GLP-1s Linked to Increased Hypotension Risk in Hypertensive Patients

Patients treated for hypertension who use GLP-1 receptor agonists face higher rates of hypotensive events, according to research presented at ENDO 2026. Micah J. Eimer, MD, of Northwestern Medicine, reported that these episodes were most common in patients aged 65 and older and those with type 2 diabetes.

Dr. Eimer and his colleagues analyzed blood pressure changes in 54,682 patients from a large-scale electronic health record database. Every patient in the study was taking at least two medications for hypertension. The researchers stratified the group by whether they used GLP-1 drugs, including liraglutide (Victoza/Saxenda), semaglutide (Ozempic/Wegovy), or tirzepatide (Mounjaro/Zepbound).

The data showed GLP-1 users had higher hypotensive event rates at six months, with 10.2% compared to 8.7% for non-users. At 24 months, the rate for GLP-1 users was 18.1%, while non-users stood at 17.7%.

Why do GLP-1 medications increase the risk of low blood pressure?

Weight loss is a primary effect of these drugs, but researchers found it does not fully account for the observed hypotension. Dr. Eimer noted that medications which were appropriate for a patient’s original weight may no longer be suitable after losing 30 pounds.

Other biological mechanisms could be at play. According to Dr. Eimer, these may include a direct blood pressure-lowering effect of the GLP-1, dehydration, blood vessel relaxation, decreased sympathetic nervous system activity, or the potentiation of certain antihypertensive drugs.

Who is most at risk for hypotensive events?

The researchers identified two specific groups with the highest frequency of hypotensive episodes. Patients diagnosed with type 2 diabetes and those aged 65 years or older were the most affected.

Dr. Eimer told Healio that he observed patients complaining of fainting, dizziness, and lightheadedness in his clinic. He described hypotension as a more dangerous and “dreaded” potential side effect than the hypertension it aims to treat.

How should blood pressure be managed during GLP-1 therapy?

Clinical supervision is critical to prevent dangerous drops in blood pressure. Dr. Eimer stated that blood pressure needs to be monitored when therapy begins and during dose escalation.

Patients should be warned to report signs of low blood pressure immediately. Dr. Eimer expressed particular concern for individuals who obtain GLP-1 medications without ongoing clinical supervision.

Future research may be needed to better define risk factors. Dr. Eimer suggested that larger studies could look at the pace of weight loss and the specific types of blood pressure medications being used.

Frequently Asked Questions

Which GLP-1 medications were included in the study?
The study included liraglutide (Victoza/Saxenda), semaglutide (Ozempic/Wegovy), and tirzepatide (Mounjaro/Zepbound).

Does weight loss explain all cases of low blood pressure in these patients?
No. While weight loss makes some previous medication doses inappropriate, researchers found it does not fully account for the hypotension. Other factors like dehydration or direct drug effects may contribute.

What symptoms should patients watch for?
Patients should be alert for signs of low blood pressure, specifically lightheadedness, dizziness, and fainting.

How do you track your blood pressure when starting a new medication?