Fatigue on a GLP-1: 11 percent on Wegovy and 7 percent on Zepbound
Fatigue reached 11 percent on Wegovy 2.4 mg and 7 percent on Zepbound 15 mg in the clinical trials printed on their FDA labels, against 5 and 3 percent on placebo. Both labels count lethargy and malaise in the same row. GLP Chart read them on DailyMed, revised June and August 2026.
| Label and dose | Who was in the trial | On the drug | On placebo |
|---|---|---|---|
| Wegovy 2.4 mg (June 2026 label) | adults with obesity or overweight, n=2,116 | 11% | 5% (n=1,261) |
| Wegovy 2.4 mg (June 2026 label) | adults in the trial comparing the two maintenance doses, n=304 | 9% | 5% (n=303) |
| Wegovy 7.2 mg (June 2026 label) | adults in the trial comparing the two maintenance doses, n=1,311 | 11% | 5% (n=303) |
| Zepbound 5 mg (August 2026 label) | adults with obesity or overweight, n=630 | 5% | 3% (n=958) |
| Zepbound 10 mg (August 2026 label) | adults with obesity or overweight, n=948 | 6% | 3% (n=958) |
| Zepbound 15 mg (August 2026 label) | adults with obesity or overweight, n=941 | 7% | 3% (n=958) |
The row is four things, not one
Both weight-management labels footnote the fatigue row the same way. It counts asthenia, fatigue, lethargy and malaise together. So 11 percent is the share of the Wegovy arm that reported any of the four, and a reader who is tired in the afternoons and a reader who feels unwell all week are in the same number.
The placebo columns are 5 percent and 3 percent. Both arms were on a reduced-calorie diet.
Ozempic and Mounjaro do not report it at all
Their tables print reactions reported by at least 5 percent of treated adults, and fatigue did not clear that cut in those clinical trials. The rate fell under the cut. That is all a missing row tells you.
What a slower ladder costs
Neither label says what the slower route costs. On some programs the lower dose is the cheaper one and on others the price does not move at all.
| Drug | Cheapest program we track | At the maintenance dose | At the top dose it publishes |
|---|---|---|---|
| Wegovy | Knownwell | $299 a month | Publishes one figure only |
| Zepbound | CVS MinuteClinic | $428 a month | $528 a month |
LifeMD charges $200 a month more at the top of its ladder than at the dose below it. Holding a step for 4 weeks on that plan saves $200. Ask the program what it charges at each dose before you agree to climb.
Compare every program at its real maintenance price →
Frequently asked questions
How common is fatigue on a GLP-1?
Wegovy's label puts it at 11 percent at 2.4 mg against 5 percent on placebo. Zepbound's puts it at 5 percent at 5 mg, 6 percent at 10 mg and 7 percent at 15 mg, against 3 percent on placebo. It sits well below nausea and diarrhea on both labels.
What does the label mean by fatigue?
More than one thing. Both weight-management labels say the row counts asthenia, fatigue, lethargy and malaise together. One percentage covers all four.
Why is there no fatigue number for Ozempic or Mounjaro?
Because those two tables only print reactions reported by at least 5 percent of treated adults. Fatigue did not clear that cut in the diabetes trials. So the labels carry no row for it.
Does a higher dose make it worse?
Slightly, on both molecules. Zepbound climbs from 5 percent at 5 mg to 7 percent at 15 mg. Wegovy's own high-dose table reads 9 percent at 2.4 mg and 11 percent at 7.2 mg. These are small moves next to nausea, which shifts by several points across the same columns.
Does the label say what to do about it?
Only through the dose. Wegovy's label says to consider delaying escalation for 4 weeks if a dose is not tolerated. Zepbound's says to consider a lower maintenance dosage. Neither label prescribes anything for tiredness itself, and neither should be read as doing so.
Every dosage sentence on this page is written to a prescriber, not to you. Holding a dose, dropping back or stopping changes what the drug is doing. Take the label language to the appointment.
Sources
Evidence checked August 31, 2026
Every figure above is taken from the document beside it, the FDA label or the trial that produced it, so you can read the source instead of trusting us. No clinician reviews these pages. What that means.
- The 11 percent Wegovy figure, the 9 against 11 percent reading at 2.4 mg and 7.2 mg, and the note that the row counts asthenia, fatigue, lethargy and malaiseFDA prescribing information for Wegovy, injection and tablets (DailyMed, revised June 2026)
- The Zepbound rates at 5 mg, 10 mg and 15 mg, the same four-term footnote, and the sentence about considering a lower maintenance dosageFDA prescribing information for Zepbound (DailyMed, revised August 2026)
- The Ozempic adverse-reaction table, which cuts at 5 percent and carries no fatigue rowFDA prescribing information for Ozempic injection (DailyMed, revised June 2026)
- The Mounjaro adverse-reaction table, which cuts at 5 percent and carries no fatigue rowFDA prescribing information for Mounjaro (DailyMed, revised August 2026)
