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Label + trial reference

GLP-1 side effects compared

A structured view of common adverse reactions from prescribing labels and published trial data, with placebo context preserved for each reported rate.

Last updated: June 2026

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How to read this

Rates are trial context, not predictions

The sheet compares the percent of trial participants reporting selected side effects. Each entry keeps the placebo comparison next to the active-drug rate where available.

Do not use these figures to choose or avoid a medication without medical advice. Your history, dose escalation, and indication matter.

1

GI events are the most consistently reported effects across GLP-1 medicines in this sheet.

2

Placebo arms, trial populations, duration, and reporting thresholds differ, so rates are not clean head-to-head comparisons.

3

N/A means not reported at the label's inclusion threshold or not available from the cited pivotal table — not zero risk.

Comparison table

Common effects by medicine and dose

Figures marked with ~ are approximate published trial figures rather than FDA-label table values.

GLP-1 side effect rates by medicine and dose
Side effectOzempic®0.5 mgsemaglutideOzempic1 mgsemaglutideWegovy®2.4 mgsemaglutideZepbound®5 mgtirzepatideZepbound10 mgtirzepatideZepbound15 mgtirzepatideMounjaro®5 mgtirzepatideMounjaro10 mgtirzepatideMounjaro15 mgtirzepatideSaxenda®3 mgliraglutideFoundayo®36 mgorforglipron
Nausea15.8%vs 6.1% placebo20.3%vs 6.1% placebo44%vs 16% placebo25%vs 8% placebo29%vs 8% placebo28%vs 8% placebo12%vs 4% placebo15%vs 4% placebo18%vs 4% placebo39.3%vs 13.8% placebo~33.7%vs 10.4% placebo
Diarrhea8.5%vs 1.9% placebo8.8%vs 1.9% placebo30%vs 16% placebo19%vs 8% placebo21%vs 8% placebo23%vs 8% placebo12%vs 9% placebo13%vs 9% placebo17%vs 9% placebo20.9%vs 9.9% placebo~23.1%vs 9.6% placebo
Vomiting5%vs 2.3% placebo9.2%vs 2.3% placebo24%vs 6% placebo8%vs 2% placebo11%vs 2% placebo13%vs 2% placebo5%vs 2% placebo5%vs 2% placebo9%vs 2% placebo15.7%vs 3.9% placebo~24.0%vs 3.5% placebo
Constipation5%vs 1.5% placebo3.1%vs 1.5% placebo24%vs 11% placebo17%vs 5% placebo14%vs 5% placebo11%vs 5% placebo6%vs 1% placebo6%vs 1% placebo7%vs 1% placebo19.4%vs 8.5% placebo~25.4%vs 9.3% placebo
HeadacheN/AN/A14%vs 10% placeboN/AN/AN/AN/AN/AN/A13.6%vs 12.6% placebo~9%vs 7% placebo
Fatigue / astheniaN/AN/A11%vs 5% placebo5%vs 3% placebo6%vs 3% placebo7%vs 3% placeboN/AN/AN/A7.5%vs 4.6% placebo~9%vs 4% placebo
Medication notes

Why direct comparisons are limited

The numbers in the table above come from different labels, pooled trials, indications, and inclusion thresholds.

Ozempic (semaglutide)

FDA Prescribing Label Table 1, revised 10/2025. Pool of two placebo-controlled type 2 diabetes trials: SUSTAIN-1 and SUSTAIN-5. Ozempic is not approved for obesity, so these figures should not be compared directly to obesity-trial figures.

Wegovy (semaglutide 2.4 mg)

FDA Prescribing Label Table 5, revised 07/2023. Pool of three randomized, double-blind, placebo-controlled trials: STEP 1, STEP 2, and STEP 3.

Zepbound (tirzepatide)

FDA Prescribing Label Table 1, revised 2026. Pool of two placebo-controlled weight-reduction trials: SURMOUNT-1 and SURMOUNT-2.

Mounjaro (tirzepatide)

FDA Prescribing Label Table 1, revised 2025. Pool of two placebo-controlled type 2 diabetes trials: SURPASS-1 and SURPASS-5. Mounjaro is not approved for obesity.

Saxenda (liraglutide 3.0 mg)

FDA Prescribing Label Table 2, revised 10/2025. Pool of five double-blind, placebo-controlled adult SCALE trials with treatment up to 56 weeks.

Foundayo / orforglipron

Approximate figures from published ATTAIN-1 trial reporting for once-daily oral orforglipron 36 mg. These are not FDA label figures.

Primary Sources

These are the source labels and trial attributions used for the side-effect rates above. FDA label citations refer to the prescribing-label tables named in the medication notes.

Foundayo / orforglipron side-effect summary

FindHonestCare Foundayo side-effects page cited in the source sheet

View source
Important context

N/A does not mean no risk

In this reference, N/A means the side effect was not reported at the label's inclusion threshold, or that a dose-specific figure was not available from the cited pivotal table. It should not be interpreted as zero incidence.

Side effects can be dose-related and may change during dose escalation. Talk with a licensed clinician about risks, contraindications, and what to do if symptoms occur.

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