For decades, the FDA made it nearly impossible to know which factories were manufacturing your generic medications. ProPublica built a tool to show you. Here’s how we did it.

Look up your prescriptions using the tool here.

Our ongoing reporting has focused on the safety of generic drugs, which represent the vast majority of all prescriptions filled in the United States. Thus, Rx Inspector does not include brand-name or over-the-counter drugs, at least for now. We excluded gases (like oxygen tanks) and intradermal route drugs (many of these were allergy tests for things like feline hair).

ProPublica described the app and the methodology used to build it to the FDA, which did not comment. The agency previously told ProPublica that it doesn’t reveal where drugs are made on inspection reports to protect what it deemed confidential commercial information.