How much water do I add to Tirzepatide?

You can reconstitute Tirzepatide with 0.5, 1, or 2 mL of bacteriostatic water. Each option produces a different concentration and syringe draw for the same dose. Use the calculator to see which is easiest to measure.

What does Tirzepatide cost per dose?

Cost per dose depends on vial size, price paid, and your dose. Enter your vendor's price in the Tirzepatide calculator to see cost per dose and monthly cost.

What is the reference dose for Tirzepatide?

The commonly referenced range is 2.5 up to 15 mg per week (start low, increase slowly), taken weekly. This is reference information, not a recommendation. Talk to a licensed clinician.

What are the side effects of Tirzepatide?

Reported side effects of Tirzepatide include: Nausea, diarrhea, and vomiting are common, mostly early on and each time the dose increases.; Starting low and increasing slowly over several weeks keeps side effects milder.; It carries a warning about a rare thyroid tumor risk.. Severity and frequency vary by person and dose.

Who should not take Tirzepatide?

Tirzepatide is generally not appropriate for: A personal or family history of medullary thyroid cancer, or the genetic condition MEN 2; Pregnancy, or trying to become pregnant; A history of pancreatitis, which needs a conversation with your doctor first; Severe stomach-emptying problems (gastroparesis). Talk to a licensed clinician before starting.

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Decoding

Tirzepatide_

Q: What is Tirzepatide?

Tirzepatide is a glp-1 / gip agonist used for weight loss. Tirzepatide is a dual agonist that activates two gut-hormone receptors at once, GLP-1 and GIP. In plain terms: it works on two of your body's appetite-and-blood-sugar signals together, which tends to produce more weight loss than drugs that hit only one. It is the active drug in Mounjaro and Zepbound.

Q: Do you cycle Tirzepatide?

Not cycled Taken continuously. In SURMOUNT-4, people who kept taking it lost a further 5.5 percent over the following year while those switched to placebo gained 14 percent back. Stopping is the thing that undoes it.

Also known as Mounjaro, Zepbound, LY3298176

The drug in Mounjaro and Zepbound: a weekly shot for major weight loss and blood sugar.

Weight lossGLP-1 / GIP agonistFDA-approved

InGLP-1 agonists

Common vial size10 mg

Dose2.5 up to 15 mg per week (start low, increase slowly)

FrequencyWeekly

RouteUnder the skin (subcutaneous)

StatusFDA-approved

MixYour choice, calculate it

CycledNot cycled

Common vial size is what vendors typically sell, not a recommendation. Enter your own vial in the calculator.

What is Tirzepatide?

Plain language first. The technical label stays, but it never stands alone.

Overview

Tirzepatide is a dual agonist that activates two gut-hormone receptors at once, GLP-1 and GIP. In plain terms: it works on two of your body's appetite-and-blood-sugar signals together, which tends to produce more weight loss than drugs that hit only one. It is the active drug in Mounjaro and Zepbound.

What it's used for

People use it for major weight loss and better blood sugar. It works on two gut-hormone signals at once to reduce hunger, and tends to produce larger losses than older options.

How does Tirzepatide work?

What it does in the body, and where.

Tirzepatide is one molecule that fits two different receptors, GLP-1 and GIP. Adding the second target is what separates it from semaglutide.

01
It activates GLP-1, as semaglutide does
Slower stomach emptying, quieter appetite signalling, steadier blood sugar after meals.
02
It also activates GIP
A second gut hormone that appears to improve how well your body handles fat and sugar, and may soften the nausea from the GLP-1 side.
03
The two together do more than either alone
Trials have consistently produced larger weight loss than GLP-1 drugs on their own, at the cost of more gut side effects for some people.

Receptors

Hits 2 receptors at once.

What else is it used for?

Each group carries its own evidence level.

Approved means regulators have cleared it for that purpose. Investigational means it is in trials. Early research means it is being studied and is not established.

Weight loss

FDA-approved

Human trialIn a 72-week trial, average weight loss was 15.0% on 5 mg, 19.5% on 10 mg, and 20.9% on 15 mg, against about 3.1% on placebo.
Human trialAmong people who took it as directed, losses reached 16.0%, 21.4%, and 22.5%.
Human trial63% of people on the top dose lost at least a fifth of their body weight, and more than a third lost at least a quarter.
Human trialFat mass fell about three times more than lean mass, so most of what was lost was fat rather than muscle.

Study

SURMOUNT-1 results, Eli Lilly / NEJM, 2022

Diabetes and blood sugar

FDA-approved

Human trial95% of people who had prediabetes returned to normal blood sugar across the doses.
RegulatoryApproved as Mounjaro in 2022 for type 2 diabetes and as Zepbound in 2023 for obesity.

Study

SURMOUNT-1 results, Eli Lilly / NEJM, 2022

How much, and do you cycle it?

The range, and whether you take breaks.

2.5 up to 15 mg per week (start low, increase slowly), weekly. Not cycledHuman study

Taken continuously. In SURMOUNT-4, people who kept taking it lost a further 5.5 percent over the following year while those switched to placebo gained 14 percent back. Stopping is the thing that undoes it.

Source: Aronne et al., SURMOUNT-4: tirzepatide withdrawal (JAMA 2024)

Compare cycling across compounds →

How do I dose and price it?

Enter your vial and your dose. Pick a mix. We show the draw and the cost.

The vial holds a fixed amount of drug. Adding more water does not make more drug, it just spreads it thinner, so you draw a bigger number on the syringe for the same dose.

Your vial size (mg)

Printed on the vial.

What you paid per vial

Used for cost per dose only.

Your dose (mg)

Commonly referenced range: 2.5 up to 15 mg per week (start low, increase slowly)FDA label

Choose your mix

0.5 mL water13units · 20 mg/mL

Half a 100-unit syringe

1 mL water25units · 10 mg/mL

One full 100-unit syringe

Easiest

2 mL water50units · 5 mg/mL

Two full 100-unit syringes

your own mL

units · —

Enter your own volume

Measuring the water1 mL = one full 100-unit syringe.

Your draw

50 / 100 units

Full calculator with reorder date →Read a syringe →

How do you store it?

Before mixing, and after.

Fridge before first use. Room temperature is fine once in use.

Sealed pens live in the fridge. Once you start a pen it can stay at room temperature for the in-use window on the label (often about 4 to 6 weeks depending on the product). Keep it out of light, do not freeze it, and toss it if it has been frozen or left hot.

What are the side effects and cautions?

Known cautions and warnings for this compound.

22 July 2026In January 2026 the FDA asked that the warning about suicidal thoughts and behaviour be removed from the obesity versions of this drug family after a review found no increased risk. Labels were updated in February 2026.

Who should avoid it

Check these before anything else.

A personal or family history of medullary thyroid cancer, or the genetic condition MEN 2
Pregnancy, or trying to become pregnant
A history of pancreatitis, which needs a conversation with your doctor first
Severe stomach-emptying problems (gastroparesis)

Stop and get help

These are emergencies. Seek care.

Severe stomach pain that spreads to your back
A lump or swelling in your neck, hoarseness, or trouble swallowing
Vomiting badly enough that you cannot keep fluids down
Sudden changes in your vision
Signs of an allergic reaction such as face or throat swelling or trouble breathing

Common effects

Expected, and usually mild.

Nausea, worst in the first weeks and after each dose increase
Diarrhea, constipation, and vomiting
Tiredness
Reduced appetite to the point of forgetting to eat
Injection-site redness

Where this page says nothing is established, that means nobody has studied it, not that a compound is safe.

Is Tirzepatide approved?

And where the numbers on this page come from.

FDA-approved

Yes. FDA-approved.

In January 2026 the FDA asked that the warning about suicidal thoughts and behaviour be removed from the obesity versions of this drug family after a review found no increased risk. Labels were updated in February 2026.

DoseFrom the drug label. The manufacturer tested this range and a regulator reviewed it.
Vial sizeFrom what vendors typically list; not a recommendation.
Sources
American Academy of Sleep Medicine, FDA approval for sleep apnea Eli Lilly, SURMOUNT-OSA sleep apnea results FDA, removal of the suicidal-ideation warning (Jan 2026)SURMOUNT-1 results, Eli Lilly / NEJM, 2022
Reviewed22 July 2026

What else is like Tirzepatide?

Others in Weight loss and metabolic, side by side.

If you're weighing Tirzepatide, it's worth reading Semaglutide, Retatrutide, and Cagrilintide in the same class.

YOU ARE HERE

Tirzepatide

The drug in Mounjaro and Zepbound: a weekly shot for major weight loss and blood sugar.

FDA-approved

Dose: 2.5 up to 15 mg per week (start low, increase slowly)
How often: Weekly

Semaglutide

The drug in Ozempic and Wegovy: a weekly shot that curbs hunger for steady weight loss.

FDA-approved

Dose: 0.25 up to 2.4 mg per week (start low, increase slowly)
How often: Weekly

Retatrutide

An experimental weekly shot with some of the biggest weight-loss numbers yet in trials.

Investigational

Dose: 1 up to 12 mg per dose (start low, increase slowly)
How often: Weekly

CAGRI

Cagrilintide

A weekly fullness-hormone shot, often paired with semaglutide for bigger loss.

Investigational

Dose: 0.3 up to 4.5 mg per dose (start low, increase slowly)
How often: Weekly

How Tirzepatide compares to other GLP-1 peptides

Side by side with every GLP-1 agonist

What these words mean

Show glossary +

Titrate: Starting at a low dose and increasing it slowly over time so your body adjusts and side effects stay mild.
Subcutaneous: An injection just under the skin, into the fat layer, usually with a short, thin insulin needle.
Intramuscular (IM): An injection into a muscle, using a longer needle.
Reconstitution: Mixing a powdered peptide with liquid (bacteriostatic water) so it can be drawn into a syringe.
Bacteriostatic water: Sterile water with a tiny amount of preservative, used to mix powdered peptides.
Concentration: How strong the mixed peptide is, in milligrams per milliliter (mg/mL). More water makes it weaker; less water makes it stronger.
Units (on the syringe): The marks on an insulin syringe. 100 units equals 1 mL. They measure how much liquid you draw, not the dose in milligrams.
mcg and mg: Units of dose. 1 milligram (mg) equals 1,000 micrograms (mcg).
GLP-1: A natural gut hormone that lowers appetite and blood sugar. Drugs that copy it, like semaglutide, are used for weight loss.
Growth hormone secretagogue: A compound that nudges your body to release more of its own growth hormone, rather than injecting the hormone itself.
Half-life: How long a compound stays active in your body. A longer half-life means you inject less often.
Peptide vs small molecule: A peptide is a short chain of amino acids. A few items here (like MK-677 or methylene blue) are small molecules, not true peptides, but people use them the same way.
Research only: No approved dose or use in people. Sold for research and not reviewed by the FDA for safety or quality.
Investigational: Still being tested in clinical trials and not yet approved or legally sold for general use.
Banned in drug-tested sport: Prohibited by the World Anti-Doping Agency (WADA); using it can disqualify a competing athlete.

Sources

American Academy of Sleep Medicine, FDA approval for sleep apnea(2024)
First approval of a drug in this family for obstructive sleep apnea.
Eli Lilly, SURMOUNT-OSA sleep apnea results(2024)
SURMOUNT-OSA trial, with up to 51.5% of participants meeting criteria for disease resolution.
FDA, removal of the suicidal-ideation warning (Jan 2026)(2026)
FDA asked for the suicidal-ideation warning to be removed after a review found no increased risk.
SURMOUNT-1 results, Eli Lilly / NEJM, 2022

Last reviewed 22 July 2026