Words
Compounding describes how a preparation is made.
What the word describes
A pharmacist, doctor or registered facility can prepare a drug from ingredients; this process is called compounding. Compounding notes from the US medicine agency (FDA)
A useful next question is why this preparation is being proposed for your particular need.
What the word does not promise
For compounded drugs, FDA does not review how safe, effective or well made they are before sale; they are unapproved, as of September 2026. FDA on compounded-drug risks
That distinction applies to the preparation itself. A licence or a badge answers another question.
Why pharmacy labels differ
503A names the part of federal law for making medicine for an individual patient; the September 2026 rules require a valid prescription identifying that patient. FDA on medicine made for a named patient
A prescription is only part of the check: the raw drug ingredient must also meet the legal ingredient tests.
An ingredient with a published drug-quality standard has to meet that standard. Where no standard is published, it must either be part of an approved drug or have a place on FDA’s list of extra allowed ingredients. FDA’s tests for a pharmacy’s raw ingredients
Ask the pharmacy whether it makes your medicine under 503A and which ingredient test it meets.
You do not have to work it out from a shop sign.
503B is another part of federal law: in September 2026, it allowed registered makers called outsourcing facilities to prepare batches without naming each patient in a prescription. FDA on facilities that make batches
The batches are sterile, meaning free of living germs. These facilities often supply clinics and hospitals.
The batch-making rule does not remove your own prescription requirement when the medicine is a prescription drug.
Ask about the pharmacyGet the maker’s name before checking its records.