People starting tirzepatide often ask whether a new headache comes from the drug. The prescribing information gives a short answer, and the trial registry gives a longer one.
This page covers both, plus the labeled problems that can bring on a headache and the small studies in headache disorders. The wider list of reactions is in tirzepatide side effects.
What the labels say
The Zepbound label’s main table lists reactions seen in at least 2% of people on the drug and more often than on placebo, across two weight trials of up to 72 weeks [1]. Headache is not in it.
The Mounjaro label, from its diabetes trials, lists reactions seen in at least 5% of patients [2]. Headache is not there either. In both labels, the word appears in one place: the patient list of low blood sugar symptoms.
What the trial results recorded
Five tirzepatide weight trials have posted their adverse event tables on ClinicalTrials.gov. Each table counts any event that at least 5% of a group reported, so headache shows up in all of them.
| Trial and group | Tirzepatide | Comparator |
|---|---|---|
| SURMOUNT-1, no diabetes, to week 193 | 7.5%, 8.0%, 7.0% (5, 10, 15 mg) | Placebo 7.3% |
| SURMOUNT-2, type 2 diabetes, to week 76 | 5.1%, 4.8% (10, 15 mg) | Placebo 2.9% |
| SURMOUNT-3, after a lifestyle program, to week 76 | 9.4% | Placebo 7.5% |
| SURMOUNT-4, open-label start, weeks 0 to 36 | 7.2% | None, all on the drug |
| SURMOUNT-4, randomized, weeks 36 to 92 | 1.5% | Placebo 3.0% |
| SURMOUNT-5, head-to-head, to week 72 | 7.2% | Semaglutide 7.2% |
In SURMOUNT-1, the largest trial, headache was about as common on placebo as on any dose [3]. Roughly 47 to 51 people per arm of about 640 reported one.
SURMOUNT-2 enrolled people with type 2 diabetes and showed the widest relative gap [4]. Sixteen of 312 people on 10 mg and 15 of 311 on 15 mg reported headache, against 9 of 315 on placebo.
SURMOUNT-3 put the drug about 2 points above placebo [5]. In SURMOUNT-4, people who stayed on tirzepatide after the first 36 weeks reported headache less often than those switched to placebo [6]. In SURMOUNT-5, the rate matched semaglutide exactly [7].
That last point is worth setting beside the semaglutide record. In the Wegovy trials, headache ran a few points above placebo, as covered in semaglutide headache.
Labeled problems that can bring on a headache
The labels do not say tirzepatide causes headaches. They do describe problems in which a headache can be one symptom.
Low blood sugar. Both patient information sections list headache among its signs [1] [2]. In the Zepbound trial of people with type 2 diabetes, low blood sugar occurred in 4.2% on the drug against 1.3% on placebo, and in 10.3% of those also taking a sulfonylurea.
Dehydration. Both labels warn that nausea, vomiting and diarrhea can cause fluid loss, with kidney injury reported afterward [1] [2]. The same warning for semaglutide is covered in does Ozempic cause dehydration.
Low blood pressure. In the pooled Zepbound weight trials, hypotension occurred in 1.6% on the drug against 0.1% on placebo, and dizziness in 4% to 5% against 2% [1]. The label notes that hypotension also appeared alongside stomach upset and dehydration.
What spontaneous reports show
A 2026 analysis of the European Union’s adverse reaction database looked at reports for tirzepatide, semaglutide and liraglutide [8]. Headache made up 2.51% of tirzepatide reports, though it is not listed in tirzepatide’s European product information.
Reports like these are sent in voluntarily. They show what people and clinicians noticed, not how often it happens, and the authors ask for cautious reading because of reporting bias.
Studies in headache disorders
In people who already have certain headache conditions, the early evidence points toward fewer headaches, not more. It is observational and small.
Idiopathic intracranial hypertension is raised pressure around the brain with no clear cause, and headache is a core symptom. A 2025 study drew on health records to match 193 patients with the condition who took tirzepatide against 193 who did not [9]. At 24 months, the tirzepatide group’s headache risk was 19.7% lower (risk ratio 0.803, 95% CI 0.668 to 0.966).
That is a retrospective comparison, not a randomized trial. People who were prescribed tirzepatide may have differed in ways the matching could not capture.
In migraine, the published tirzepatide evidence so far is a 2026 case series of two patients [10]. Both had fewer migraine attacks after starting the drug. Both also lost weight, which the authors name as a major confounder, and they call the cases preliminary observations.
Putting it together
Across the posted trials, headache on tirzepatide was common in absolute terms but mostly close to the comparison group, which is why it is missing from both label tables. The gap was clearest in people with type 2 diabetes, the group most exposed to low blood sugar.
The other side effects that cluster around dose increases are covered in does tirzepatide make you tired and tirzepatide dosage. For the two drugs side by side, see tirzepatide vs semaglutide, and to compare prescribers, the compounded tirzepatide rankings.