Adlyxin (Lixisenatide) Side Effects: What to Expect and When to Call Your Doctor

Adlyxin (lixisenatide) was a once-daily injectable GLP-1 receptor agonist for type 2 diabetes that was discontinued in the US in January 2023. While patients can no longer access standalone Adlyxin at US pharmacies, many are researching its side effect profile before considering Soliqua 100/33 (which contains lixisenatide) or switching to another GLP-1. This guide covers what to expect, which side effects require prompt medical attention, and how the profile compares to alternatives.

Most Common Adlyxin Side Effects (≥5% of Patients)

In clinical trials of lixisenatide involving 2,869 patients with a mean exposure of 21.7 weeks, the following adverse reactions occurred in at least 5% of patients:

Nausea — The most common side effect; typically occurs when starting therapy or increasing dose; usually improves within the first 2–4 weeks

Vomiting — Related to lixisenatide's potent gastric emptying inhibition; administer with the first meal to reduce risk

Headache — Reported in ≥5% of patients; generally mild

Diarrhea — A common GI side effect shared across the GLP-1 class

Dizziness — May relate to fluid shifts, reduced oral intake during nausea, or hypoglycemia episodes

Hypoglycemia — Particularly when used with sulfonylureas (14.5% on Adlyxin vs 10.6% on placebo) or basal insulin (47.2% vs 21.6% on placebo)

Less Common but Notable Side Effects

Dyspepsia (3.2%) — Indigestion and stomach discomfort, particularly around meal times

Constipation (2.8%) — GI slowing due to reduced gastric motility

Abdominal distension (2.2%) and upper abdominal pain (2.2%) — GI discomfort that often improves with time

Injection site reactions — Itching, redness, or discomfort at the injection site; more common in patients who develop anti-lixisenatide antibodies

Serious Side Effects: When to Seek Immediate Care

Seek emergency medical care or call your doctor immediately if you experience any of the following:

Anaphylaxis or severe allergic reaction: Occurred in 0.2% of Adlyxin patients (16 per 10,000 patient-years). Symptoms include skin rash, throat tightening, difficulty breathing, rapid heartbeat, or dizziness. Stop the medication and call 911

Pancreatitis: Severe, persistent abdominal pain that may radiate to the back, with or without vomiting. If pancreatitis is confirmed, do not restart lixisenatide. Cases of acute, hemorrhagic, and necrotizing pancreatitis have been reported post-approval

Acute kidney injury: Severe GI side effects (nausea, vomiting, diarrhea) can lead to dehydration and acute kidney injury. Call your doctor if GI symptoms are severe or prolonged

Severe hypoglycemia: Blood glucose below 36 mg/dL or requiring assistance from another person. Risk is highest when combined with sulfonylureas or basal insulin

A Note on Immunogenicity: Antibody Formation

Approximately 70% of patients developed anti-lixisenatide antibodies by Week 24. In 2.4% of patients with the highest antibody concentrations (above 100 nmol/L), reduced glycemic response was observed. These patients also had higher rates of allergic reactions and injection site reactions. If you noticed worsening blood sugar control or increasing injection site reactions on Adlyxin, antibody development may have been a contributing factor.

How Do Side Effects Compare with GLP-1 Alternatives?

All GLP-1 receptor agonists share the core GI side effect profile (nausea, vomiting, diarrhea) because they work through similar mechanisms. Lixisenatide's particularly potent gastric emptying inhibition made it somewhat more likely to cause nausea and vomiting than long-acting agents like semaglutide or dulaglutide, which have less pronounced effects on gastric emptying. Weekly agents may cause initial nausea but often with less intensity per dose due to slower, sustained drug levels.

Tips for Managing GI Side Effects with GLP-1 Medications

Eat smaller, lower-fat meals around the time of injection

Avoid carbonated beverages and high-fat foods during the first weeks of therapy

Stay well hydrated — dehydration can worsen nausea and increase kidney risk

Do not increase dose faster than recommended — follow your titration schedule carefully

For more information, see our guides on Adlyxin drug interactions and the best Adlyxin alternatives in 2026.