Protocol

Running a GLP-1 protocol

What the record holds about the schedule: how often each of these is given, what its half-life is, and whether anything accumulates between doses.

Last updated 12 August 2026

14compounds in this class

12with a half-life on file

9with a schedule on file

9curves drawn

12 of 14 hold a half-life measurement. A curve needs that and a schedule, which is why 9 lines are drawn below and 5 members appear in the table with no line at all.

Fourteen compounds act at the GLP-1 or amylin receptor, and they are run on schedules three orders of magnitude apart — from twice a day to once a week. The table states the interval and the half-life the record holds for each, and the charts show what those two numbers do together. Where either is missing the row says so; nothing here is filled in from a comparable compound.

The schedule on file

Read the last column first. Four kinds of thing get printed as a dose in this category and they are not the same kind of fact: an approved label, a trial protocol, a figure the community circulates, and arithmetic done on an animal study. What each chip means.

Every member of this class, including the ones no curve could be drawn for.
Compound	Schedule on file	Half-life	Accumulation	Where the schedule comes from
Semaglutidecurve	weekly0.1-2.4 mg weekly	1 wkhuman, SC	2.00×the steady peak is 2.00 times the first	label OZEMPIC/RYBELSUS
Retatrutidecurve	weekly0.25-12 mg weekly	6 dhuman, SC	1.80×the steady peak is 1.80 times the first	trialThe escalating 1 to 12 mg schedule is a phase 2 trial design, not an approved regimen.
Tirzepatidecurve	weekly0.5-15 mg weekly	5 dhuman, SC	1.61×the steady peak is 1.61 times the first	label MOUNJARO
Amylincurve	weeklyPetrelintide: 0.04-9.0 mg SC weekly; Eloralintide: 1-3 mg SC weekly	20 minhuman, SC	noneeach dose has cleared before the next arrives	trialThe schedule on file is petrelintide's phase 2 range. Native amylin is not administered.
Liraglutidecurve	dailyStart: 0.6 mg/day, titrate to 3.0 mg/day	13 hhuman, SC	1.39×the steady peak is 1.39 times the first	label Victoza
Lixisenatidecurve	daily10 - 20 mcg/day	3 hhuman, SC	noneeach dose has cleared before the next arrives	labelAdlyxin was approved and the schedule is its labelled one, but the standalone label is no longer published by DailyMed or openFDA — the only lixisenatide document still available is the Soliqua combination label. Nothing is on file here to link.
Exenatidecurve	twice daily5 - 10 mcg, 2x/day	2.4 hhuman, SC	noneeach dose has cleared before the next arrives	label Byetta
Exendin-4curve	twice daily5-10 µg BID (as Exenatide); 0.01-0.3 µg/kg single dose	1.8 h1.7 h to 1.9 hmice, SC	noneeach dose has cleared before the next arrives	circulatedThe naturally occurring peptide exenatide is the synthetic form of. The schedule on file is the one passed around for the research peptide, not the Byetta label.
Pramlintidecurve	twice daily120 mcg, 2x/day (diabetes)	48 minhuman, SC	noneeach dose has cleared before the next arrives	label SYMLINPEN
Cagrilintidesingle dose	no schedule on fileTitrate to 2.4 mg/week	1.1 wk6.6 d to 1.2 wkhuman, SC	—needs a half-life and an interval from the same record	trial
Dulaglutidesingle dose	no schedule on file0.75 - 1.5 mg/week	5 dhuman, SC	—needs a half-life and an interval from the same record	label Trulicity
GLP-1 (7-36)single dose	no schedule on fileSC infusion: 1.5 pmol/kg/min; Oral: 0.5-4.0 mg; Nasal: 300 µg	2 minhuman, route not stated	—needs a half-life and an interval from the same record	trialAn infusion used in physiology studies. There is no take-home schedule to state.
Survodutideschedule only	no schedule on fileTitrate to 6.0 mg/week	not on file	—needs a half-life and an interval from the same record	trial
VK2735schedule only	no schedule on fileTitrate to 15 mg/week	not on file	—needs a half-life and an interval from the same record	trial

What the schedule does over time

Each line is one compound's amount in the body as a percentage of its own peak, from the first dose onwards. Compounds share a chart only when they share a dosing interval, because that is the only comparison the shape supports. 4 compounds build between doses; the multiplier is in the table above.

One dose every 1 wk — 4 compounds, four doses shown, each normalised to its own peak.

Semaglutide half-life 1 wk, builds to 2.00×
Retatrutide half-life 6 d, builds to 1.80×
Tirzepatide half-life 5 d, builds to 1.61×
Amylin half-life 20 min, no accumulation

One dose every 24 h — 2 compounds, four doses shown, each normalised to its own peak.

Liraglutide half-life 13 h, builds to 1.39×
Lixisenatide half-life 3 h, no accumulation

One dose every 12 h — 3 compounds, four doses shown, each normalised to its own peak.

Exenatide half-life 2.4 h, no accumulation
Exendin-4 half-life 1.8 h, no accumulation
Pramlintide half-life 48 min, no accumulation

What the curves do not model

One half-life was measured in an animal. Exendin-4 (mice). Small mammals clear peptides faster than people do, so that curve is the fastest plausible shape rather than the expected one. The species is on every row above and on the compound's own record.

The rise is not modelled. No absorption rate constant is on file for anything here, so every dose appears at full height the instant it is given. A real subcutaneous injection takes hours to peak. The decay is measured; the vertical line at each dose is a placeholder for a shape there is nothing to draw.

The axis is percent of each compound's own peak, and it is not a blood level. No volume of distribution is on file for anything on this page, so no curve here can carry a concentration. Two lines both at 50% are two compounds each at half of their own maximum — not two equal amounts of anything, and not a comparison of potency.

Combining within this class

Only the pairings somebody wrote a rule for are listed. A pairing that is absent is absent from our records, which is a statement about the records and not about safety. The full grid, including every pairing with nothing on record, is in the stack checker.

Two GLP-1-receptor agonists togethercaution

Two GLP-1-receptor agonists overlap at the receptor and their GI effects (nausea, delayed gastric emptying) are additive. The multi-agonists (tirzepatide, retatrutide) already contain a GLP-1 arm.

class rule — receptor duplication with additive adverse-effect profile.

GLP-1-receptor agonist with amylin analogcaution

Both slow gastric emptying and suppress appetite, so GI effects stack. The combination is under formal study (cagrilintide with semaglutide), which is a reason it is watched, not a reason it is routine.

class rule — additive GI burden; the combination is in clinical trials, not established practice.

Two amylin analogs togethercaution

Two amylin analogs drive the same receptor.

class rule — receptor duplication.

What the evidence says, separately

This page is about the schedule. It says nothing about whether any of it works — that is graded row by row against a named condition, and it lives on the goal pages, each of which opens with how many compounds were checked before it says which earned a row.

What this page does not say

It reports the schedules on file and what the measured half-lives imply about them. It does not recommend a compound, a dose, an interval or a combination, and a schedule appearing here is a record that somebody publishes it rather than a reason to run it. Three of the four source classes are not approvals of anything.

Lay this out as a week

The planner takes a list of compounds and turns it into administration days, with the vial maths and the same-syringe question answered per pairing.