Every price on this site is a compounded price, so the question of whether compounded products behave differently from manufactured ones is not academic here. A 2026 pharmacovigilance study went looking in the FDA’s Adverse Event Reporting System, covering 2018 to 2024, and found 707 reports involving compounded GLP-1 products out of 81,078 in total [1]. What it measured, and what that measurement can and cannot say, are two different things — and the second is most of this article. Every figure on the ranked board is a compounded one, so this is the trade underneath all of them.
What was reported more often
The study calculated reporting odds ratios with confidence intervals, adjusted by logistic regression. Compounded products showed higher reporting odds for preparation errors, at 48.92 (95% CI 12.63 to 189.6); contamination, at 19.00 (95% CI 4.24 to 85.03); compounding or manufacturing issues, at 8.51 (95% CI 5.17 to 14.0); and prescribing errors, at 4.46 (95% CI 2.49 to 7.98). Hospitalization odds were 2.35 (95% CI 1.94 to 2.83).
Among clinical events, the higher reporting odds were suicidality at 6.34 (95% CI 4.32 to 8.99), cholecystitis at 3.39 (95% CI 1.61 to 6.31), abdominal pain at 2.84 (95% CI 2.29 to 3.49), diarrhea at 1.59 and nausea at 1.27.
The finding that cuts the other way
Compounded products showed lower reporting odds for administration errors, at 0.29 (95% CI 0.16 to 0.53), and for dosing errors, at 0.24 (95% CI 0.17 to 0.32). That sits awkwardly beside the poison-control case series covered separately here, in which two of three reported harms were ten-fold dosing errors on compounded vials.
Both can be true. They are different surveillance systems with different reporting pathways, and a patient who mis-doses a compounded vial bought through telehealth may be more likely to call a poison center than to generate a FAERS report naming the product. What neither can do is tell you how often it happens. This article is not going to resolve the tension by choosing the more alarming half.
What a buyer can actually use
The quality-related signals — preparation, contamination, manufacturing — are the ones with the clearest mechanism behind them, because they describe the part of the supply chain that differs by definition. A compounded preparation is made to order in a pharmacy the FDA has not reviewed for that product. That is the trade every price on this site is built on, and it is worth knowing you are making it.
Two practical consequences. A named compounding pharmacy is worth more than a low price, because it is the only thing that makes the supply chain checkable at all. And a seller that publishes neither its pharmacy nor what happens to the price at a higher dose is asking for trust in two places at once. The ranked board shows which sellers publish what, and the price distribution shows what the compounded discount actually is.
Price figures are computed from this site’s own records at build time, most recently read September 2026, across 456 priced sellers. The reporting figures are cited and are not this site’s own.