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Compound

GLP-1 Receptor Agonists

Prescription peptide drug class

FDA-approved (brand drugs)Compounded versions under FDA enforcementWADA-monitored

What it is

GLP-1 receptor agonists are peptide-based molecules that mimic the gut hormone glucagon-like peptide-1, which regulates appetite and glucose handling.[1] Tirzepatide additionally acts on the GIP receptor. The approved brand drugs in this class are FDA-overseen prescription medications — a meaningfully different regulatory category from 'research use only' peptides.[1]

Regulatory status

Brand-drug formulations are FDA-approved for specified indications. After the 2025 resolutions of the semaglutide and tirzepatide shortages, the FDA wound down the temporary mass-compounding latitude and issued warnings to more than fifty compounders over the course of the year.[2] The class is currently on the WADA Monitoring Program rather than the Prohibited List.[3]

State of the evidence

Large randomized trials document weight reduction in approved indications. A notable share of the weight lost is lean tissue, which complicates naive performance interpretations. No established performance benefit in healthy, trained adults.[1]

Sources

  1. [1]FDA, 'FDA's concerns with unapproved GLP-1 drugs used for weight loss.'
  2. [2]FDA, 'FDA clarifies policies for compounders as national GLP-1 supply begins to stabilize.'
  3. [3]WADA, 'Prohibited List.'

Educational reference only. Not medical advice. No dosing or protocols are published here.

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