4 hrs	SC	6–8 hrs	2–3 hrs	Short-acting GLP-1 RA
Liraglutide	13 hrs	SC	24 hrs	8–12 hrs	Once-daily GLP-1 RA
Semaglutide	165 hrs (7 days)	SC	~7 days	1–3 days	Once-weekly GLP-1 RA
Dulaglutide	96 hrs (4 days)	SC	~4 days	2–3 days	Once-weekly GLP-1 RA
Oral semaglutide	165 hrs	Oral	~7 days	1–3 days	Oral GLP-1 RA

GH Axis Peptides

Peptide	Half-Life	Route	Duration	Peak Time	Clinical Significance
GHRH(1-44)	5–10 min	IV	30–60 min	5–15 min	Pulsatile GH release
Sermorelin	12–15 min	IV/SC	60–90 min	15–30 min	GHRH analog
GHRP-6	15–20 min	SC/IV	60–90 min	15–30 min	GH secretagogue
GHRP-2	15–20 min	SC/IV	60–90 min	15–30 min	GH secretagogue
Ipamorelin	2 hrs	SC	4–6 hrs	30–60 min	Selective GH secretagogue
CJC-1295 (no DAC)	6–8 hrs	SC	12–24 hrs	1–4 hrs	GHRH analog
CJC-1295 DAC	6–8 days	SC	~7 days	6–12 hrs	Long-acting GHRH
MK-677	1–2 hrs	Oral	6–8 hrs	1–2 hrs	Oral GH secretagogue
Tesamorelin	20–30 min	SC	2–4 hrs	30–60 min	GHRH analog
hGH	15–20 min	IV	1–2 hrs	1–3 hrs	Growth hormone

Reproductive Hormones

Peptide	Half-Life	Route	Duration	Peak Time	Clinical Significance
GnRH	2–4 min	IV	15–30 min	2–5 min	Pulsatile gonadotropin release
Leuprolide	3–4 hrs	SC/IM	24 hrs	4–8 hrs	GnRH agonist depot
Triptorelin	3–5 hrs	SC/IM	24–48 hrs	4–12 hrs	GnRH agonist depot
Goserelin	2–4 hrs	SC implant	28 days	N/A (depot)	GnRH agonist implant
Oxytocin	3–5 min	IV	15–30 min	1–3 min	Uterotonic
Desmopressin	1–2 hrs	SC/IV	6–12 hrs	1–2 hrs	Antidiuretic

Other Therapeutic Peptides

Peptide	Half-Life	Route	Duration	Peak Time	Clinical Significance
Somatostatin	1–3 min	IV	10–20 min	1–2 min	Hormone inhibitor
Octreotide	1.5–2 hrs	SC	6–8 hrs	30–60 min	Somatostatin analog
Lanreotide	23–30 days	SC depot	28 days	N/A (depot)	Somatostatin analog
Teriparatide	4–8 min	SC	30–60 min	15–30 min	Bone formation
Calcitonin (salmon)	10 min	SC/IM	2–4 hrs	15–30 min	Bone resorption
BPC-157	Hours (est.)	SC/oral	4–8 hrs	30–60 min	Cytoprotective
Thymosin β4	2–4 hrs	SC	6–12 hrs	1–2 hrs	Tissue repair
GHK-Cu	1–2 hrs	SC/topical	4–8 hrs	30–60 min	Copper peptide

Factors Affecting Peptide Half-Life

Factor	Effect on Half-Life	Mechanism
Fatty acylation	Increases 10–100×	Albumin binding, injection site depot
PEGylation	Increases 5–50×	Renal filtration resistance
DPP-4 resistance	Increases 10–100×	Enzymatic stability (GLP-1 analogs)
Albumin binding	Increases 5–20×	Reduced renal clearance
pH-dependent precipitation	Increases 3–10×	Slow dissolution (insulin glargine)
Multi-hexamer formation	Increases 10–50×	Slow dissociation (insulin degludec)
Cyclization	Increases 2–5×	Protease resistance
D-amino acid substitution	Increases 3–10×	Protease resistance

Half-Life and Dosing Implications

Half-Life	Steady State	Missed Dose Impact	Washout Time
<1 hour	3–4 hours	Rapid loss of effect	<4 hours
1–4 hours	6–12 hours	Significant effect loss	6–12 hours
4–12 hours	1–2 days	Moderate effect loss	1–2 days
12–48 hours	2–4 days	Mild effect loss	2–4 days
>48 hours	1–2 weeks	Minimal effect loss	1–2 weeks

Related Pages

• Peptide Half-Life
• Peptide Pharmacokinetics
• Peptide Molecular Weight Table
• Peptide Dosing Reference
• Peptide Stability Data