What is the tirzepatide dosing schedule used in the research?

The trials and FDA label start tirzepatide at 2.5 mg once weekly for four weeks as an initiation dose, then escalate by 2.5 mg no sooner than every four weeks as tolerated through 5, 7.5, 10, 12.5 and a maximum of 15 mg weekly. These figures are reproduced as a laboratory research reference; they are not a human dosing protocol or medical advice.

What is tirzepatide's half-life?

The FDA clinical pharmacology review reports an elimination half-life of approximately 5 days (about 120 hours), which is why once-weekly administration is the standard interval and why steady-state is approached over roughly four to five weeks. A missed dose can generally be taken within about four days before the schedule resets.

Does Titan sell tirzepatide?

No. Titan does not stock tirzepatide, which is a prescription medicine. The compound Titan supplies in the same incretin class is retatrutide, a triple GLP-1/GIP/glucagon agonist, sold as a research-use-only reagent. This page is an informational dosing reference and an honest pointer to what Titan actually carries.

How does tirzepatide dosing compare to retatrutide?

Both are dosed in single-digit-to-mid milligrams once weekly. Tirzepatide is a dual GIP/GLP-1 agonist titrated to a 15 mg ceiling; retatrutide adds a third receptor target (glucagon) and ran to 12 mg weekly in its Phase 2 obesity trial. The comparison pages break down how the receptor targets and dose ranges differ.

Tirzepatide · GIP/GLP-1 dual agonist · research use only

Tirzepatide dosage, laid out the way the trials titrate it.

Tirzepatide (LY3298176) is a dual agonist at the GIP and GLP-1 receptors, and its dosing is unusually well documented because the SURMOUNT and SURPASS programmes plus the FDA label published the exact escalation. This page reproduces the once-weekly 2.5→15 mg ladder, the four-week hold at each step, the ~5-day half-life behind the weekly cadence, and how a dual agonist differs from the triple agonist Titan actually stocks — framed as a research reference, not a human dosing protocol or medical advice. Titan does not sell tirzepatide; the compound Titan supplies in this class is retatrutide.

In-stock GLP-class: Retatrutide 10mg — $199.99 Reconstitution calculator

The 2.5 → 15 mg titration ladder

The label and trials start tirzepatide at 2.5 mg once weekly for four weeks — an initiation dose, not a maintenance target — then step up by 2.5 mg no sooner than every four weeks as tolerated: 5, 7.5, 10, 12.5 and a 15 mg ceiling. The slow ramp exists to manage the GI tolerability that defines the incretin class. Researchers modelling the compound follow the same staged escalation rather than jumping to the top dose.

Tirzepatide vs retatrutide →

~5-day half-life sets weekly dosing

Tirzepatide's elimination half-life is reported at roughly 5 days (about 120 hours) in the FDA clinical pharmacology review, which is what makes once-weekly the standard interval. A missed dose can be taken within about four days (96 hours); past that the schedule is reset. Practically, steady-state is approached over roughly four to five weeks — the same interval used to hold each titration step.

Compare half-lives →

Reconstitution math for research work

Research-grade tirzepatide ships lyophilized and the working concentration is set by the water you add. As a worked example, a 10 mg vial reconstituted with 1 mL of bacteriostatic water yields 10 mg/mL, so 0.25 mL on a U-100 insulin syringe draws 2.5 mg and 0.5 mL draws 5 mg; add 2 mL and every mark halves in strength. Always verify against the calculator before any in-vitro modelling.

Run the numbers →

Dual agonist vs triple agonist

Tirzepatide hits two receptors — GIP and GLP-1. Retatrutide, the compound Titan stocks, adds a third (glucagon), which is why it is described as a triple agonist and why its trial doses run to 12 mg weekly against tirzepatide's 15 mg. If a protocol is comparing incretin agents, the receptor count and the dose ceilings are the variables that actually separate them.

See the retatrutide vial →

Identity is the number that matters

A dosing model is only as good as the vial it is built on. For any incretin analog, confirm mass-spec identity and an HPLC main-peak purity result against a stated target — a mislabelled or under-purity lot makes the cleanest titration math meaningless. Titan documents identity and purity on a lot-matched release sheet for what it stocks; for out-of-catalog compounds, insist any vendor does the same.

How to read a COA →

Research-use framing

These figures describe the doses reported in human clinical trials and the FDA label, reproduced here as a research reference for in-vitro and laboratory modelling — not as instructions for human use. Tirzepatide is a prescription medicine; Titan does not sell it and supplies only research-use-only reagents, not for human or animal consumption. Nothing here is medical or dosing advice.

Research-use policy →

The detail, in plain terms

The dosing reference, in one table.

Tirzepatide's escalation is published in the FDA label and the SURMOUNT/SURPASS trials, which makes it a clean reference point. These are the variables a researcher weighs when modelling a titration — reproduced as a reference, not a human protocol. Titan stocks retatrutide, not tirzepatide.

Compound: Tirzepatide (LY3298176) — dual GIP / GLP-1 receptor agonist.
Trial / label doses: 2.5, 5, 7.5, 10, 12.5, 15 mg once weekly (subcutaneous).
Titration: Start 2.5 mg × 4 weeks, then +2.5 mg no sooner than every 4 weeks to a 15 mg ceiling.
Half-life: ≈5 days (~120 h) elimination — basis for the once-weekly cadence.
Titan catalog: Not stocked. In-class compound Titan sells: retatrutide 10mg, $199.99 (triple agonist).
Reconstitution: 10 mg vial + 1 mL BAC water → 10 mg/mL (0.25 mL = 2.5 mg); +2 mL → 5 mg/mL.

Questions researchers ask

Before you order.

What is the tirzepatide dosing schedule used in the research?: The trials and FDA label start tirzepatide at 2.5 mg once weekly for four weeks as an initiation dose, then escalate by 2.5 mg no sooner than every four weeks as tolerated through 5, 7.5, 10, 12.5 and a maximum of 15 mg weekly. These figures are reproduced as a laboratory research reference; they are not a human dosing protocol or medical advice.
What is tirzepatide's half-life?: The FDA clinical pharmacology review reports an elimination half-life of approximately 5 days (about 120 hours), which is why once-weekly administration is the standard interval and why steady-state is approached over roughly four to five weeks. A missed dose can generally be taken within about four days before the schedule resets.
Does Titan sell tirzepatide?: No. Titan does not stock tirzepatide, which is a prescription medicine. The compound Titan supplies in the same incretin class is retatrutide, a triple GLP-1/GIP/glucagon agonist, sold as a research-use-only reagent. This page is an informational dosing reference and an honest pointer to what Titan actually carries.
How does tirzepatide dosing compare to retatrutide?: Both are dosed in single-digit-to-mid milligrams once weekly. Tirzepatide is a dual GIP/GLP-1 agonist titrated to a 15 mg ceiling; retatrutide adds a third receptor target (glucagon) and ran to 12 mg weekly in its Phase 2 obesity trial. The comparison pages break down how the receptor targets and dose ranges differ.
Is tirzepatide approved for the uses discussed here?: Tirzepatide is an approved prescription medicine, but nothing on this page is a treatment recommendation. The dosing figures are reproduced strictly as a research reference for in-vitro and laboratory modelling. Titan supplies research-use-only reagents — not for human or animal consumption, diagnosis, treatment, or prevention — and nothing here is medical or dosing advice.