FDA adds Zepbound to the drug shortage list

FDA added Zepbound (tirzepatide) injection pens to its national drug shortage list in April 2024, about five months after the weight-management drug was approved, with high demand cited as the reason ^[2]. The listing mattered beyond pharmacy inventories: under federal law, a drug's presence on the shortage list is one of the conditions that allows compounding pharmacies and outsourcing facilities to make their own versions of an FDA-approved medicine ^[1].

What was listed, and what wasn't

Zepbound pens were approved in November 2023 under NDA 217806 and added to the shortage list in April 2024 ^[2]. That put the obesity brand alongside its sibling, Mounjaro (also tirzepatide), whose pens were approved in May 2022 and added to the shortage list in December 2022, also because of high demand ^[2]. FDA's records date the start of the tirzepatide injection shortage to December 15, 2022 ^[2].

Not every tirzepatide presentation was affected. Zepbound single-dose vials were approved in a supplement to NDA 217806 in March 2024, but only the 2.5 mg and 5 mg strengths were being marketed in the United States, and the vial products have never appeared on the shortage list ^[2]. Mounjaro single-dose vials, approved in July 2023, were not marketed in the U.S. and were never on the list either ^[2]. Both brands are sold in the same six pen strengths: 2.5, 5, 7.5, 10, 12.5 and 15 mg per 0.5 mL ^[2].

Why the shortage list drives compounding

Federal compounding rules turn on the shortage list in two places. Under section 503A, a state-licensed pharmacy or physician generally cannot compound, regularly or in inordinate amounts, drugs that are "essentially copies" of a commercially available product ^[1]. FDA considers a compounded product essentially a copy when it has the same active ingredient at the same, similar or easily substitutable strength and can be given by the same route as the approved drug, unless a prescriber documents a significant difference for a specific patient ^[1]. Under section 503B, outsourcing facilities may not compound from bulk active ingredient unless that substance is on the 503B bulks list, or the drug is on FDA's shortage list at the time of compounding, distribution and dispensing ^[1].

So when Zepbound joined the list in April 2024, the same shortage-based pathway that had already covered Mounjaro extended to the obesity brand.

Why it matters for patients

For people who could not find Zepbound pens in the spring of 2024, the listing explained both the empty shelves and the sudden availability of cheaper compounded tirzepatide sold through telehealth companies and clinics. Compounded drugs are not FDA-approved: the agency does not review them for safety, effectiveness or manufacturing quality before they reach patients, and FDA has said it can still act on violations such as findings that a product is of substandard quality or otherwise unsafe ^[1].

The other consequence is impermanence. Access built on a shortage listing lasts only as long as the shortage. FDA has acknowledged that even after a shortage is declared resolved, patients and prescribers may still see intermittent, localized supply gaps as products move from manufacturers through wholesalers to local pharmacies ^[2].

What happens next

FDA removed tirzepatide injection products from the shortage list on October 2, 2024, was sued on October 7, 2024, in the Northern District of Texas by the Outsourcing Facilities Association and a compounder, and the decision was remanded to the agency on October 11, 2024 ^[2]. On December 19, 2024, FDA again determined the tirzepatide shortage was resolved, giving 503A compounders until February 18, 2025, and 503B outsourcing facilities until March 19, 2025, before enforcement discretion ended ^[1][2]. FDA declared the semaglutide injection shortage resolved on February 21, 2025, with parallel deadlines of April 22 and May 22, 2025 ^[1]. Courts denied preliminary injunctions on March 5, 2025, and April 24, 2025 ^[1]. As of FDA's April 1, 2026 update, neither tirzepatide nor semaglutide appears on the 503B bulks list or the shortage list ^[1].