Microdosing tirzepatide: doses, cost and evidence

What counts as a microdose

There is no agreed definition. The term is used by telehealth companies and online communities, not by the FDA label. The label's doses are 2.5, 5, 7.5, 10, 12.5 and 15 mg once weekly. It uses 2.5 mg only for the first 4 weeks and lists 5, 10 and 15 mg as maintenance doses for weight ^[1]. Anything under 2.5 mg, or staying long term on 2.5 mg, is outside the label.

So is 5 mg a low dose? It is the lowest labeled maintenance dose ^[1], and in SURMOUNT-1 it produced an average loss of 15.0% at 72 weeks ^[2]. It is not a microdose in any labeled sense.

What the evidence shows

The trials behind Zepbound tested 5, 10 and 15 mg ^[4]. We found no trial of doses lower than the label's, so there is no trial answer to whether microdosing causes weight loss, keeps weight off, or eases inflammation. Inflammation is not an approved use of tirzepatide ^[1].

The labeled doses also do not show that lower always means gentler. Nausea was 25% on 5 mg, 29% on 10 mg and 28% on 15 mg, and constipation was actually highest on 5 mg, at 17% vs 14% and 11% ^[4]. The label slows dose increases to every 4 weeks or more, and in SURMOUNT-1 stomach side effects came mainly during escalation ^{[1] [2]}. That is the label's approach to tolerability.

For keeping weight off, the best data are from SURMOUNT-4. It compared continuing tirzepatide with switching to placebo, not with a reduced dose. People who stopped regained 14.0% over a year, while those who continued lost a further 5.5% ^[5]. No trial in our research tested stepping down to a microdose. See stopping tirzepatide.

Is it safe?

There are no safety data for doses lower than the label's. The label's warnings, including the boxed warning about thyroid C-cell tumors in rats and the risks of pancreatitis and gallbladder disease, apply to tirzepatide at any dose ^[4]. Most microdose plans use compounded tirzepatide, which is not FDA-approved and is not reviewed by FDA for safety, effectiveness or quality ^[3]. FDA had received more than 730 adverse event reports for compounded tirzepatide by May 31, 2026 ^[3]. Full list on tirzepatide side effects.

How microdosing is done, and why we give no instructions

Small doses usually come from compounded multi-dose vials measured with a syringe. The amount of tirzepatide in a given number of syringe units depends on the concentration printed on the pharmacy label, so follow your prescriber's instructions and that label exactly, and ask your pharmacist to confirm the dose. We do not publish microdose schedules, unit counts or mixing steps. FDA has received reports of harm, some needing hospital care, from people mismeasuring compounded injectable semaglutide and from clinicians miscalculating doses ^[3].

Brand pens are not built for it. Zepbound and Mounjaro pens and vials hold set doses of 2.5 to 15 mg ^[1], and the label gives no way to take part of a dose. Mounjaro is approved for type 2 diabetes, and its label starts at 2.5 mg too ^[6]. The labels are written for once-weekly dosing, with doses at least 72 hours apart if you change your day ^[1]; twice-weekly microdosing is not part of them.

Who sells microdose plans, and what they cost

Seen on October 17, 2026:

• bmiMD lists a compounded tirzepatide microdose alongside its regular compounded tirzepatide, which it advertises as low as $179 a month (plan length not shown) ^[8]. bmiMD review.
• Found lists a microdosing program; its compounded tirzepatide plans run $239 to $359 per 28 days in cash depending on plan length, with labs extra ^[9]. Found review.
• Noom sells a "microdose GLP-1" program: $99 plus tax for a 3-week subscription with 4 weeks of medication, then $199 a month plus tax on a 12-week subscription ^[10]. Its footnotes reference compounded drugs. Noom Med review.

For scale, labeled Zepbound at 2.5 mg costs $299 a month on LillyDirect ^[11]. Watch for plan lock-ins, membership fees and lab costs on top of the drug price. Full comparisons are on tirzepatide cost and compounded tirzepatide. The semaglutide version of this question is on microdosing semaglutide.

Questions to ask before you start

1. What dose in mg will I take, and why that dose rather than a labeled one?
2. Which pharmacy makes it, and what concentration is on its label?
3. What evidence supports this dose for my goal?
4. How will side effects be checked, and who do I call?
5. What is the total monthly cost, and how long is the plan commitment?