Few drug classes have disrupted pharmacy operations as thoroughly as GLP-1 receptor agonists. Since early 2022, medications like semaglutide (marketed as Ozempic for diabetes and Wegovy for weight loss) and tirzepatide (marketed as Mounjaro for diabetes and Zepbound for weight loss) have created supply chain challenges that pharmacies across North America have never seen before.
The story of GLP-1 shortages is ultimately a story about what happens when demand for a medication class explodes beyond anything manufacturers anticipated.
How GLP-1s Work
GLP-1 receptor agonists mimic the action of glucagon-like peptide-1, a hormone that stimulates insulin secretion, suppresses glucagon release, slows gastric emptying, and promotes satiety. Originally developed and approved for type 2 diabetes, these medications were found to produce significant weight loss as a secondary effect.
Semaglutide, manufactured by Novo Nordisk, was first approved as Ozempic for type 2 diabetes. A higher-dose formulation was later approved as Wegovy for chronic weight management. Tirzepatide, manufactured by Eli Lilly, works on both GLP-1 and GIP receptors and was approved as Mounjaro for diabetes and Zepbound for weight loss.
Clinical trials showed weight loss of 15% to 22% of body weight with these medications, results that no previous weight loss drug had achieved. The clinical data, combined with widespread media coverage and social media attention, triggered a surge in demand that manufacturers were not prepared to meet.
The Shortage
Shortages of semaglutide products began appearing in early 2022 and persisted for nearly three years. At various points, specific doses of Ozempic and Wegovy were unavailable for weeks or months. Tirzepatide products experienced similar intermittent shortages.
The root cause was straightforward: manufacturing capacity could not keep up with demand. Biologic injectable medications like GLP-1 agonists require specialized manufacturing facilities, and scaling production takes years, not months. Novo Nordisk invested billions in expanding its manufacturing infrastructure, but the gap between supply and demand persisted.
For pharmacies, the shortage created daily operational headaches. Patients would call multiple pharmacies searching for their medication. Pharmacists spent hours on the phone with wholesalers trying to source specific doses. Some patients had their therapy interrupted, raising concerns about glycemic control for diabetes patients and weight regain for those using the medications for obesity.
Compounding Pharmacies Fill the Gap
With brand-name products unavailable or unaffordable, compounding pharmacies stepped in. Compounded semaglutide became widely available at prices ranging from $100 to $300 per month, a fraction of the $1,000 or more per month cost of brand-name products.
The compounding market grew rapidly, but it also raised questions. The FDA and Health Canada expressed concerns about the quality, sterility, and dosing accuracy of some compounded GLP-1 products. Reports of adverse events linked to compounded semaglutide prompted regulatory scrutiny.
Compounding pharmacies argued they were filling a legitimate medical need during a declared shortage. Manufacturers argued that compounded versions posed safety risks and infringed on their intellectual property.
The Shortage Winds Down
In December 2024, tirzepatide was removed from the FDA's drug shortage list, signaling that Eli Lilly had finally caught up with demand for Mounjaro and Zepbound. In February 2025, semaglutide followed, with the FDA removing it from the shortage list as well.
The end of the official shortage has significant implications for compounding pharmacies. Under U.S. law, compounding pharmacies can produce copies of FDA-approved drugs only when those drugs are on the official shortage list. With semaglutide and tirzepatide no longer listed, compounding pharmacies face legal pressure to stop producing these medications.
Canadian Market Impact
In Canada, the supply situation has followed a similar trajectory. Health Canada has maintained a Drug Shortages Canada database tracking GLP-1 availability. Canadian pharmacies experienced the same sourcing challenges as their American counterparts, though the smaller market size meant shortages were sometimes less severe.
Canadian patients face a different affordability challenge. Provincial drug plans have been cautious about covering GLP-1 agonists for weight loss, with most public plans limiting coverage to the diabetes indication. Patients seeking these medications for weight management often pay out of pocket or rely on private insurance, where coverage varies widely.
What Pharmacies Should Prepare For
Continued high demand. Even with manufacturing capacity increasing, demand for GLP-1 agonists is expected to remain strong. Some analysts project the GLP-1 market will exceed $100 billion globally by 2030.
New entrants. Several pharmaceutical companies are developing next-generation GLP-1 and multi-receptor agonists, including oral formulations that could further expand the market.
Insurance and coverage changes. As clinical evidence accumulates showing long-term cardiovascular and metabolic benefits of GLP-1 agonists, pressure on public and private insurers to expand coverage will increase.
Patient counseling needs. Pharmacists play a critical role in educating patients about realistic expectations, proper injection technique, side effect management, and the importance of combining medication with lifestyle changes for sustained results.
The GLP-1 revolution has permanently changed the pharmacy landscape. The supply chain challenges of the past three years have tested pharmacy operations, but they have also demonstrated the profession's ability to adapt under pressure.