Does Tirzepatide Make You Tired? Fatigue in the Trials
Does tirzepatide make you tired? It can: fatigue is one of the most common side effects on the Zepbound label. In the label's weight trials, it was reported by 5% to 7% of people on the drug, against 3% on placebo.
If you feel more tired or run down since starting tirzepatide, that matches a side effect the label lists. Most people in the trials did not report it, and the label says to talk to your healthcare provider if it bothers you or does not go away.
Short answer
- What you may be noticing
- Tiredness, weakness, low energy or feeling unwell. The Zepbound label groups asthenia (weakness), fatigue, lethargy and malaise together as fatigue.
- How common it is, by the label
- In the Zepbound label's weight trials, 5% to 7% of people on the drug reported fatigue, against 3% on placebo.
- What the label says to do
- The Medication Guide says to talk to your healthcare provider about any side effect that bothers you or does not go away.
- When it may be something else
- The Medication Guide lists drowsiness and weakness among signs of low blood sugar, and says that risk may be higher with insulin or a sulfonylurea.
Fatigue on the Zepbound label
Yes. The Zepbound label lists fatigue among its most common side effects, reported in at least 5% of patients.
The Medication Guide, the leaflet written for patients, lists feeling tired in its list of side effects. In the label, the word fatigue covers four reported terms: weakness (asthenia), fatigue, lethargy and malaise.
How common is fatigue on tirzepatide?
In the Zepbound label's weight trials, fatigue was reported by 5% to 7% of people on the drug and 3% on placebo. It rose a little with each dose but stayed below 1 in 10.
The Zepbound label's side effect table for its weight trials lists fatigue in:
- Placebo: 3%
- Zepbound 5 mg: 5%
- Zepbound 10 mg: 6%
- Zepbound 15 mg: 7%
Disclaimer: these are trial doses, not a recommendation. Dose decisions belong with a licensed clinician.
Fatigue rates in the label and the SURMOUNT-3 trial
In the Zepbound label trials and in SURMOUNT-3, fatigue was more common on tirzepatide than on placebo. The table puts every figure in one place.
| Source | Group | Fatigue reported |
|---|---|---|
| Zepbound label, weight trials | Placebo | 3% |
| Zepbound label, weight trials | Zepbound 5 mg / 10 mg / 15 mg | 5% / 6% / 7% |
| SURMOUNT-3 results, ClinicalTrials.gov | Placebo | 9 of 292 people |
| SURMOUNT-3 results, ClinicalTrials.gov | Tirzepatide | 20 of 287 people |
| Mounjaro label, heart outcomes trial in type 2 diabetes | Mounjaro | 10% |
SURMOUNT-3 was a trial of tirzepatide after a lifestyle weight loss program. The heart outcomes trial was in adults with type 2 diabetes and had no placebo figure in this table.
Disclaimer: these are trial doses, not a recommendation. Dose decisions belong with a licensed clinician.
Sources: Zepbound FDA label and Medication Guide; SURMOUNT-3 results, ClinicalTrials.gov; Mounjaro FDA label
Does Mounjaro make you tired too?
Yes: the US Mounjaro label reports fatigue in 10% of people in one heart outcomes trial, and the EU leaflet lists feeling tired. Mounjaro is the same medicine as Zepbound.
That US label trial was in adults with type 2 diabetes and heart disease. The EU leaflet lists feeling tired in people treated for type 2 diabetes and for weight management. For how the two brands compare, see is Zepbound the same as Mounjaro.
Sources: Mounjaro FDA label; Mounjaro EU product information (EMA)
Why might tirzepatide make you tired?
No label or study we found states a cause. The Zepbound label lists fatigue as something people reported, not why it happened.
The label does name a few other things that can come with feeling tired. We list them here so they are not missed. The sources do not say they explain the fatigue.
Low blood sugar
The Zepbound Medication Guide lists drowsiness and weakness among the signs of low blood sugar. It says the risk may be higher when Zepbound is used with medicines that can cause low blood sugar, such as insulin or a sulfonylurea.
Fluid loss
The Medication Guide says diarrhea, nausea and vomiting may cause a loss of fluids, called dehydration, which may cause kidney problems. It says drinking fluids helps reduce the chance of dehydration.
Eating less
The label says tirzepatide decreases calorie intake. It also says the drug lowers body weight with more fat loss than lean mass loss.
A 2026 BMJ analysis compared obesity drugs. It found tirzepatide reduced fat mass the most, by 25.7%, but also lean mass the most, by 8.3%. Our sources do not link this to tiredness.
Sources: Zepbound FDA label and Medication Guide; BMJ 2026, network meta-analysis of obesity drugs
How long does tirzepatide make you feel tired?
No label gives a time frame for tirzepatide fatigue. One observational study saw it become less common over time.
That 2025 study looked back at a 12-month remote weight program using semaglutide and tirzepatide. It reported that common early side effects, including constipation, nausea and fatigue, showed significant reductions. That study only observed people in a program. It was not a controlled trial.
Why does Ozempic make you tired?
The Ozempic label lists fatigue as a side effect but, like the tirzepatide labels, gives no reason for it. Ozempic and Wegovy both contain semaglutide, a different drug from tirzepatide.
The Ozempic label lists fatigue, a change in taste and dizziness among other reactions seen in more than 0.4% of people. Our sources for this page did not include the Wegovy label, so we do not give a Wegovy tiredness figure.
A 2026 BMJ analysis of obesity drugs found that fatigue risk rose most with three other drugs: naltrexone-bupropion, orforglipron and CagriSema. For a wider look, see our GLP-1 side effects guide.
Sources: Ozempic FDA label; BMJ 2026, network meta-analysis of obesity drugs
What the label says to do about tiredness
The Zepbound label gives one general line: the Medication Guide says to talk to your healthcare provider about any side effect that bothers you or does not go away.
It does not give a plan for dealing with fatigue. Questions about how to manage it belong with the prescriber. Other common side effects are covered in tirzepatide diarrhea and does tirzepatide cause hair loss. Doses and injection sites are in the tirzepatide dosage guide.
What the evidence does not show about tirzepatide and fatigue
Three common claims about tiredness on tirzepatide have no primary source behind them. Here is what we could not confirm.
Why tirzepatide causes tiredness
No label or study we found states a cause. The label only lists fatigue as a reported reaction.
How long tirzepatide fatigue lasts
There is no official figure. One observational study saw fatigue become less common over time, but that is not a trial result.
Fatigue on retatrutide
Our sources had no fatigue data for retatrutide, so this page does not answer whether reta makes you tired.
Sources: Zepbound FDA label and Medication Guide; JMIR Form Res 2025, remote weight program study
Tirzepatide tiredness questions
Does tirzepatide make you tired?+
It can. The Zepbound label lists fatigue among its most common side effects, reported in at least 5% of patients, and the Medication Guide lists feeling tired. In the label weight trials, fatigue was reported by 3% on placebo and by 5%, 6% and 7% on the 5 mg, 10 mg and 15 mg doses. Disclaimer: these are trial doses, not a recommendation. Dose decisions belong with a licensed clinician.
Is it normal to feel exhausted while taking Zepbound?+
Fatigue is a known, listed side effect. The label groups weakness (asthenia), fatigue, lethargy and malaise together under fatigue. The Medication Guide says to talk to your healthcare provider about any side effect that bothers you or does not go away.
How long does tirzepatide make you feel tired?+
There is no official figure. A 2025 observational study of a 12-month remote weight program reported that common early side effects, including fatigue, showed significant reductions. That is one observational study, not a trial result.
Can Ozempic make you tired?+
The Ozempic label lists fatigue among other adverse reactions seen at a frequency above 0.4%. Ozempic contains semaglutide, a different drug from tirzepatide.
Does Mounjaro cause fatigue?+
Mounjaro is tirzepatide too. In a heart outcomes trial in adults with type 2 diabetes described in the US label, fatigue was reported by 10% of people on Mounjaro. The EU leaflet lists feeling tired in people treated for type 2 diabetes and for weight management.
How do you deal with fatigue from GLP-1 drugs?+
The labels do not give a plan. The Zepbound Medication Guide says to talk to your healthcare provider about any side effect that bothers you or does not go away. Questions about managing tiredness belong with the prescriber.
Why does tirzepatide make you tired?+
No label or study we found states a cause. The label does list related things: signs of low blood sugar include drowsiness and weakness, diarrhea and vomiting can cause fluid loss, and the drug lowers calorie intake. The sources do not say these explain the fatigue.
Sources: Zepbound FDA label and Medication Guide; Mounjaro FDA label; Mounjaro EU product information (EMA); Ozempic FDA label; JMIR Form Res 2025, remote weight program study
Related tirzepatide guides
This guide is for educational purposes only and is not medical advice. It describes what drug labels and published studies report about tirzepatide and fatigue. Questions about your own symptoms or medicine belong with a licensed clinician.