Blood pressure was one of the extra measurements in the big trials behind Zepbound and Wegovy, and it went down. The drop was a few points of systolic pressure, the top number, more than on placebo [1] [2]. That's a real effect, but it is a side result of a weight-loss drug, not an approved use. The same labels also warn about blood pressure falling too low. Here are both sides.
Systolic pressure fell about 4 to 10 points in the weight trials
The labels report the average change from each trial's start. People in the main Zepbound and Wegovy trials began with normal-to-high readings, a systolic average of about 123 to 131 mmHg [1] [2].
| Trial | Length | Drug, dose | On the drug | On placebo |
|---|---|---|---|---|
| Zepbound main trial, no diabetes | 72 weeks | Zepbound 5 / 10 / 15 mg | −6.6 / −7.7 / −7.4 | −1.0 |
| Zepbound trial, type 2 diabetes | 72 weeks | Zepbound 10 / 15 mg | −5.6 / −7.1 | −1.2 |
| Wegovy main trial, no diabetes | 68 weeks | Wegovy 2.4 mg | −6.2 | −1.1 |
| Wegovy trial, type 2 diabetes | 68 weeks | Wegovy 2.4 mg | −3.9 | −0.5 |
| Wegovy trial with intensive lifestyle therapy | 68 weeks | Wegovy 2.4 mg | −5.6 | −1.6 |
| Wegovy 7.2 mg trial, obesity | 72 weeks | Wegovy 2.4 / 7.2 mg | −8.5 / −10.1 | −4.8 |
| SELECT heart trial, Wegovy | 104 weeks | Wegovy 2.4 mg | −3.8 | −0.5 |
Zepbound prescribing information, Table 3 [1]; Wegovy prescribing information, Tables 7, 13 and 17 [2].
The bottom number, diastolic pressure, fell too: 4.5 to 5.0 mmHg on Zepbound across doses in its main trial, against 0.8 on placebo [1]. The difference between drug and placebo is the useful figure. For Zepbound 15 mg it was 6.4 mmHg systolic; for Wegovy 2.4 mg, 5.1 mmHg [1] [2].
The higher Wegovy dose went further. In the 72-week trial of Wegovy 7.2 mg in adults with obesity, systolic pressure fell 10.1 mmHg on 7.2 mg and 8.5 mmHg on 2.4 mg, against 4.8 mmHg on placebo, a difference of 5.3 mmHg for the top dose [2]. The placebo group dropped more in that trial than in the others, which is why the gap, not the raw number, is the fair comparison. The label's top dose is covered in Wegovy dosage.
The labels don't explain the drop
Neither label gives a reason blood pressure fell, and neither offers a mechanism for it. Both drugs were studied alongside a reduced-calorie diet and more physical activity, and both produced large weight losses, but the labels stop short of linking weight to blood pressure. What's clear is that neither label lists high blood pressure as something the drug treats [1] [2].
Blood pressure can also drop too far
The flip side is on the same labels. In Zepbound's two main weight trials, low blood pressure (hypotension) was reported in 1.6% of people on Zepbound vs 0.1% on placebo. It was more common in people also taking blood-pressure medicine, 2.2% vs 1.2% in those who weren't, and it "also occurred in association with gastrointestinal adverse events and dehydration" [1].
Wegovy's label tells a similar story. Reactions related to low blood pressure were reported in 1.3% on Wegovy vs 0.4% on placebo, and fainting (syncope) in 0.8% vs 0.2%. Some were tied to stomach side effects and fluid loss, and they were more common in people on blood-pressure medicine [2]. In the Wegovy trial in teens aged 12 and older, hypotension was reported in 2.3% on Wegovy.
| What was reported | On the drug | On placebo |
|---|---|---|
| Zepbound: low blood pressure | 1.6% | 0.1% |
| Zepbound: low blood pressure, also on blood-pressure medicine | 2.2% | Not given |
| Zepbound: low blood pressure, not on blood-pressure medicine | 1.2% | Not given |
| Wegovy: reactions related to low blood pressure | 1.3% | 0.4% |
| Wegovy: fainting (syncope) | 0.8% | 0.2% |
Zepbound and Wegovy prescribing information, section 6.1 [1] [2].
Feeling dizzy or lightheaded when you stand, especially during a stretch of vomiting or diarrhea, is worth telling your prescriber about. Dizziness is on Zepbound's side-effect list too, at 4% to 5% vs 2% on placebo [1]. More on the stomach side and its knock-on effects is in Zepbound side effects.
Can Wegovy or Ozempic raise blood pressure?
The trial data point the other way. Every trial in the table above showed average systolic pressure going down, and none of the four GLP-1 labels lists high blood pressure as a side effect; the word appears only in descriptions of who was enrolled [2] [3] [1] [4].
What does go up is heart rate. Wegovy raised resting heart rate by 1 to 4 beats per minute on average, Zepbound by 1 to 3 and Mounjaro by 2 to 4 [2] [1] [4]. Wegovy's label asks prescribers to check heart rate regularly and tells patients to report a racing heartbeat at rest [2]. For Wegovy's full safety picture, see is Wegovy safe?
If you take blood-pressure medicine
This is the group the labels flag. Low blood pressure was more common on Zepbound and Wegovy in people also taking blood-pressure medicine [1] [2]. Tell your prescriber about every blood-pressure pill you take before you start, and report dizziness or fainting. Whether any dose of your blood-pressure medicine should change is a decision for the clinician who prescribes it, made from your readings, never one to make on your own.
High blood pressure can also matter for coverage. Medicare's GLP-1 program lists a BMI of 30 or higher with uncontrolled high blood pressure as one way to qualify [5]; the details are in does Medicare cover Zepbound?
Ozempic and Mounjaro: approved for heart risk, silent on blood pressure
Ozempic and Mounjaro are type 2 diabetes drugs, and their labels don't report blood pressure results from their trials [3] [4]. Both do carry a heart indication in type 2 diabetes. Ozempic is approved to reduce the risk of major heart events in adults with type 2 diabetes and established heart disease, and Mounjaro in adults with type 2 diabetes at high risk of those events [3] [4]. Wegovy has a heart indication too, for adults with established heart disease and obesity or overweight [2].
Those heart approvals are about outcomes such as heart attack and stroke, not blood pressure readings. How the two tirzepatide and semaglutide weight brands compare overall is in Zepbound vs Wegovy, and Mounjaro's safety record in is Mounjaro safe?
See how the 88 compounded semaglutide providers we score compare on monthly cost and care.