FDA adds tirzepatide injection to the drug shortage list

FDA added tirzepatide injection products to its national drug shortage list on December 15, 2022, after demand for Eli Lilly's Mounjaro outpaced supply ^[3]. The listing was more than a supply notice: under federal law, it removed the main legal barrier that keeps compounding pharmacies from making copies of an FDA-approved drug ^[2].

Mounjaro's prefilled single-dose pens were approved in May 2022 under NDA 215866 in six strengths — 2.5 mg/0.5 mL, 5 mg/0.5 mL, 7.5 mg/0.5 mL, 10 mg/0.5 mL, 12.5 mg/0.5 mL and 15 mg/0.5 mL — and were added to the shortage list in December 2022 "due to high demand" ^[3]. Mounjaro single-dose vials in the same strengths were later approved in July 2023 but were not marketed in the United States and have never appeared on the shortage list ^[3].

FDA defines a shortage as "a period of time when the demand or projected demand for the drug within the United States exceeds the supply of the drug," and the agency judges that at the national level across the entire market, not pharmacy by pharmacy ^[3]. The agency is required to keep an up-to-date public list of drugs it determines are in shortage ^[3].

What the listing changed for compounders

Under section 503A of the Federal Food, Drug, and Cosmetic Act, state-licensed pharmacies and physicians generally may not compound drugs that are "essentially copies" of commercially available products on a regular basis or in inordinate amounts ^[2]. But a drug is not considered commercially available while it is on FDA's shortage list, so that restriction does not apply during a shortage ^[2]. All other 503A conditions still apply, including compounding based on a valid prescription for an individual patient ^[2].

For 503B outsourcing facilities, the shortage listing does two things. It lifts the restriction on making identical or nearly identical copies of an approved drug, and it allows the facility to use a bulk drug substance — the active pharmaceutical ingredient — to make that drug ^[2]. Outside of a shortage, an outsourcing facility can only compound from a bulk substance if that substance is on FDA's 503B bulks list ^[1].

FDA has been consistent that compounded versions are not equivalent to the brand. The agency says compounded drugs "pose a higher risk than FDA-approved drugs because compounded drugs do not undergo FDA review for safety, effectiveness or quality before they are marketed," and recommends patients be prescribed an FDA-approved drug when one is available and appropriate ^[2].

Why it matters for patients

The December 15, 2022 listing is the origin point of the compounded tirzepatide market that many US patients encountered over the following two years. It explains why telehealth companies and compounding pharmacies could legally offer tirzepatide at all, and why that availability was always tied to a status FDA could change.

It also means the legal ground under a compounded prescription can shift without the patient doing anything. FDA's policy allows flexibility for outsourcing facilities filling orders received while a drug was in shortage, but the agency may act if a facility keeps filling new orders after the drug comes off the list, or keeps filling existing orders more than 60 days after removal ^[2].

What happened next

FDA removed tirzepatide from the shortage list on October 2, 2024 ^[3]. On October 7, 2024, the agency was sued in the Northern District of Texas by the Outsourcing Facilities Association and North American Custom Laboratories (doing business as Farmakeio Custom Compounding), and on October 11 a court order remanded the decision back to FDA for reevaluation ^[3]. FDA reaffirmed the shortage was resolved on December 19, 2024, giving 503A compounders until February 18, 2025 and 503B facilities until March 19, 2025 before enforcement resumed ^[1][3]. FDA declared the separate semaglutide injection shortage resolved on February 21, 2025, with parallel deadlines of April 22 and May 22, 2025 ^[1]. As of April 1, 2026, FDA states that neither tirzepatide nor semaglutide appears on the 503B bulks list or the drug shortage list ^[1].