The GLP-1 Cliff: Stopping Mounjaro or Wegovy Erodes Heart Protection Faster Than the Weight Comes Back

Millions of people treat GLP-1 drugs as a course of treatment with an end date. New evidence suggests the heart may not see it that way.

The signal

A study in BMJ Medicine, led by Dr. Ziyad Al-Aly at Washington University School of Medicine in St. Louis, tracked 333,687 US military veterans with type 2 diabetes over three years. Of these, 132,551 took GLP-1 or dual GLP-1/GIP drugs (the class that includes Ozempic, Wegovy, Mounjaro and Zepbound), and 201,136 took older drugs such as sulfonylureas. The findings were reported by The Daily Record on 24 September 2026.

What the data shows

• Continuous users had an 18% lower risk of a major cardiovascular event (heart attack, stroke or death). That is roughly four fewer events per 100 people.

• Stopping for one year raised that risk by 14% compared with staying on the drug.

• Stopping for two years raised it by 22%, which effectively erases the protection gained.

• Patients who discontinued before 18 months showed no meaningful cardiac advantage over the older drugs by the end of the study.

• Restarting helped, but not fully. After a six-month break, risk stayed 4% to 8% above that of continuous users.

Why the protection fades

Weight regain is visible, and the metabolic reversal is not. Blood pressure, cholesterol and systemic inflammation drift back well before the lost weight returns. The drug takes about four to five weeks to clear the body, and appetite typically starts creeping back around weeks three to four. UK pharmacist Palvinder Deol of Happy Pharmacy notes that people watch the scale while the risk profile shifts underneath.

The wider picture

UCL research in BMC Medicine estimates that about 1.6 million UK adults used weight-loss injections in the past year. Use is twice as common among women and highest in middle age. Among people actively trying to lose weight, uptake is about 30% in Glasgow, 28% in Manchester, 26% in Belfast and 25% in Liverpool. The stop-start decisions in this study are therefore being made by a very large population, often for reasons of cost, supply or side effects.

Our read

Two points shape how to interpret this:

• The study is observational and covers veterans with type 2 diabetes. It shows a strong association, not proof of cause, and the results may not transfer directly to people using these drugs purely for weight loss.

• The policy signal is stronger than the clinical one. If the benefit depends on continuity, then price hikes, shortages and short prescription cycles carry a hidden cardiac cost. Health systems and insurers that ration supply may be trading short-term savings for downstream cardiovascular events.

Practical takeaways

• Don't let the pen simply run out. Any planned stop should be a tapering or transition plan agreed with your prescriber or pharmacist.

• Plan for appetite, nutrition and blood sugar in the weeks after stopping, as this is when regain pressure begins.

• If you have diabetes, stopping without a replacement can cause rapid blood sugar spikes and compound cardiac risk.

• If cost or supply is the problem, raise it before you stop. Switching or bridging is safer than a gap.

This is not medical advice. Speak to your doctor or pharmacist before changing any medication.

Sources: The Daily Record (Charlotte Smith, 24 Sept 2026); BMJ Medicine; UCL / BMC Medicine.