Tiredness on Ozempic, Wegovy, Mounjaro and Zepbound: all four labels list fatigue
Fatigue is listed on all four labels, and the two weight-loss labels measure it against placebo: 11% of adults on Wegovy 2.4 mg reported it, against 5% on placebo, and 5 to 7% on Zepbound, against 3%. The Ozempic label names fatigue without a rate, and Mounjaro gives one figure, 10%, from a heart-outcomes trial that had no placebo arm.
Reviewed by Ellis Brandt. Sources checked September 2026.
This guide draws on the cited FDA-approved prescribing information and other FDA sources. It is not medical advice; discuss treatment with your clinician. See the medical disclaimer.
Fatigue on each label
Each figure below carries the trial it came from and what the label counted as fatigue, because the four don’t count the same thing.
Drag the table sideways to read the remaining columns.
| Label | On the drug | Comparison arm | What the row counts | Who was studied |
|---|---|---|---|---|
| Ozempic | Named among reactions above 0.4%, no exact rate | No figure given | Not defined on the label | Adults with type 2 diabetes |
| Wegovy 2.4 mg | 11% (N=2,116) | Placebo 5% (N=1,261) | Fatigue and asthenia | Adults with obesity or overweight, 3 trials of up to 68 weeks |
| Wegovy 7.2 mg | 11% (N=1,311) | Placebo 5% (N=303); Wegovy 2.4 mg 9% (N=304) | Fatigue and asthenia | Adults with obesity, 2 trials of 72 weeks |
| Mounjaro | 10% (6,647 adults exposed) | Dulaglutide 1.5 mg, with no rate given for that arm | Not defined on the label | Adults with type 2 diabetes and established cardiovascular disease, SURPASS-CVOT |
| Zepbound | 5% on 5 mg (N=630), 6% on 10 mg (N=948), 7% on 15 mg (N=941) | Placebo 3% (N=958) | Asthenia, fatigue, lethargy and malaise | Adults with obesity or overweight, Study 1 and Study 2, up to 72 weeks |
Zepbound’s row gathers four terms and Wegovy’s two, in different trials, so the two rates can’t be set against each other. The labels themselves say that rates from one drug’s trials “cannot be directly compared” with another’s. The stomach side effects are set out the same way, each with its own trials, on side effect rates, label by label.
Wegovy
In three trials of up to 68 weeks, 11% of adults on Wegovy 2.4 mg reported fatigue, against 5% on placebo. Only headache and five stomach-related reactions were reported more often on Wegovy in that table. The Medication Guide puts “tiredness (fatigue)” on its list of the most common side effects.
The 7.2 mg dose was tested in two 72-week trials against both placebo and 2.4 mg. Fatigue went up with the dose: 5% on placebo, 9% on 2.4 mg and 11% on 7.2 mg.
Percent of patients in each arm of Study 8 and Study 9, where fatigue includes asthenia. The track is 100% of the arm, so the unfilled part is everyone who reported none.
Wegovy prescribing information, section 6.1, Table 4: three arms of the same two trials. Label version 19, effective 2026-06-18, read September 2026.
The trial in patients aged 12 and older lists reactions seen in at least 3% and more often than on placebo, and fatigue isn’t among them. The 25 mg tablet has no fatigue figure of its own; per the label, the common reactions in its trial were “similar to those listed in Table 3”.
Zepbound
Zepbound’s pooled table puts fatigue at 5% on 5 mg, 6% on 10 mg and 7% on 15 mg, against 3% on placebo, in two trials of up to 72 weeks. Each dose step adds a point.
Its row counts four terms: asthenia, fatigue, lethargy and malaise. In the Medication Guide the same entry reads “feeling tired”, one of the most common side effects it lists. Two trials in adults with obstructive sleep apnea reported adverse reactions similar to the weight trials, with no separate fatigue figure.
Ozempic and Mounjaro
Ozempic’s label lists fatigue under “Other adverse reactions with a frequency of >0.4%”, next to dysgeusia and dizziness. That’s a floor, not a rate: fatigue was reported by more than 0.4% of patients, and the label says no more than that. It isn’t on the Medication Guide’s list of the most common side effects.
Mounjaro’s placebo-controlled table lists reactions seen in at least 5% of patients and more often than on placebo, and it has no fatigue row. The one Mounjaro figure comes from SURPASS-CVOT, a heart-outcomes trial in adults with type 2 diabetes and established cardiovascular disease: among 6,647 exposed to Mounjaro, 10% reported fatigue. That trial compared Mounjaro with dulaglutide, another GLP-1 drug, rather than placebo, and the label doesn’t give dulaglutide’s fatigue rate. So 10% says how often fatigue came up, not how much of it the drug caused.
Drowsiness and weakness on the warning lists
All four Medication Guides list “confusion or drowsiness” and “weakness” among the signs of low blood sugar, alongside shakiness, sweating, hunger and a fast heartbeat. Three of them tie the higher risk to taking the drug with another medicine that lowers blood sugar. Ozempic’s reads: “Your risk for getting low blood sugar may be higher if you use OZEMPIC with another medicine that can cause low blood sugar, such as a sulfonylurea or insulin.” Wegovy’s places the risk in patients with type 2 diabetes, especially those also taking insulin or a sulfonylurea.
That’s a separate entry from fatigue, and none of the four labels links the two. Which diabetes medicines each label flags is set out in the drug interactions page. Hair loss, the other side effect people ask about that isn’t a stomach complaint, sits in the same weight-label tables.
Sources
Drag the table sideways to read the remaining columns.
| Label | Applicant on the label | SPL version | Label effective date | Where it was read |
|---|---|---|---|---|
| Ozempic (semaglutide) | Novo Nordisk Pharmaceutical Industries, LP | 20 | 2026-06-01 | DailyMed, set id adec4fd2-6858-4c99-91d4-531f5f2a2d79 |
| Wegovy (semaglutide) | Novo Nordisk Pharmaceutical Industries, LP | 19 | 2026-06-18 | DailyMed, set id ee06186f-2aa3-4990-a760-757579d8f77b |
| Mounjaro (tirzepatide) | Eli Lilly and Company | 40 | 2026-08-27 | DailyMed, set id d2d7da5d-ad07-4228-955f-cf7e355c8cc0 |
| Zepbound (tirzepatide) | Eli Lilly and Company | 40 | 2026-08-28 | DailyMed, set id 487cd7e7-434c-4925-99fa-aa80b1cc776b |
The rates are from section 6.1 of each label; the low-blood-sugar signs are from each Medication Guide. Every figure and quotation comes from the label’s own tables and text. Each label is the FDA-approved version that was current when it was read in September 2026, identified in the table by its version number and effective date.
See the providers
Fatigue is a property of the drug, not the seller. The boards list who sells each molecule and what each one publishes.
- Semaglutide providersprovider board
Compare semaglutide plans, pharmacy details and cancellation terms.
- Tirzepatide providersprovider board
Compare tirzepatide plans, pharmacy details and cancellation terms.
More, read from the same labels
- First-year GLP-1 costsresearch guide
A low monthly headline does not tell you what a year of treatment will cost. Compare the same medication and service package, then separate the total you expect to spend from the amount you must pay before treatment begins.
- Cancellation and refundsresearch guide
Canceling future membership charges, stopping an upcoming medication order and requesting a refund are three different requests. Get a written answer for each one that applies to you.
- Insurance denial documentsresearch guide
The next step depends on why coverage was denied. A missing document, a formulary restriction and an excluded benefit are different problems. Start with the written decision before paying someone to submit another request.
- Savings and cash-pay eligibilityresearch guide
A manufacturer savings card and a self-pay offer can have different eligibility rules, even for the same medicine. Match the offer to your coverage and exact product before using its advertised price in your budget.
- Verify your GLP-1 pharmacyresearch guide
The website taking your payment, the clinician prescribing and the pharmacy dispensing may be different businesses. Identify each one. A recognizable brand or a reassuring badge does not tell you who will fill the prescription.
- Changing GLP-1 providersresearch guide
Before ending your current service, establish what the new practice needs, what it will charge and when it can evaluate you. Transferring your records does not guarantee that another clinician will continue the same prescription.
- Weight regain after stoppingresearch guide
Weight regain occurred after treatment withdrawal in studies of semaglutide and tirzepatide. The findings support planning follow-up and affordability before an interruption, but they do not predict exactly what will happen to one person.
- Semaglutide vs tirzepatideresearch guide
What the four FDA-approved labels say each molecule is, what each is approved to treat, and where the two differ.
- How they workresearch guide
The receptor each molecule switches on, what the labels say that does to appetite, blood sugar and the stomach, and why one dose lasts a week.
- Is Ozempic insulin?research guide
What the Ozempic label calls semaglutide, how that differs from insulin, and where insulin appears on these labels as a separate medicine.
- Zepbound vs Ozempicresearch guide
Four brand names, two molecules and two kinds of approval: which of these products are the same drug, and what each one is actually approved to do.
- Dose escalation schedulesresearch guide
The starting dose, the escalation interval and the maximum dose each label sets, and why they are not interchangeable.
- Side effect ratesresearch guide
What each label reports for nausea, vomiting, diarrhea and constipation — and the sentence every label prints above those numbers.
- Hair lossresearch guide
Which labels report hair loss, the rate against placebo where a trial measured it, and why two of them put no number on it.
- Missed dose rulesresearch guide
The window each label gives for a late dose, and the minimum gap it requires when the injection day changes.
- Drug interactionsresearch guide
Insulin and sulfonylureas, oral medications, and the oral-contraceptive precaution that appears on two of these four labels and not the other two.
- Buying one onlineresearch guide
The agency's own warning signs for a telehealth GLP-1 seller, its 28-day vial rule, and what it says about drugs that arrive warm.
- Zepbound by doseresearch guide
What each Zepbound dose achieved in the trials printed in its label, what the label says about choosing a maintenance dose, and what the higher doses cost in side effects.
- Zepbound at 3 monthsresearch guide
What does the Zepbound label report about three-month weight loss and maintenance dosing?
- Injecting tirzepatideresearch guide
The injection sites, the rotation rule and the steps for the single-dose pen, the KwikPen and the vial and syringe, exactly as the FDA-approved Instructions for Use give them.
- Refrigeration and storageresearch guide
How cold each pen is kept, how many days it can spend at room temperature, and what the labels say about heat and freezing.
- Who should not take oneresearch guide
The boxed warning every one of these labels carries, the two contraindications, and which warnings appear on which product.
What each fatigue row counts
Ozempic: not defined on the label
Wegovy: fatigue and asthenia
Mounjaro: not defined on the label
Zepbound: asthenia, fatigue, lethargy and malaise
Section 6.1 of each label. The rows count different things, one more reason the rates don’t compare.