The short answer
Yes, GLP-1 medicines can make you tired. Fatigue is a listed side effect for Wegovy, Zepbound, and Foundayo. On Wegovy, 11% of people felt tired or weak, compared with 5% on placebo.1
Much of the tiredness comes from what changes around the medicine: eating less, drinking less, stomach side effects, broken sleep, and doing too much too fast. The labels do not say how long it lasts. If it does not ease on a steady dose, talk to your prescriber.
"I feel wiped out"
One of my friends felt completely wiped out on a GLP-1. When we talked, it was clear it could be a number of things. She was not eating the same, so she was not getting the nutrition, and without nutrition you do not get the energy. She was probably not drinking as much. And she wanted to feel better, so she was pushing hard at the gym.
That combination burns people out. They are off their regular routine of getting enough rest and enough nutrition to balance their body.
Is fatigue a side effect of GLP-1s?
Yes. Here is what the official labels report. Ozempic is the same medicine as Wegovy, and Mounjaro is the same medicine as Zepbound.
| Medicine | Tired or weak | Placebo |
|---|---|---|
| Wegovy (Ozempic) | 11% | 5% |
| Zepbound (Mounjaro) | 5% to 7% | 3% |
| Foundayo (daily pill) | 6% to 9% | 4% |
For Zepbound and Foundayo, fatigue was more common at higher doses.2,3 These numbers come from weight loss trials.
The GLP-1 fatigue loop
Tiredness on these medicines often feeds itself. Here is the pattern I see:
Then the loop starts again.
Six reasons a GLP-1 can wear you out
Reason 1
You are not getting enough nutrition
When you eat much less, some nutrients can run low. Experts list iron, calcium, magnesium, zinc, B12, and vitamin D, among others. Fatigue that is worse than expected can be a sign of a deficiency.4
What to try: make each meal count, with protein, fruit, vegetables, and whole grains. Ask your doctor if you need blood tests.
Reason 2
You are not drinking enough
Many people feel less thirsty. Vomiting and diarrhea can also drain fluids. The Wegovy label warns that fluid loss from these side effects has led to kidney problems in some people.1
What to try: sip water through the day, and call your doctor if you cannot keep fluids down.
Reason 3
Protein: too little, or too much
Protein helps protect muscle while you lose weight. A 2025 expert advisory suggests about 80 to 120 grams a day for most adults, and advises against very high amounts over a long time.4
Sometimes people go the other way and eat too much protein, and that can be a problem too. You have to take life with moderation. Moderation with just about everything.
What to try: spread protein across your meals, and ask a dietitian what amount fits you.
Reason 4
Stomach side effects at night
Nausea, vomiting, diarrhea, and reflux can wake you up and break up your sleep. On Wegovy, these side effects increased during dose increases.1
What to try: eat smaller meals every 3 to 4 hours, skip large or fatty meals, and limit alcohol, which can make nausea and reflux worse.4
Reason 5
Doing too much, too fast
Strength training matters on a GLP-1, because it helps protect muscle.4 But going from zero to daily hard workouts while you eat less is a fast way to burn out.
What to try: build up slowly, and keep rest days.
Reason 6
A recent dose increase
Side effects often rise when the dose goes up.1,3 If you feel worse after an increase, tell your prescriber. Do not change your dose on your own.
Does GLP-1 fatigue go away?
The labels do not say how long fatigue lasts. Stomach side effects are known to rise during dose increases.1 If you are tired for more than a few weeks on the same dose, or it is getting worse, talk to your prescriber. Blood tests, a slower dose increase, or changes to your eating may help.
A daily rhythm that supports your energy
This is the routine I suggest to friends:
Ask your pharmacist before adding melatonin or any supplement to a GLP-1. For more, read GLP-1s and sleep, tired but cannot sleep, and how much melatonin should I take. Taking more is not better, so also read how much melatonin is too much.
When tiredness is a warning sign
Call your doctor if
- You cannot keep fluids down, or you feel dizzy when you stand up.
- Your heart races while you are resting. Heart rate can rise on these medicines.1
- You wake up sweaty or shaky, especially if you take insulin or a sulfonylurea.1,2
- You are exhausted for weeks, even with good food, fluids, and sleep.
- You feel low, hopeless, or not yourself. The labels tell doctors to watch for new or worse depression.1 If you have thoughts of harming yourself, call or text 988 right away (US).
Where Driffly fits
A low dose for a steady bedtime
Driffly is not made for GLP-1 medicines and has not been studied with them. But if you and your pharmacist decide melatonin fits your bedtime routine, a low dose is where I would start, so it does not add to your fatigue the next day. That is why I chose 1 mg of melatonin for Driffly, with valerian root, lavender, chamomile, and hibiscus to support a calm wind down.*
- 1 mg of melatonin, the same in every strip.
- Melts on your tongue. No water and no sugar.
- Take it 30 minutes before bed, at the same time every night.
Every order comes with a 30 night money back guarantee.
Common questions about GLP-1 fatigue
Does Wegovy fatigue go away?
The label does not say how long it lasts. Side effects often rise with dose increases.1 If you are still tired after a few weeks on the same dose, talk to your prescriber.
Why does Ozempic make me tired?
Fatigue is a listed side effect of semaglutide, the medicine in Ozempic and Wegovy.1 Eating and drinking less, stomach side effects, and poor sleep can add to it.
Why am I so tired on Mounjaro or Zepbound?
Fatigue is listed on the Zepbound label, and it was more common at higher doses.2 Mounjaro is the same medicine. Check your food, fluids, sleep, and recent dose changes.
Is fatigue worse after a dose increase?
It can be. On Wegovy, stomach side effects increased during dose increases, and on Zepbound and Foundayo, fatigue was more common at higher doses.1,2,3
What helps GLP-1 fatigue?
Regular meals with enough protein, plenty of fluids, steady exercise, and a regular bedtime. If it lasts, ask your doctor about blood tests.4
Is there a supplement for GLP-1 fatigue?
No supplement is proven to fix GLP-1 fatigue. Experts say vitamin D, calcium, B12, or a multivitamin may be considered, ideally guided by blood tests and your doctor.4
Why am I tired but cannot sleep on Zepbound?
Night time nausea, reflux, hunger, or a changed routine can break up sleep while fatigue builds during the day. Read GLP-1s and sleep for a full checklist.
Sources
- Wegovy (semaglutide) injection, prescribing information. US Food and Drug Administration label, 2024.
- Zepbound (tirzepatide) injection, prescribing information. US Food and Drug Administration label, 2026.
- Foundayo (orforglipron) tablets, US prescribing information. 2026.
- Mozaffarian D, et al. Nutritional priorities to support GLP-1 therapy for obesity: a joint advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. Obesity. 2025;33(8):1475-1503.
Tyler Smith, RN, BSN, BA is a registered nurse and the founder of Driffly. He writes and reviews the articles in the sleep education hub. About Tyler
The author is the founder of Driffly, which sells the product mentioned in this article. Driffly does not sell GLP-1 medicines or any prescription medicine. This article is for education and is not medical advice. Do not stop or change any medicine without talking to your doctor. *These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.