What Is Microdose GLP-1?

Sub-Clinical Semaglutide and Tirzepatide for Metabolic Optimization · Last reviewed by the OPTML clinical team on April 29, 2026

Quick answer

Microdose GLP-1 refers to compounded semaglutide or tirzepatide prescribed at sub-clinical doses, typically 0.1-0.25 mg/wk semaglutide or 0.5-2.5 mg/wk tirzepatide — well below the doses studied in the pivotal weight-loss trials of the FDA-approved branded preparations. The intent is metabolic optimization (insulin sensitivity, food-noise reduction, gentle appetite regulation) rather than aggressive weight loss. Brand-name pen formulations cannot deliver these doses; only compounded vial preparations enable this protocol. Compounded preparations are not FDA-approved.

Indications and Goals

Microdose GLP-1 is used by patients who do not meet (or do not want) traditional weight-loss-dose GLP-1 therapy but who would benefit from the metabolic effects of GLP-1 receptor agonism. Common goals:

Typical Microdose Ranges

DrugMicrodose rangeStandard weight-loss titration
Semaglutide0.1 - 0.25 mg/wk0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg/wk
Tirzepatide0.5 - 2.5 mg/wk2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg/wk

Why Brand-Name Pens Cannot Microdose

Wegovy, Ozempic, Mounjaro, and Zepbound are sold in fixed-dose pre-filled pens. The lowest available pen dose for semaglutide (Wegovy) is 0.25 mg/wk, already 2.5× the lowest microdose target. Tirzepatide pens start at 2.5 mg/wk. Compounded vial-and-syringe preparations allow precise volumetric titration.

Mechanism

Both semaglutide and tirzepatide are GLP-1 receptor agonists (tirzepatide is also a GIP receptor agonist). At sub-clinical doses, receptor occupancy is partial, sufficient to:

What Microdose GLP-1 Is Not

Side Effects and Risks

The side-effect profile is generally milder than full-dose GLP-1 therapy, but the same class effects apply: nausea, constipation, fatigue, gallbladder disease, pancreatitis (rare), and a boxed warning for medullary thyroid carcinoma based on rodent data. Patients with personal/family history of MTC or MEN-2 should not use GLP-1 receptor agonists.

Considering microdose GLP-1?

Compounded sema $199/mo · Compounded tirz $299/mo · Custom titration to your goals.

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References

  1. Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021;384(11):989-1002. [STEP 1]
  2. Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide Once Weekly for the Treatment of Obesity. N Engl J Med. 2022;387(3):205-216. [SURMOUNT-1]
  3. Drucker DJ. Mechanisms of Action and Therapeutic Application of Glucagon-like Peptide-1. Cell Metab. 2018;27(4):740-756.
  4. Müller TD, Finan B, Bloom SR, et al. Glucagon-like peptide 1 (GLP-1). Mol Metab. 2019;30:72-130.