Made to order still calls for a reason

What making a medicine to order involves

Compounding is the process of a doctor or pharmacist preparing a patient’s medicine instead of supplying the finished product made by a drug company.

FDA means Food and Drug Administration, the US agency that approves medicines.

In the explanation checked on September 26, 2026, FDA describes compounding as an option when approved medicine is unavailable or cannot meet the patient’s need; the resulting medicine is not FDA-approved.

Find out who would make your medicine

A pharmacy or doctor making it for you

Under US law section 503A, a licensed doctor or pharmacist can prepare medicine when a valid prescription identifies the particular patient. The maker must also meet the law’s other requirements, as checked on September 26, 2026.

503A is the number of that part of the law. Having a prescription is one requirement; it does not make every mixture legal. Ask the pharmacy to explain why it can legally make your particular medicine, including which ingredients may be used and the rules for copies explained below.

A place making batches for clinics or hospitals

Under US rules checked on September 26, 2026, a “503B outsourcing facility” is a place registered with FDA to make sterile medicines. That business may prepare them without prescriptions naming individual patients.

Sterile means free of living germs. This kind of business makes batches of medicine, often for clinics or hospitals. The number 503B names its part of the law; “outsourcing” means the clinic or hospital gets the medicine made elsewhere.

Supplying a prescription medicine to a patient still requires a valid prescription from someone licensed to prescribe, under the US rule recorded as of September 26, 2026.

The business gains no recommendation from FDA and none of its medicines gains approval by joining FDA’s register, as checked on September 26, 2026.

Ask about a copy before comparing its price

US law limits making compounded copies of available medicines, with different rules for 503A pharmacies and 503B facilities, as of September 26, 2026.

For 503A, the person prescribing may identify a change that matters significantly for one patient; without that difference, the law bars regular or large-scale compounding of essentially identical copies.

When FDA decides whether there is a medical need to use an ingredient for 503B compounding, lower cost or easier use does not count as that need, as of September 26, 2026.

This is a decision about what the business may make, not a test you take. Ask why the person prescribing considers this exact medicine suitable for you and which rule allows it.