What “microdosing” actually means
Microdosing a GLP-1 means using a dose lower than the drug’s standard starting dose — and since those starting doses are already the lowest ones the label describes, a microdose is by definition off-label. The chart above shows what illustrative low-dose ranges look like for semaglutide and tirzepatide, so you can see how far below “normal” a microdose sits.
It helps to anchor on the real numbers. The FDA-label starting doses — semaglutide 0.25 mg and tirzepatide 2.5 mg — are already deliberately low, chosen to build tolerance rather than to produce results. Microdosing goes below even those. That’s why the single most common question, “is 2.5 mg of tirzepatide a microdose?”, has a clear answer: no — 2.5 mg is the standard first step everyone starts on.
Why people do it
There’s no approved use for microdosing, but the reasons people try it are consistent:
- To minimize side effects. Some people are extremely sensitive to the nausea and GI effects and find even the starting dose hard. A slower, lower on-ramp can help them stay on the drug.
- To maintain results on less. After reaching a goal weight, some want the smallest dose that holds their appetite in check rather than staying at a full maintenance dose.
- To stretch supply. When the drugs are expensive or hard to get, lower doses last longer — though this is the shakiest rationale medically.
What the evidence says
Here’s the honest part: the evidence for microdosing is thin. The pivotal trials studied the standard titration schedules, not sub-starting doses, so we don’t have good data on how much weight loss or metabolic benefit a true microdose delivers. It’s plausible that lower doses do proportionally less — appetite suppression is dose-related — but “plausible” isn’t “proven.” Anyone telling you a specific microdose schedule is optimal is going beyond what the research supports.
If you’re considering it
Microdosing lives entirely in off-label territory, which means the tested guardrails don’t apply and a clinician’s judgment matters more, not less. The illustrative ranges in the chart are there to show what “below the starting dose” looks like — they are not a protocol to follow on your own. If you and your prescriber decide a lower-and-slower approach fits you, they can build a schedule around your tolerance and goals.
Compounded products are often involved in microdosing because vials allow fine dose adjustments a fixed-dose pen can’t. Remember that compounded GLP-1s are not FDA-approved for safety, effectiveness, or quality, and use the dose calculator to convert any prescribed microdose into accurate syringe units. This tool is educational, not medical advice.