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Tirzepatide · Dosing

How Tirzepatide Is Actually Dosed

What does a real Tirzepatide (Mounjaro / Zepbound) dose schedule look like?

S-Tier Weight Loss FDA-approved

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The plain-English version

You start at 2.5mg once a week, then move up every four weeks until weight is coming off and side effects are tolerable. Most people land between 5mg and 15mg weekly. It is one shot a week, under the skin. Always with a doctor.

Route: subcutaneous injection. Evidence tier for the dose: FDA-approved. FDA-approved with multiple randomized trials behind it. The strongest evidence tier in this matrix.

The dose at a glance

What's typical What's the max in research
Starting dose: 2.5 mg subQ (under-the-skin shot) once weekly for the first 4 weeks. This is a starter dose - it is not meant to do real work, it is meant to wake your gut up gently. Max observed in research: 15 mg weekly is the FDA-approved max for both Zepbound (weight loss) and Mounjaro (diabetes), based on SURMOUNT-1 and SURPASS trial endpoints.
Maintenance dose: Most users settle between 5 mg and 15 mg weekly. Many plateau at 7.5 to 10 mg. Higher dose is not always better - the gut side effects scale with the dose.
Frequency: Once weekly. Same day every week. Pick a day and stick with it. Half-life: About 5 days. That is why once-weekly works - the drug is still in your system when the next dose lands.

Titration (how to ramp the dose)

Standard FDA titration ladder: 2.5 mg for 4 weeks -> 5 mg for 4 weeks -> 7.5 mg for 4 weeks -> 10 mg for 4 weeks -> 12.5 mg for 4 weeks -> 15 mg max. Most prescribers will hold you at whatever dose is working - if 7.5 mg is producing weight loss and tolerable side effects, do not push to 15 mg just because the ladder allows it.

Cycle length and time off

On cycle: Indefinite for chronic obesity or diabetes. Some users do 6 to 12 months for a defined weight-loss goal then taper.

Off cycle: If stopping, expect appetite and weight to drift back over 6 to 12 months without lifestyle changes. There is no required 'off cycle' for tirzepatide the way there is for some peptides.

Timing notes: Time of day does not matter. Most people inject morning of their chosen day to get gut side effects out of the way. Inject in stomach, thigh, or upper arm fat. Rotate sites week to week.

What's commonly prescribed (per published protocols and clinical write-ups)

Branded Mounjaro and Zepbound come as pre-filled single-use pens at fixed doses (2.5, 5, 7.5, 10, 12.5, 15 mg). Compounded tirzepatide from US pharmacies typically comes as a multi-dose vial in mg/mL concentration (often 10 mg/mL, sometimes 20 mg/mL) - you draw your own dose into a syringe. Telehealth (Hims, Henry Meds, Mochi, etc.) defaulted to compounded vials during the FDA shortage; many are transitioning back to brand or hybrid as the shortage ended.

Source: prescribing labels, published protocols, and clinical write-ups. We have not independently tested each prescriber pattern.

Reconstitution (mixing the vial)

Compounded tirzepatide ships pre-mixed in liquid form (no reconstitution needed) at a labeled concentration like 10 mg/mL. At 10 mg/mL, 0.5 mL on the syringe equals 5 mg. Store in fridge. Throw out at the expiration printed on the vial (usually 60-90 days from compounding).

Reconstitution = mixing freeze-dried (lyophilized) powder with bacteriostatic water (sterile water with preservative) so you can draw a dose into a syringe.

Drug interactions to watch

  • Slows gastric emptying, which delays absorption of oral medications - separate by at least 1 hour where possible.
  • Birth control pills: efficacy may be reduced for the first 4 weeks of titration and 4 weeks after dose increases. Use backup contraception.
  • Insulin and sulfonylureas: high hypoglycemia risk if combined - your prescriber should adjust those down.

Who should not take this (contraindications)

  • Personal or family history of medullary thyroid carcinoma (a rare thyroid cancer).
  • Multiple Endocrine Neoplasia syndrome type 2 (a rare genetic condition).
  • Active pancreatitis (inflamed pancreas).
  • Pregnancy and breastfeeding (stop at least 2 months before trying to conceive).

Common side effects

  • Nausea, especially in the first 2 weeks of each new dose (up to 30 percent of users).
  • Constipation or diarrhea.
  • Burping, reflux, that 'too full' feeling.
  • Fatigue in the first week.
  • Injection-site reaction (mild redness, itch).

Serious side effects (call a doctor)

  • Pancreatitis (severe persistent stomach pain that radiates to the back) - go to ER.
  • Gallbladder problems including stones (more common during rapid weight loss).
  • Severe dehydration from vomiting or diarrhea (especially in older users on diuretics).
  • Diabetic retinopathy worsening in pre-existing diabetics.
  • Allergic reaction including face swelling (rare but documented).

What to monitor while you're on it

  • Weight and waist measurement weekly for the first 12 weeks.
  • A1C and fasting glucose at baseline and every 3 months if diabetic.
  • Lipid panel and liver enzymes every 6 months.
  • Body composition scan (DEXA or InBody) at start and 6 months to confirm you are losing fat, not just lean mass.

How to stop

No formal taper required. You can stop anytime. Expect appetite to return over 4 to 8 weeks. To soften the rebound, drop one dose level for 4 weeks before quitting (e.g., 10 mg -> 7.5 mg -> 5 mg -> stop) and lock in lifestyle habits during that step-down.

Where this dosing comes from

  • SURMOUNT-1 trial (NEJM, 2022)
  • SURPASS-1 through SURPASS-5 trials (Lancet and NEJM, 2021-2022)
  • FDA prescribing information for Mounjaro and Zepbound
  • Compounded tirzepatide telehealth dosing protocols (Hims, Henry Meds, Mochi, Eden 2025)

Where these doses come from

These doses come from FDA-approved prescribing labels for Tirzepatide. The protocols are well-characterized in the SURMOUNT and SURPASS trials. Standard medical practice.

Always work with a real prescriber. Don't self-prescribe.

Safety reminder: None of this replaces a doctor. Peptides are gray-market in the US for most uses. Talk to a real prescriber before you change anything.

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Last reviewed · 2026-05-07 · Page generated by Protocol One matrix engine. None of this replaces a doctor. Peptides are gray-market in the US for most uses. Talk to a real prescriber before you change anything.