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Tirzepatide

Approved weight-loss, diabetes, sleep-apnea drug

The drug in Mounjaro and Zepbound

Match every finding to its exact substance, formulation, route and study population. A related molecule or approved medicine does not validate a catalog vial.

Human / product-specific records
Schematic illustration · View structure evidence

Simplified drawing of a chain of 39 amino acids, with its fatty-acid tail

At a glance

Why people take it. And what backs it up.

  1. Lose weight

    Approved for obesity (Zepbound)

    Approved as Zepbound for adults with obesity, or overweight plus a related illness; on the top dose adults lost about 21%, more than semaglutide.

    Sources (3)
  2. Control type 2 diabetes

    Approved for type 2 diabetes (Mounjaro)

    Prescribed as Mounjaro to lower blood sugar in adults and children 10 and older with type 2 diabetes, alongside diet and exercise.

    Sources (2)
  3. Ease sleep apnea

    Approved for sleep apnea with obesity

    Approved as Zepbound for adults with obesity and moderate to severe sleep apnea; in trials, breathing pauses during sleep fell by up to 59%.

    Sources (2)
  4. Microdose for inflammation and cravings

    People report it, not studied

    Many take tiny doses, well below the 2.5 mg starting dose, to calm inflammation or quiet food cravings rather than to lose much weight.

    Sources (3)
  5. Keep weight off

    Early human studies

    After reaching goal, many stretch doses weeks apart or drop to a low dose to hold their weight for less money.

    Sources (4)

Evidence briefing

Sources checked

What the sources support.

Tirzepatide is FDA-approved as Mounjaro for type 2 diabetes and Zepbound for chronic weight management and obesity-related sleep apnea; 2026 Mounjaro labeling adds cardiovascular risk reduction for a defined high-risk type 2 diabetes population. Research-vial products are not the approved products.

Keep in mind

Approval does not establish the identity, purity or equivalence of research-vial products.

Identity and research status reviewRead the original sources

The research. What’s been studied.

TapClick a dotted word to see what it means.

  • Human evidence

    Greater weight loss

    About 21% average weight loss at the top dose over 72 weeks, and more than semaglutide in a head-to-head trial.

  • Human evidence

    Blood sugar control

    Produced some of the largest A1c reductions seen in type 2 diabetes trials.

  • Human evidence

    Sleep apnea improvement

    FDA-approved for obstructive sleep apnea with obesity; it cut breathing interruptions during sleep substantially.

  • Human evidence

    Appetite control

    Reduces hunger and portion sizes through two gut-hormone pathways ( and GIP).

  • Early human studies

    Better metabolic markers

    Trials also showed lower blood pressure, triglycerides and liver fat.

What do these labels mean?
  • Human evidence: approved-drug data or larger human studies, within the populations and uses studied.
  • Early human studies: small, preliminary or limited human studies.
  • Animal & lab studies: animal or laboratory findings that do not establish effects in people.
  • Unverified: a proposed use or claim without verified supporting clinical evidence.
How each claim was reviewed (5)

Reported effects and evidence.

A citation may support, qualify or correct a claim. Read the study scope; a laboratory result is not an established benefit in people. Each review covers a claim as it was first collected; the tiles above show the collection’s current wording.

  1. Human RCT; two separate trials

    Review of “Greater weight loss”

    SURMOUNT-1 reported 20.9% mean loss at its highest studied dose over 72 weeks. SURMOUNT-5 separately favored tirzepatide over semaglutide.

    Limitations and applicability. Separate SURMOUNT-1 from head-to-head SURMOUNT-5; do not imply indirect cross-trial comparison.

    Original collected claim and review history

    Original title: Greater weight loss

    About 21% average weight loss at the top dose over 72 weeks, and more than semaglutide in a head-to-head trial.

    Original headline statistic: About 21%

    Original label: proven. Preserved for traceability; the reviewed wording above qualifies this record.

    Record tirzepatide:benefit:1 · Annotated 2026-10-01 · Review method

  2. Human RCT / approved diabetes indication

    Review of “Blood sugar control”

    In SURPASS-2, tirzepatide reduced HbA1c more than the semaglutide comparator in adults with type 2 diabetes.

    Limitations and applicability. “Some of the largest” is an undefined ranking. Provide trial-specific effect rather than superlative.

    Original collected claim and review history

    Original title: Blood sugar control

    Produced some of the largest A1c reductions seen in type 2 diabetes trials.

    Original label: proven. Preserved for traceability; the reviewed wording above qualifies this record.

    Record tirzepatide:benefit:2 · Annotated 2026-10-01 · Review method

  3. Approved indication; human phase 3 RCT

    Review of “Sleep apnea improvement”

    Zepbound is approved for moderate-to-severe obstructive sleep apnea in adults with obesity; trials reduced apnea–hypopnea events.

    Limitations and applicability. Approval is for moderate-to-severe OSA in adults with obesity, using the approved product.

    Original collected claim and review history

    Original title: Sleep apnea improvement

    FDA-approved for obstructive sleep apnea with obesity; it cut breathing interruptions during sleep substantially.

    Original label: proven. Preserved for traceability; the reviewed wording above qualifies this record.

    Record tirzepatide:benefit:3 · Annotated 2026-10-01 · Review method

  4. Approved-product pharmacology

    Review of “Appetite control”

    Tirzepatide activates GIP and GLP-1 receptors and reduces caloric intake through effects on appetite.

    Limitations and applicability. Mechanistic description is reasonable; distinguish receptor activity from separately proven contribution of each pathway.

    Original collected claim and review history

    Original title: Appetite control

    Reduces hunger and portion sizes through two gut-hormone pathways (GLP-1 and GIP).

    Original label: proven. Preserved for traceability; the reviewed wording above qualifies this record.

    Record tirzepatide:benefit:4 · Annotated 2026-10-01 · Review method

  5. Human trial secondary outcomes; bundled claim

    Review of “Better metabolic markers”

    Trials reported improvements in selected cardiometabolic measures. Present blood pressure, triglyceride and liver-fat findings as separate endpoints.

    Limitations and applicability. Blood pressure/lipids have trial evidence. This citation does not verify the liver-fat component; split and source separately.

    Original collected claim and review history

    Original title: Better metabolic markers

    Trials also showed lower blood pressure, triglycerides and liver fat.

    Original label: early. Preserved for traceability; the reviewed wording above qualifies this record.

    Record tirzepatide:benefit:5 · Annotated 2026-10-01 · Review method

The research in detail

Evidence category

FDA-approved (US)

In SURMOUNT-1, adults with obesity lost about 21% of body weight on the highest dose over 72 weeks. In a head-to-head trial (SURMOUNT-5) it produced more weight loss than semaglutide.

Evidence is assessed claim by claim above. Regulatory approval, study design, findings and relevance are separate questions; there is no single evidence score.

Risks and unknowns. What to know first.

Collected cautions follow. These are not an exhaustive or independently validated safety assessment; claim references do not automatically support every caution.

  • Similar to semaglutide: GI upset, possible gallbladder disease and pancreatitis, and the rodent thyroid-tumor warning.
  • Can reduce the reliability of birth-control pills around dose changes.

What people report

Show all 6 cautionsShow fewer cautions

Read this first: what “research use only” means

Published dosing records. What the approved label says.

Historical label and trial records for the named product, route, population and indication. These records are not a personal schedule or a validated regimen for a catalog vial. Source attribution does not establish applicability.

Zepbound

Long-term weight management in adults with obesity, or with overweight and a weight-related health problem. Also moderate to severe obstructive sleep apnea in adults with obesity.

Long-termApproved label

Source: Zepbound prescribing information (FDA, revised 08/2026) (opens in a new tab)

How
Injection under the skin (belly or thigh; back of the upper arm if someone else gives it)
How often
Once a week
How long
Ongoing

Dose, step by step

  1. Weeks 1–4 2.5 mg
  2. Weeks 5–8Can stay on 5 mg
  3. Weeks 9–12 7.5 mg (only if needed)
  4. Weeks 13–16Can stay on 10 mg (only if needed)
  5. Weeks 17–20 12.5 mg (only if needed)
  6. Week 21 onCan stay on 15 mg (only if needed)

Limit. 15 mg once a week.

  • Each step lasts at least 4 weeks; the weeks shown are the fastest the label allows. For weight loss, going past 5 mg is optional: the stay-on doses are 5, 10 or 15 mg. For sleep apnea, the stay-on doses are 10 or 15 mg, so the dose must rise to at least 10 mg.
  • If a maintenance dose is not tolerated, the label says to consider a lower one.
  • Missed dose: given within 4 days (96 hours); after that it is skipped. The weekly day can be changed if doses stay at least 3 days (72 hours) apart.

Mounjaro

Type 2 diabetes (blood sugar control) in adults and in children 10 and older. Also lowers heart risk in adults with type 2 diabetes who are at high risk.

Long-termApproved label

Source: Mounjaro prescribing information (FDA, revised 08/2026) (opens in a new tab)

How
Injection under the skin (belly or thigh; back of the upper arm if someone else gives it)
How often
Once a week
How long
Ongoing

Dose, step by step

  1. Weeks 1–4 2.5 mg
  2. Weeks 5–8 5 mg (only if needed)
  3. Weeks 9–12 7.5 mg (only if needed)
  4. Weeks 13–16 10 mg (only if needed)
  5. Weeks 17–20 12.5 mg (only if needed)
  6. Week 21 on 15 mg (only if needed)

Limit. 15 mg once a week for adults; 10 mg once a week for children.

  • Each increase is only for when more blood sugar control is needed, after at least 4 weeks on the current dose; people stay on the dose that works. The weeks shown are the fastest the label allows. Children stop at 10 mg.
  • Missed dose: given within 4 days (96 hours); after that it is skipped.

These are the label’s doses for the approved medicine, started and adjusted by a prescriber. A research vial is not that medicine: no regulator has checked what’s in it, or how much.

Community protocols. Reported online. Not clinically validated.

Community reports Collection date: 30 Sep 2026

Grey-market users mostly copy the label ladder (2.5 mg, rising 2.5 mg at a time) using research vials measured in syringe units, but often climb more slowly. Microdosing below 2.5 mg (about 0.15–2 mg a week) has become a mainstream telehealth and forum trend, and splitting the weekly dose or stretching the gap between doses is also common.

Not testedFrequently encountered in reviewed sources

Grey-market vials following the label ladder

Collected report · exact form and route are only as reported below. Source date and reporter identity are not separately verified. Collection checked 30 Sep 2026; presentation annotated 2026-10-01.

Frequency labels describe this collection, not a measured population. Contradictory records remain available.

Details and sourcesHide details
Dose
2.5 mg, then up in 2.5 mg steps (to 15 mg at most)
How often
Once a week (every 7 days)
Route
Injection under the skin (belly, thigh or upper arm)
Timing
Same day each week
How long
Open-ended
Ramp
Every 4 weeks on paper, but many move up far more slowly, sometimes every 2 months or more
Mixing
For example 60 mg vial + 3 mL bacteriostatic water (20 mg/mL, so 10 mg = 50 units); “1 mL for every 10 mg” is a common rule. Vials come in 10-vial “kits” (for example 10 × 30 mg).
  • Buyers are urged to have each batch lab-tested for identity, purity and fill.
  • Many users with compounded pharmacy vials follow the same ladder converted to syringe units.
Sources (4)

Not testedCommon

Microdosing (below 2.5 mg)

Collected report · exact form and route are only as reported below. Source date and reporter identity are not separately verified. Collection checked 30 Sep 2026; presentation annotated 2026-10-01.

Frequency labels describe this collection, not a measured population. Contradictory records remain available.

Details and sourcesHide details
Dose
About 0.15–2 mg (telehealth programs commonly 1–2 mg; some start at 0.15 mg)
How often
Once a week
Route
Injection under the skin
How long
Open-ended
Ramp
Often small weekly steps (one provider: 0.15 mg, then up 0.05 mg a week)
Mixing
Drawn as a few units from a 2.5 mg/0.5 mL vial, or set by counting clicks on a 2.5 mg KwikPen (10 clicks ≈ 0.43 mg in one user’s account)
  • Used for binge-eating control, swelling (lipedema), inflammation, or to avoid side effects, not only for weight loss.
  • The originator of GLP-1 “microdosing” says 2.5 mg is a standard dose, not a microdose.
Sources (4)
Show all 4 protocolsShow fewer protocols

Not testedCommon

Split dosing

Collected report · exact form and route are only as reported below. Source date and reporter identity are not separately verified. Collection checked 30 Sep 2026; presentation annotated 2026-10-01.

Frequency labels describe this collection, not a measured population. Contradictory records remain available.

Details and sourcesHide details
Dose
Same weekly total, divided (for example 5 mg as 2 × 2.5 mg)
How often
Twice a week, or every 3–6 days
Route
Injection under the skin
Timing
For example Monday and Thursday
  • Done to smooth out side effects and hunger late in the week. Common among grey-market users because vials make any dose possible.
Sources (3)

Not testedCommon

Stretching the interval for maintenance

Collected report · exact form and route are only as reported below. Source date and reporter identity are not separately verified. Collection checked 30 Sep 2026; presentation annotated 2026-10-01.

Frequency labels describe this collection, not a measured population. Contradictory records remain available.

Details and sourcesHide details
Dose
Usually 2.5 mg, or a partial pen dose
How often
Every 2 weeks up to about once a month, or only when hunger returns
Route
Injection under the skin
How long
Long-term maintenance
  • Used after reaching goal weight to cut cost and side effects. Some also take smaller doses from higher-strength pens to make a pen last longer.
Sources (4)

Where the numbers come from

Grey-market practice copies the label’s 2.5 mg ladder, spread through community guides such as Stairway to Gray and subreddit wikis. Microdosing grew from telehealth practice and influencer promotion. A September 2026 telehealth preprint describes patients started at 1–2 mg a week, but no trial has tested these doses.

Research notes

“Microdose” is used loosely: telehealth programs call 1–2 mg a microdose, forum users go down to 0.04–0.16 mg, and the idea’s originator says any standard starting dose is not a microdose. Grey-market vial strength and purity are unverified unless tested.

What it is. In plain English.

A dual-hormone drug that produces more weight loss than GLP-1 alone.

A 39-amino-acid peptide built on the GIP hormone backbone and engineered to also hit the GLP-1 receptor, with a fatty-acid chain for once-weekly dosing. Sold here under the code NXP-2P (two receptor targets).

It activates two gut-hormone receptors, GIP and GLP-1. The GLP-1 side curbs appetite and slows digestion; the GIP side appears to improve insulin response and may soften nausea.

Reviewed 2026-10-01.

Structure. What it really looks like.

Experimental

Cryo-EM structure of tirzepatide (teal) bound to the human GLP-1 receptor (gray).

Tirzepatide (teal) bound to the human GLP-1 receptor (gray), one of the two receptors it acts on. Also part of the experiment, but not drawn: a G protein and two antibody fragments.

Missing parts

  • The fatty-acid side chain isn’t in this model.
  • The last eight of the peptide’s 39 amino acids have no coordinates.

7RGP, Sun et al., 2022. Rendered with Mol* (Sehnal et al., 2021) from RCSB PDB data (Berman et al., 2000).

ExperimentalCryo-EM3.08 Å

Cryo-EM structure of tirzepatide (teal) bound to the human GIP receptor (gray).

Tirzepatide (teal) bound to the human GIP receptor (gray), the other receptor it acts on. Also part of the experiment, but not drawn: a G protein, two antibody fragments and a small molecule bound inside the receptor.

Missing parts

  • The fatty-acid side chain isn’t in this model.
  • The last seven of the peptide’s 39 amino acids have no coordinates.

PDB 7RBT, Sun et al., 2022. Rendered with Mol* (Sehnal et al., 2021) from RCSB PDB data (Berman et al., 2000).

Specs. The facts at a glance.

Length
39 amino acids + fatty-acid chain
Sold as
  • NXP-2P kit · 10, 15, 20, 30 or 60 mg
Regulatory status
FDA-approved in the US as Mounjaro for type 2 diabetes, including pediatric patients 10 and older, and for reducing major cardiovascular events in adults with type 2 diabetes at high cardiovascular risk; and as Zepbound for chronic weight management and moderate-to-severe obstructive sleep apnea in adults with obesity. Approval applies to the labeled products, not research-vial tirzepatide.
Also known as
The drug in Mounjaro and Zepbound

Sources. What this page rests on.

Every source behind this page, with what it says and when it was checked, is in the Source library.

Tirzepatide in the Source library

Original overview and research notes · annotated 2026-10-01

Historical collection text. Read alongside the claim corrections above; identity or evidence qualifications may supersede this wording.

Weight loss and blood sugar control

A dual-hormone drug that produces more weight loss than GLP-1 alone.

A 39-amino-acid peptide built on the GIP hormone backbone and engineered to also hit the GLP-1 receptor, with a fatty-acid chain for once-weekly dosing. Sold here under the code NXP-2P (two receptor targets).

It activates two gut-hormone receptors, GIP and GLP-1. The GLP-1 side curbs appetite and slows digestion; the GIP side appears to improve insulin response and may soften nausea.

In SURMOUNT-1, adults with obesity lost about 21% of body weight on the highest dose over 72 weeks. In a head-to-head trial (SURMOUNT-5) it produced more weight loss than semaglutide.

Original status record: FDA-approved as Mounjaro (type 2 diabetes, 2022; reducing heart attack and stroke risk in type 2 diabetes, 2026) and Zepbound (obesity, 2023; obstructive sleep apnea, 2024).

More in Weight & metabolism.

Glossary

GLP-1 / GIP

Gut hormones released after eating that raise insulin and reduce appetite. The basis of today’s weight-loss drugs.

Glossary

Cryo-EM

Cryo-electron microscopy. Molecules are frozen in a thin layer of ice and photographed thousands of times with an electron microscope; the images are combined into a 3D map.

Glossary

Resolution

How sharp a structure is, measured in ångströms (Å; a ten-billionth of a meter). Smaller is sharper.

Glossary

Protein Data Bank (PDB)

The free worldwide archive of 3D structures of proteins and other molecules measured in experiments. Each entry has a four-character code, like 7KI0.