Liraglutide

Definition

Liraglutide is a GLP-1 receptor agonist and the oldest member of that class in this index. It is administered once daily rather than weekly, which is the practical difference a reader will notice against semaglutide and tirzepatide, and which is also why it has largely been displaced commercially.

It holds two separate approvals under two brand names for two different purposes, and a generic version has existed since 2024. Its regulatory record is the most complete of any molecule here, and the only one whose supply problem has not been declared over.

Evidence

The trial literature is large and belongs to an approved product. Across three name variants PubMed returns 5,901 indexed records, of which 3,668 carry the Humans subject heading, 632 the clinical-trial publication type, and 575 the randomized-controlled-trial type ^[1]. A literature of that size is reported as a magnitude; this index did not itemize it.

The registrational anchor for weight management is a 56-week randomized controlled trial of 3.0 mg daily in adults with overweight or obesity, published in 2015 ^[2]. The approved indications state what the evidence was accepted for: glycemic control in type 2 diabetes and reduction of major adverse cardiovascular events in adults with established cardiovascular disease for one product ^[3], and chronic weight management alongside a reduced-calorie diet and increased physical activity for the other ^[4].

Both labels carry the same limitation of use, and it is the one most often ignored in practice: the products contain liraglutide, and coadministration with other liraglutide-containing products is not recommended ^[3][4].

Side effects

The Saxenda label lists the adverse reactions reported in at least 5 percent of treated patients: nausea, diarrhea, constipation, vomiting, injection site reactions, headache, hypoglycemia, dyspepsia, fatigue, dizziness, abdominal pain, increased lipase, upper abdominal pain, fever and gastroenteritis ^[9]. In the adult weight-management trials, 9.8 percent of treated patients stopped because of an adverse reaction against 4.3 percent on placebo, and nausea was the most common reason ^[9]. The Victoza label, written for type 2 diabetes, names nausea, diarrhea, vomiting, decreased appetite, dyspepsia and constipation as its most common reactions ^[10].

Both labels carry a boxed warning for thyroid C-cell tumors. Liraglutide caused them in rats and mice, whether it does so in humans is unknown, and postmarketing reports of medullary thyroid carcinoma in treated patients are insufficient to establish or exclude a causal link ^[9][10]. The drug is contraindicated for anyone with a personal or family history of medullary thyroid carcinoma or with multiple endocrine neoplasia syndrome type 2, and for anyone with a prior serious hypersensitivity reaction to liraglutide ^[9].

The other warnings cover acute pancreatitis, including fatal hemorrhagic or necrotizing cases; acute gallbladder disease, with gallstones reported in 2.2 percent of Saxenda-treated adults against 0.8 percent on placebo; hypoglycemia when combined with insulin or an insulin secretagogue; a rise in resting heart rate; acute kidney injury after dehydration from vomiting or diarrhea; severe gastrointestinal reactions; serious allergic reactions; and pulmonary aspiration during general anesthesia or deep sedation ^[9]. The Saxenda label does not recommend the drug for people with severe gastroparesis ^[9].

Generic liraglutide carries the same boxed warning as the brand it references ^[11].

Educational summary of the cited sources, not medical advice; a prescriber weighs these risks against a person’s own history.

Lawful access

The lawful route is the approved product, and there are now several. FDA approved liraglutide as Victoza under new drug application 022341, effective January 25, 2010, and as Saxenda under new drug application 206321, effective December 23, 2014 ^[3][4]. On December 23, 2024 it approved the first generic liraglutide injection referencing Victoza, and noted in its own announcement that liraglutide injection and certain other GLP-1 medicines were then in shortage ^[5].

The shortage has not been declared resolved. FDA's drug shortage database lists liraglutide injection with a status of currently in shortage and a date first posted of July 18, 2023 ^[6]. On the date this page was checked, two generic manufacturers reported both presentations available while the brand manufacturer reported limited availability, with one product available until a stated discontinuation in January 2027 and the other delayed in shipping with no estimated duration ^[6]. That distinguishes this molecule from semaglutide and tirzepatide, whose shortages FDA has formally resolved.

The compounding consequence follows from the statute rather than from any liraglutide-specific announcement, and this index does not invent one: FDA's published statements on compounded GLP-1 drugs address semaglutide, tirzepatide, retatrutide and cagrilintide by name and do not address liraglutide ^[7]. What can be said without inference is that liraglutide is a component of approved drug products, which is the condition section 503A sets for compounding from a bulk substance without bulks-list listing, and that it appears in no category of the 503A bulks list published on May 14, 2026 ^[8]. The approved page states how the copy rule works.

Related molecules

Liraglutide joins the GLP-1 receptor agonists alongside semaglutide and tirzepatide, whose shortages ended, and retatrutide, which has no approval at all — four molecules of one class occupying three different supply positions. The 2026 record carries the dated sequence, and the approved peptide drugs table places this product beside the rest of the approved set. The review of peptides for weight loss by US legal status sets it beside every other molecule marketed for weight.

Elsewhere in this index