Compounding during drug shortages, and the rules that switch on when a drug is listed

On November 3, 2026, FDA's drug shortage list showed 69 drugs in current shortage. Forty-nine of them were injections, or 71 percent, according to GxRadar's analysis of openFDA's drug shortage data¹. The median current shortage had been on the list for 1,710 days.

Each of those listings carries a legal consequence that has nothing to do with the manufacturer who reported it. Under federal compounding law, a drug that is on FDA's shortage list is treated as not commercially available, and that lifts the main restriction on pharmacies and outsourcing facilities making copies of it. "Generally, when an FDA approved drug is on FDA's drug shortages list some federal law restrictions may not apply, such as restrictions on compounding drugs that are essentially copies of approved drugs," FDA says on its page on compounding during shortages².

That switch decided how the GLP-1 shortages played out from 2022 to 2025, and it governs how hospitals cover gaps in sterile injectables today. This piece explains what the listing changes under sections 503A and 503B of the Federal Food, Drug, and Cosmetic Act, what it leaves in place, and how FDA handled the end of the semaglutide and tirzepatide shortages. For the basic differences between the two kinds of compounder, see our explainer on 503A and 503B compounding.

What the listing changes for pharmacies under 503A

Section 503A covers state-licensed pharmacies and physicians who compound for individual patients. One of its conditions is that the compounder "does not compound regularly or in inordinate amounts (as defined by the Secretary) any drug products that are essentially copies of a commercially available drug product," in the words of 21 U.S.C. 353a(b)(1)(D)³.

FDA's January 2018 guidance on essentially copies under 503A⁵ fills in the terms. A product is not commercially available if it has been discontinued or if it "appears on the FDA drug shortage list in effect under section 506E," which the guidance defines as being in "currently in shortage" status in FDA's database, and not in resolved status. Outside a shortage, FDA says it will not act against a pharmacy that fills "four or fewer prescriptions" a month for a copy, and prescriptions documenting a prescriber's determination of a significant difference for the patient do not count toward that number.

A listing does not remove the rest of 503A. The drug must still be compounded for an identified patient on a valid prescription, a condition FDA restates on the shortage compounding page². Restrictions on ingredients, on drugs withdrawn for safety reasons and on insanitary conditions also continue to apply.

What the listing changes for outsourcing facilities under 503B

Outsourcing facilities, created by the 2013 Drug Quality and Security Act, can make batches without patient-specific prescriptions and must meet current good manufacturing practice requirements. For them the shortage list opens two doors in the statute.

The first concerns raw ingredients. An outsourcing facility may compound from a bulk drug substance only if that substance is on FDA's list of bulk substances with a clinical need or if "the drug compounded from such bulk drug substance appears on the drug shortage list in effect under section 356e of this title at the time of compounding, distribution, and dispensing," under 21 U.S.C. 353b(a)(2)(A)⁴. FDA maintains the clinical-need list on its bulk drug substances page⁷.

The second concerns copies. Section 503B bars outsourcing facilities from making a drug that is "essentially a copy of one or more approved drugs," and the statute's definition carves out an approved drug that is on the shortage list at the same three moments. FDA's 2018 guidance on essentially copies under 503B⁶ adds a grace period. A facility may fill orders it received while the drug was listed, provided the drug was on the list within 60 days of distribution or dispensing, because a shortage can end while a sterile batch is still waiting for test results. FDA "may take regulatory action" if a facility keeps taking new orders after delisting.

Sources: 21 U.S.C. 353a and 353b; FDA's 2018 essentially-copies guidances; FDA's shortage compounding page².

What the listing does not change

A compounded drug made during a shortage is still not an approved drug. "Compounded drugs are not FDA-approved," the agency says in its compounding questions and answers⁸, which means FDA "does not verify the safety, effectiveness or quality of compounded drugs before they are marketed." It is also not a generic. A generic is approved under section 505(j) after showing it matches the brand, as our explainer on generic approval describes.

Nor does a listing create capacity. FDA notes that compounders "may not have the expertise or equipment" to make certain drugs, "or may have business reasons not to do so." That matters for the current list, which is dominated by sterile injectables that are hard to make in small batches. Among them is methylprednisolone acetate injection, listed in current shortage since December 15, 2021, according to FDA's shortage list. Contaminated compounded steroid injections, which CDC's outbreak page¹³ ties to methylprednisolone products, caused the 2012 fungal meningitis outbreak, with 753 cases and 64 deaths in 20 states.

A temporary policy for hospitals

Sometimes FDA goes further than the statute. In October 2024, after supply of intravenous fluids was disrupted, the agency issued temporary policies for compounding certain parenteral drug products⁹. For drugs on a list FDA posted, it said it would not act against a state-licensed pharmacy, including a hospital pharmacy, that supplied a hospital without a patient-specific prescription or made a copy of a commercially available drug, if the pharmacy used FDA's default beyond-use dates, notified state regulators and met other conditions. Outsourcing facilities got a separate policy covering drugs on a companion list within 180 days of compounding or distribution. The guidance says the policy is meant to last only as long as the supply disruption, and FDA encourages hospitals that need compounded products to get them from outsourcing facilities. Our account of the 2024 IV fluid shortage covers the events behind it.

How the GLP-1 shortages ended

Semaglutide and tirzepatide were the largest test of the switch, and the dates show how FDA turned it off.

Sources: FDA's declaratory orders on tirzepatide (December 19, 2024)¹⁰ and semaglutide (February 21, 2025)¹¹, and the agency's running statement on compounders and GLP-1 supply¹².

After the semaglutide decision, FDA gave pharmacies 60 days and outsourcing facilities 90 days to wind down. Compounders challenged both decisions in federal court in Texas, and FDA tied its final dates to the court's rulings; the court denied preliminary injunctions on March 5, 2025, for tirzepatide and April 24, 2025, for semaglutide, the statement says. Our earlier piece on the GLP-1 shortages and compounding has the longer history.

FDA's most recent update, dated April 1, 2026, reminds compounders that adding a second ingredient does not by itself escape the copies rule. The agency said it may treat a product combining semaglutide with vitamin B12 as essentially a copy when it is given the same way and the amounts are within 10 percent of the strengths of commercially available products.

What to watch

Not every GLP-1 has left the list. Liraglutide injection was still in current shortage as of November 3, 2026, with the status first posted on July 18, 2023, in GxRadar's copy of FDA's shortage data¹. When it is resolved, the 503A copy limit returns for pharmacies and the 60-day order policy applies to outsourcing facilities. Readers can follow status changes on our shortage tracker, read how to read FDA's shortage database, or see how FDA uses temporary importation as a separate shortage tool. FDA's general guidance remains that patients be prescribed an approved drug "when available and appropriate," and questions about a specific compounded product belong with the prescriber or pharmacist. More policy coverage is on our law and policy desk.