Liraglutide Side Effects: Potentially Permanent Adverse Events Explained

Which liraglutide side effects can actually be permanent?

Liraglutide is sold as two separate products: Saxenda, 3 mg once daily for weight management, and Victoza, up to 1.8 mg once daily for type 2 diabetes [1][2]. Both are once-daily subcutaneous injections, and both labels lead with the same boxed warning [1][2].

Neither label describes a side effect as permanent or irreversible. The labeled event that most clearly leaves a permanent change is gallbladder disease that ends in cholecystectomy; the Saxenda label states that the majority of treated patients with cholelithiasis or cholecystitis required cholecystectomy [1]. Both labels also describe acute pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing pancreatitis [1][2]. Victoza's label records postmarketing reports of acute kidney injury, in some cases requiring hemodialysis, but does not say whether the kidney damage persisted [2].

Nausea, vomiting, diarrhea and constipation were the most frequent reactions in Saxenda trials, and nausea declined as treatment continued [1].

Thyroid C-cell tumors: the boxed warning

Liraglutide caused dose-dependent and treatment-duration-dependent thyroid C-cell tumors, including carcinomas, in both sexes of rats and mice at clinically relevant exposures [1][2]. The label then states that it is unknown whether Saxenda causes thyroid C-cell tumors, including medullary thyroid carcinoma (MTC), in humans, because the human relevance of the rodent finding has not been determined [1]. Victoza's label carries the same language [2].

Cases of MTC in patients treated with liraglutide have been reported in the postmarketing period, and the label states that the data in those reports are insufficient to establish or exclude a causal relationship [1][2].

Both labels contraindicate liraglutide in people with a personal or family history of MTC or with Multiple Endocrine Neoplasia syndrome type 2 [1][2]. Routine serum calcitonin measurement or thyroid ultrasound is described in the label as of uncertain value for early detection, and may increase the risk of unnecessary procedures because of low test specificity and the high background incidence of thyroid disease [1]. The label adds that a significantly elevated calcitonin may indicate MTC and that patients with MTC usually have values above 50 ng/L [1].

The label lists these symptoms of thyroid tumors for patient counseling: a mass in the neck, dysphagia, dyspnea, and persistent hoarseness [1].

Pancreatitis: fatal and non-fatal cases

Both labels warn that acute pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing pancreatitis, has been observed in patients treated with GLP-1 receptor agonists including liraglutide [1][2]. The warning describes persistent or severe abdominal pain, sometimes radiating to the back, which may or may not be accompanied by nausea or vomiting. The labels say to discontinue the drug and start appropriate management if pancreatitis is suspected [1][2].

The Victoza label's adverse reactions section records 13 cases of pancreatitis among Victoza-treated patients in glycemic control trials [2].

Necrotizing pancreatitis means that part of the pancreas dies. The labels name this form but do not say whether any case left lasting damage [1][2].

Gallbladder disease: the clearest route to surgery

In Saxenda's adult trials, cholelithiasis (gallstones) was reported in 2.2% of Saxenda-treated patients versus 0.8% of placebo patients, and cholecystitis (gallbladder inflammation) in 0.8% versus 0.4% [1]. The majority of Saxenda-treated patients with these events required cholecystectomy, which removes the gallbladder [1].

The label also notes that substantial or rapid weight loss can increase the risk of cholelithiasis, but that the incidence of acute gallbladder disease was greater in Saxenda-treated patients than in placebo patients even after accounting for the degree of weight loss [1]. When cholelithiasis is suspected, the label calls for gallbladder studies and appropriate clinical follow-up [1].

Acute kidney injury

The Victoza label records postmarketing reports of acute kidney injury, in some cases requiring hemodialysis; most of the reported events occurred in patients who had gastrointestinal reactions leading to dehydration, such as nausea, vomiting, or diarrhea [2]. It instructs monitoring of renal function in patients reporting reactions that could lead to volume depletion, especially during initiation and dose escalation [2]. Saxenda's label lists acute kidney injury due to volume depletion as a warning and gives the same monitoring instruction [1].

Heart rate increase

Saxenda's label reports mean increases in resting heart rate of 2 to 3 beats per minute with routine clinical monitoring, compared with placebo [1]. More Saxenda-treated patients had changes from baseline above 10 bpm at two consecutive visits (34% versus 19%) and above 20 bpm (5% versus 2%); at least one resting heart rate above 100 bpm was recorded in 6% versus 4%, and tachycardia was reported as an adverse reaction in 0.6% versus 0.1% [1]. In a clinical pharmacology trial that monitored heart rate continuously for 24 hours, Saxenda treatment was associated with a heart rate 4 to 9 bpm higher than placebo [1].

The label's instruction is to monitor heart rate at regular intervals [1].

Suicidal thoughts: the warning was removed in 2026

An earlier Saxenda label, dated 26 January 2024, carried a Warnings and Precautions item on suicidal behavior and ideation, advising monitoring for depression or suicidal thoughts and discontinuation if symptoms developed [4]. That wording has changed. On 13 January 2026 the FDA requested that the makers of Saxenda, Wegovy and Zepbound remove the suicidal ideation and behavior language, after a review that included a meta-analysis of 91 placebo-controlled GLP-1 receptor agonist trials covering 107,910 patients and a claims cohort of 2,243,138 new users [3]. The FDA stated that it found no increased risk of suicidal ideation and behavior with these medications [3].

The current Saxenda label, effective 25 February 2026, no longer contains a suicidal behavior and ideation warning, and the word does not appear in the label text; the Victoza label does not include it either [1][2]. One trace remains: a depression adverse reaction appears in the pediatric trial table at 4% on Saxenda versus 2.4% on placebo [1]. In the 56-week adolescent trial, one suicide occurred in the liraglutide group and was judged by the investigator as unlikely related to treatment [5].

Other labeled reactions

Injection-site reactions were reported by 13.9% of Saxenda-treated adults versus 10.5% on placebo [1], and by about 2% of Victoza-treated adults, with fewer than 0.2% discontinuing because of them [2]. Serious hypersensitivity reactions, including anaphylaxis and angioedema, appear as postmarketing reports; Saxenda's label directs discontinuation [1], while Victoza's directs treatment per standard of care and monitoring until signs and symptoms resolve [2]. Alopecia is listed among postmarketing skin reactions in the Saxenda label with frequency not established, and it does not appear in the trial tables [1]. Pulmonary aspiration during general anesthesia or deep sedation has been reported with GLP-1 receptor agonists, and both labels instruct patients to tell healthcare providers about planned surgeries or procedures [1][2].