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Wegovy · Side effects

Wegovy side effects

How often each side effect showed up on Wegovy vs placebo in the trials behind the FDA label.

Clinician review pending Updated

How common each one is

Nauseaplacebo 16%
44.0%
Diarrheaplacebo 16%
30.0%
Vomitingplacebo 6%
24.0%
Constipationplacebo 11%
24.0%
Stomach painplacebo 10%
20.0%
Headacheplacebo 10%
14.0%
Fatigueplacebo 5%
11.0%
Dizzinessplacebo 4%
8.0%
Bloatingplacebo 5%
7.0%
Burpingplacebo under 1%
7.0%
Gasplacebo 4%
6.0%
Low blood sugarplacebo 2%
6.0%
Hair lossplacebo 1%
3.0%
Highest rate across label doses. Placebo-controlled weight-management trials in the Wegovy label (2.4 mg).

Label rates vs placebo

Side effectWegovyPlacebo
Nausea44%16%
Diarrhea30%16%
Vomiting24%6%
Constipation24%11%
Stomach pain20%10%
Headache14%10%
Fatigue11%5%
Heartburn and indigestion9%3%
Dizziness8%4%
Bloating7%5%
Burping7%under 1%
Gas6%4%
Low blood sugar6% (people with type 2 diabetes)2%
Hair loss3%1%

When side effects happen

In the trials, stomach side effects were mostly mild to moderate and most common during the dose-increase weeks. They often flare for a few days after each step up, then ease on the same dose.

Serious warnings on the label

  • Pancreatitis. Stop and get care right away for severe stomach pain that won't go away, with or without vomiting, sometimes felt in the back.
  • Gallbladder problems. Gallstones and gallbladder inflammation were more common in trials, especially with rapid weight loss. Watch for upper-right belly pain, fever, yellow skin or eyes, or clay-colored stools.
  • Low blood sugar. Risk rises when combined with insulin or a sulfonylurea. Signs include shakiness, sweating, fast heartbeat, confusion and dizziness.
  • Kidney problems. Vomiting and diarrhea can cause dehydration, which can worsen kidney function. Drink fluids and call your prescriber if you can't keep them down.
  • Serious allergic reactions. Get emergency help for swelling of the face, lips, tongue or throat, trouble breathing or a severe rash.
  • Severe stomach problems. Not recommended if you already have severe gastroparesis (very slow stomach emptying).
  • Aspiration during anesthesia. Tell your care team you take a GLP-1 medicine before any surgery or procedure that uses anesthesia or deep sedation, because food can stay in the stomach longer.
Boxed warningRisk of thyroid C-cell tumors. In rodent studies these medicines caused thyroid C-cell tumors. It isn't known whether they cause them in people, including medullary thyroid carcinoma (MTC). Don't use them if you or a family member has had MTC, or if you have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).

Common questions

What is the most common side effect of Wegovy?

Nausea, reported in 44% of people vs 16% on placebo.

How long do Wegovy side effects last?

Stomach side effects are most common in the weeks after starting and after each dose increase, and usually ease over days to weeks on the same dose. Tell your prescriber if they don't.

Which Wegovy side effects are serious?

Severe stomach pain that won't go away, signs of pancreatitis or gallbladder problems, severe allergic reactions, dehydration and kidney problems, and a lump in the neck. Get care right away for these.

Sources

  1. Wegovy prescribing information (FDA label on DailyMed)
  2. STEP 1 trial publication

Clinician review pending. Drafted from primary sources and waiting for sign-off by a licensed clinician (MD, DO or PharmD) before launch. Every number is checked against its source. Drug facts are re-checked quarterly, prices monthly and whenever a label changes. How we review · Report an error