Sources — estimated medication level
Estimated from logged doses — not a measured blood level.
The curve is computed from the doses the patient logged and from published pharmacokinetic parameters for the compound they are taking — half-life, time to peak, volume of distribution and, where it has been measured, subcutaneous bioavailability. It is the same model, with the same inputs, that the patient sees in their own app. It is not a blood test, it has never been validated against one for any individual, and nothing on this page is a dosing recommendation.
Where each number comes from
Manufacturers' prescribing information for the dose ladders and label windows; peer-reviewed pharmacokinetics for the half-lives and absorption parameters. Every link opens the publisher's own document.
- Ozempic (semaglutide) — US Prescribing Information & Instructions for Use
Novo Nordisk · 2025
The approved injection areas (abdomen, thigh, upper arm), the instruction to change site with each dose, the 0.25 to 2 mg ladder, and semaglutide's ~1-week half-life. Its Adverse Reactions section is also what Tiro's what-to-expect list rests on.
- Wegovy (semaglutide) — US Prescribing Information & Instructions for Use
Novo Nordisk · 2025
The approved injection areas, the site-rotation instruction, and the 0.25 to 2.4 mg monthly escalation schedule. Its Adverse Reactions section backs the effects Tiro says to expect at each step.
- Mounjaro (tirzepatide) — Instructions for Use
Eli Lilly and Company · 2025
Rotating the site within an area to reduce the risk of lipodystrophy, avoiding tender/bruised/scarred/lumpy skin, and the 2.5 to 15 mg 4-weekly steps. Its Adverse Reactions section backs the effects Tiro says to expect on tirzepatide.
- Zepbound (tirzepatide) — US Prescribing Information
Eli Lilly and Company · 2025
The 2.5 to 15 mg dose ladder Tiro offers for Zepbound, its 4-week steps, and — from its Adverse Reactions section — the effects Tiro says to expect at each step.
- Trulicity (dulaglutide) — US Prescribing Information
Eli Lilly and Company · 2025
The 0.75 to 4.5 mg ladder, and dulaglutide's half-life, time-to-peak and bioavailability used in the level curve.
- Saxenda (liraglutide) — US Prescribing Information
Novo Nordisk · 2025
The 0.6 to 3.0 mg weekly-step ladder, and liraglutide's ~13-hour half-life used in the level curve.
- Victoza (liraglutide) — US Prescribing Information
Novo Nordisk · 2025
The 0.6 to 1.8 mg ladder Tiro offers for Victoza.
- Rybelsus (semaglutide tablets) — US Prescribing Information
Novo Nordisk · 2025
The 3 to 14 mg oral ladder, and that oral and injected doses are not interchangeable.
- Triple-Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial
Jastreboff et al., New England Journal of Medicine — via PubMed · 2023
That retatrutide is INVESTIGATIONAL — not an approved medicine anywhere, with trial data all that exists. Tiro plans no dose schedule for it and only records what you enter.
- TRIUMPH-1 phase 3 topline results — retatrutide in obesity
Eli Lilly and Company (investor release) · 2026
The 2 / 4 / 6 / 9 / 12 mg once-weekly strengths Tiro lists for retatrutide, which are the phase 3 trial dose levels. These are trial doses, not approved doses — no regulator has licensed retatrutide.
- LY3437943, a novel triple GIP/GLP-1/glucagon receptor agonist — first-in-human study
Coskun et al., Cell Metabolism — via PubMed · 2022
The half-life (~6 days), time-to-peak and volume of distribution Tiro uses to estimate retatrutide levels. No absolute bioavailability has ever been measured for it, so that one input is an assumption and the curve is an estimate, not a measurement.
- Clinical Pharmacokinetics of Semaglutide: A Systematic Review
Yang & Yang, Drug Design, Development and Therapy — via PubMed · 2024
Half-life, time-to-peak and subcutaneous bioavailability behind the semaglutide level curve.
- Clinical Pharmacokinetics of Oral Semaglutide: Analyses of Data from Clinical Pharmacology Trials
Overgaard et al., Clinical Pharmacokinetics — via PubMed · 2021
Why Tiro shows a tablet dose so differently from an injection: oral semaglutide's bioavailability is around 0.8%, against roughly 89% injected.
- Population pharmacokinetics of tirzepatide
Schneck et al., CPT: Pharmacometrics & Systems Pharmacology — via PubMed · 2024
Half-life and absorption parameters behind the tirzepatide level curve.
Each URL was verified to resolve on 28 July 2026. Where a paper sits behind a publisher’s paywall it is cited by its PubMed record instead, which is free and stable. If a link here has since moved, the record it supports is unchanged — tell us and we will re-point it.