GLP-1 and Epilepsy: What UK Patients Should Know (October 2026)

01 · The core answer

Can you take GLP-1 with epilepsy?

Epilepsy does not automatically rule out a GLP-1 medicine, but it does mean the decision needs more care than usual. Your answer depends on which anti-seizure medicines you take, how well controlled your seizures are, and your other health conditions.

The practical question is usually not whether the injection itself triggers seizures. It is whether slower stomach emptying alters how your regular tablets are absorbed. Mounjaro slows stomach emptying, so it can affect how quickly some oral medicines are absorbed, particularly when you start treatment or increase the dose.¹¹³

For that reason, anyone with epilepsy should involve both the prescriber and the clinician who manages their seizures.

02 · Your next step

What to do next if you have epilepsy

Your first step is a conversation, not an order. Write down every medicine you take, including the name, strength and timing of each anti-seizure medicine. Take that list to your neurologist or epilepsy nurse and ask whether a GLP-1 medicine is suitable for you and whether they want to monitor you more closely.

If your specialist is comfortable, the next step is a consultation with a prescriber who has your full list. Our free online consultation is reviewed by a GPhC-registered prescriber, and if the prescriber decides the treatment is not suitable, the order is refunded automatically in full. Our weight loss clinic explains the process.

If anything about your epilepsy is unstable or recently changed, speak to your specialist before considering any weight-loss medicine at all.

Related guide: Can you take mounjaro if you have epilepsy.

03 · What GLP-1 medicines are licensed for

What GLP-1 medicines are licensed for

GLP-1 medicines are licensed for weight management and diabetes. They are not licensed to treat or prevent epilepsy. Mounjaro is the brand name for tirzepatide, a once-weekly injectable prescription medicine made by Eli Lilly. In the UK it is licensed for weight management in adults and for type 2 diabetes.¹

A medicine is only a treatment for a condition when it has a licence for it. If you are seeing claims that a weight-loss injection will control seizures, treat them with caution and ask your specialist.

Mounjaro is available on the NHS, but access is being phased in over several years. NICE recommends it for adults with a BMI of at least 35 plus at least one weight-related condition, and the NHS primary-care rollout began in June 2025 with the highest-need groups first (initially BMI 40+ with four or more qualifying conditions).⁴⁶ If you have epilepsy and are asking your GP about NHS access, mention your seizure medicines at the start of the conversation.

04 · Stomach emptying and seizure tablets

Stomach emptying and anti-seizure tablets

The main practical link between GLP-1 medicines and epilepsy treatment is absorption. Tirzepatide activates two natural gut-hormone receptors, GIP and GLP-1. Together these help regulate appetite, slow how quickly the stomach empties, and improve the way the body responds to insulin.¹

When the stomach empties more slowly, a tablet may reach the gut later than it normally would. For many medicines this makes little difference. For medicines where the margin between too little and too much is narrow, timing can matter more. The product information tells people to mention warfarin or other narrow-margin medicines, insulin and sulfonylureas.¹¹³

Your prescriber and specialist, who know your regimen, will judge how this applies to your own anti-seizure medicines.

Do not change the timing or dose of your anti-seizure tablets yourself. Any adjustment should come from the clinician who manages your epilepsy.

05 · Reading the research headlines

Reading the research headlines

You may have seen reports that people taking GLP-1 medicines had a lower risk of seizures or epilepsy, and that these drugs may protect the brain.

A finding of lower seizure risk in a group of people taking a medicine is not the same as a licence to treat epilepsy. Studies of this kind observe what happened to people who were prescribed the drug for other reasons. They cannot show that the medicine caused the difference, and they cannot tell any one individual what will happen to them.

It is a reason for researchers to investigate further, not a reason to start a weight-loss injection in the hope of fewer seizures.

If you are curious, ask your neurologist what the current research means for your own situation. They can tell you whether it changes anything for you.

06 · Brain and neurological questions

What do GLP-1 medicines do in the brain?

Tirzepatide helps regulate appetite, and in practice most people feel fuller sooner and less hungry between meals, which supports a reduced-calorie diet.¹

If you notice anything new or worrying after starting treatment, such as a change in how often your seizures happen, tell your prescriber and your specialist promptly.

You can also report suspected side effects yourself through the MHRA Yellow Card scheme.¹⁹ Reports help regulators spot patterns, and you do not need to be certain the medicine caused the problem to make one. Serious side effects are uncommon but need urgent attention. Seek immediate medical help for: severe, persistent stomach pain that may spread to your back, with or without vomiting (possible pancreatitis); pain in the upper right abdomen, fever or yellowing of skin/eyes (possible gallbladder problems); or signs of a severe allergic reaction such as swelling of the face or throat and difficulty breathing.

07 · Tablets, other medicines and low blood sugar

Other medicines to mention

Anti-seizure medicines are only part of the picture, so give your prescriber a complete list. Tell them about everything you take, especially warfarin or other narrow-margin medicines, insulin, or sulfonylureas, where doses may need reducing to avoid low blood sugar.¹¹³ No adjustment is needed for paracetamol.¹³ Mounjaro slows stomach emptying, which can reduce how well oral contraceptive pills are absorbed. The SmPC advises switching to a non-oral method, or adding a barrier method (such as condoms), for 4 weeks after starting Mounjaro and for 4 weeks after each dose increase.

If you also have diabetes, that makes the conversation with your care team more important, not less. Several of your medicines may need to be reviewed together rather than one at a time.

Bring over-the-counter products and supplements to the discussion as well. Some people with epilepsy are cautious about supplements marketed as natural alternatives to GLP-1 medicines. These are low-cost supplements with no clinical oversight, and their dosing is not standardised. Their makers often make dramatic weight-loss claims that we cannot support. Ask your specialist before adding any of them.

08 · Weight-loss options and epilepsy

Other weight-loss options if you have epilepsy

If a GLP-1 medicine does not suit you, other routes exist, and your specialist can help you weigh them. We have a separate guide on weight loss injections and epilepsy, and one on orlistat and epilepsy considerations.

09 · Starting treatment safely

Starting treatment safely if your specialist agrees

If your specialist agrees that treatment is reasonable, plan the start carefully. Because the effect on absorption is most relevant at the start and when the dose rises, those are the points to be most watchful.¹

Useful habits include keeping a simple diary of your seizure pattern and any symptoms, taking your anti-seizure medicines as your specialist has directed, and telling your prescriber before each dose increase. Repeat orders re-check suitability, and nothing ships automatically.

Mounjaro is a prescription-only medicine, supplied only after an online consultation reviewed by a GPhC-registered prescriber. It is used alongside a reduced-calorie diet and increased physical activity. Individual results vary. This page is information, not a substitute for medical advice.

If you stop treatment, the medicine does not leave your body at once. Tirzepatide has a half-life of about five days, so after a final dose it takes roughly four to five weeks to clear the system, and nothing needs doing while it clears.¹