The Long-Term Side Effects of GLP-1 Drugs: What We Know So Far

GLP-1 receptor agonists—such as Ozempic®, Wegovy®, and Zepbound™—have skyrocketed in popularity for both type 2 diabetes management and weight loss. While many patients see dramatic results, important questions remain: what are the long-term side effects of GLP-1 drugs, and are they safe to take for years?

Recent studies, including new research published in Nature Medicine (Jan 2025), suggest that these medications carry risks beyond short-term nausea or digestive issues. Below, we break down what’s currently known.

How GLP-1 Drugs Work

GLP-1 (glucagon-like peptide-1) is a natural hormone released in the gut after meals. Its role is to:

• Enhance insulin secretion when blood sugar rises
• Reduce glucagon secretion, lowering blood glucose production
• Slow stomach emptying, which promotes satiety
• Reduce appetite, leading to weight loss

Since natural GLP-1 breaks down quickly, drug companies created synthetic GLP-1 receptor agonists (like semaglutide in Ozempic®/Wegovy®) that stay active longer.

While effective, their impact on multiple organs has raised concerns about long-term safety.

Known Long-Term Side Effects of GLP-1 Drugs

1. Gastrointestinal Issues

GI side effects are the most common, especially early on:

• Nausea
• Vomiting
• Diarrhea
• Constipation

These may lessen over time but can persist in some patients, leading to dehydration and nutritional deficiencies.

2. Pancreatitis and Pancreatic Cancer Risk

One of the most serious concerns is pancreatitis.

A 2025 Nature Medicine study of 200,000+ patients found:

• 2.0–2.5x higher risk of drug-induced pancreatitis
• Higher incidence of kidney stones and arthritis

Chronic pancreatitis can permanently damage the pancreas and raises long-term cancer risk.

3. Thyroid Cancer Concerns

In rodent studies, GLP-1 drugs increased thyroid C-cell tumors.

• FDA warning: Patients with a personal/family history of medullary thyroid carcinoma or MEN2 syndrome should avoid these medications.
• Human data: No clear causal link yet, but long-term monitoring is ongoing.

4. Kidney Function Problems

Reports of acute kidney injury have surfaced, often tied to dehydration from vomiting or diarrhea. Patients with pre-existing kidney disease may face added risks.

5. Mental Health and Behavioral Changes

Some patients report:

• Depression
• Mood changes
• Suicidal thoughts

While not yet proven as a direct effect, the FDA advises close monitoring of mental health while on GLP-1 drugs.

6. Muscle Mass Loss

Rapid weight loss often includes loss of lean muscle mass, which may slow metabolism and affect long-term health.

Pairing GLP-1 medications with strength training and high-protein diets may help reduce this risk, but it’s not always enough.

Why These Risks Matter

While GLP-1 drugs can be life-changing, many side effects are dose- and duration-dependent. In other words, the longer you take them, the greater the chance of experiencing complications.

That’s why many obesity specialists view these drugs as short-term tools, not permanent solutions.

Safer Long-Term Alternatives

At BASS Bariatric Surgery Center, we see many patients who turn to us after struggling with GLP-1s. The reality:

• Cost: At $900–$1,500 per month, these drugs can add up to $50,000+ over 5 years.
• Weight regain: Many regain lost weight after stopping.
• Surgery: Bariatric surgery is a one-time procedure with proven long-term success rates and often lower lifetime costs.

If you’re weighing your options, surgery may provide safer, more sustainable results.

FAQs

Q: Are GLP-1 drugs safe to take long-term?‍

A: Current research suggests risks like pancreatitis, kidney problems, and muscle loss may increase with prolonged use. Long-term safety remains under study.

Q: Can GLP-1 medications cause cancer?‍

A: Animal studies show a link to thyroid tumors, but human evidence is unclear. Patients with thyroid cancer history should avoid them.

Q: Is bariatric surgery safer than GLP-1 medications?‍

A: While surgery has risks, it is a permanent, one-time treatment with decades of research supporting long-term effectiveness and safety.

Final Thoughts

GLP-1 drugs like Ozempic® and Wegovy® are powerful tools for weight loss and diabetes management—but they are not risk-free. From pancreatitis to kidney problems, the long-term side effects are only now being fully understood.

If you’re concerned about safety, effectiveness, and cost, bariatric surgery may offer a more reliable path to lasting weight loss.

Contact BASS Bariatric Surgery Center today to learn more about safe, long-term solutions tailored to your needs.