# Feeling tired on a GLP-1

> All four list it, and both NHS pages name feeling tired among common side effects. Wegovy’s leaflet calls feeling weak or tired very common, and says it usually goes away over time; Ozempic’s calls tiredness common. In two Zepbound trials, 5% to 7% reported fatigue, against 3% on placebo.

Canonical: https://jabwise.app/guides/feeling-tired. Sources checked 12 October 2026. General information, not medical advice: follow your prescriber.

## How common it is

From each leaflet and Zepbound’s label, quoted as written. Mounjaro’s gives a different answer for its heart study of people with type 2 diabetes.

- **Mounjaro**: Listed as: "Feeling tired (fatigue)" ([Mounjaro KwikPen patient leaflet](https://www.medicines.org.uk/emc/product/15481/pil)); How common: "Fatigue was very common in the type 2 diabetes cardiovascular disease study and common in patients treated for weight management, and type 2 diabetes." ([Mounjaro KwikPen patient leaflet](https://www.medicines.org.uk/emc/product/15481/pil))
- **Zepbound**: Listed as: "feeling tired" ([Zepbound prescribing information](https://uspl.lilly.com/zepbound/zepbound.html)); How common: "The most common adverse reactions, reported in ≥5% of patients treated with ZEPBOUND" ([Zepbound prescribing information](https://uspl.lilly.com/zepbound/zepbound.html))
- **Wegovy**: Listed as: "feeling weak or tired" ([Wegovy FlexTouch patient leaflet](https://www.medicines.org.uk/emc/product/13800/pil)); How common: "Very common: may affect more than 1 in 10 people" ([Wegovy FlexTouch patient leaflet](https://www.medicines.org.uk/emc/product/13800/pil))
- **Ozempic**: Listed as: "Tiredness" ([Ozempic patient leaflet](https://www.medicines.org.uk/emc/product/9748/pil)); How common: "Common (may affect up to 1 in 10 people)" ([Ozempic patient leaflet](https://www.medicines.org.uk/emc/product/9748/pil))

## What else they say

- **It often eases**: Wegovy’s leaflet lists feeling weak or tired with its very common side effects, and says these usually go away over time.
- **In Zepbound’s trials**: Fatigue, counting weakness and lethargy, was reported by 5% to 7% of people on Zepbound, against 3% on placebo.
- **Low blood sugar signs**: Mounjaro’s leaflet lists drowsiness and weakness among signs of low blood sugar, likelier with insulin or a sulphonylurea.
- **If it bothers you**: If a side effect bothers you or doesn’t go away, the NHS says a pharmacist or doctor may give advice on how to reduce it.

## Questions

### Does Mounjaro make you tired?

Its leaflet lists feeling tired (fatigue): very common in a heart study of people with type 2 diabetes, and common in people treated for weight management or type 2 diabetes.

### Does the tiredness go away?

Wegovy’s leaflet says its very common side effects, feeling weak or tired among them, usually go away over time. The other leaflets don’t say so for tiredness.

### Could it be low blood sugar?

Mounjaro’s leaflet lists drowsiness and weakness among the symptoms of low blood sugar, and Wegovy’s lists feeling sleepy or weak, for people with diabetes. Mounjaro’s says your doctor should tell you how to treat it.

## In Jabwise: Check-ins

Jabwise notes your energy through the day. Mood, food noise and energy on three sliders, morning, afternoon and evening, then a tap for any side effects. Progress shows how each changes over time.

## Getting real advice

- **A pharmacist, your doctor or NHS 111**: If you’re not sure how to use your medicine, or a side effect bothers you or won’t go away. NHS 111 if you think you might be having serious side effects, or you’ve used too much. [NHS: Semaglutide](https://www.nhs.uk/medicines/semaglutide/), [NHS: Tirzepatide](https://www.nhs.uk/medicines/tirzepatide/), [NHS 111 online](https://111.nhs.uk/)
- **Report a side effect**: Anyone can, not only doctors. [Yellow Card (UK)](https://yellowcard.mhra.gov.uk/), [MedWatch (US)](https://www.fda.gov/safety/medwatch-fda-safety-information-and-adverse-event-reporting-program)

## Sources

- [Mounjaro KwikPen patient leaflet](https://www.medicines.org.uk/emc/product/15481/pil)
- [Zepbound prescribing information](https://uspl.lilly.com/zepbound/zepbound.html)
- [Wegovy FlexTouch patient leaflet](https://www.medicines.org.uk/emc/product/13800/pil)
- [Ozempic patient leaflet](https://www.medicines.org.uk/emc/product/9748/pil)
- [NHS: Tirzepatide](https://www.nhs.uk/medicines/tirzepatide/)
- [NHS: Semaglutide](https://www.nhs.uk/medicines/semaglutide/)