Mounjaro and epilepsy: what the evidence shows
GLP-1 receptors are present throughout the brain, not just in appetite-regulating areas, and several lines of evidence point towards potential neuroprotective effects.
A 2026 retrospective cohort study published in Epilepsia, using electronic health records from the multinational TriNetX network, looked at 8,688 matched pairs of adults with epilepsy and type 2 diabetes.
Those starting a GLP-1 receptor agonist (including tirzepatide) had an 18% lower risk of seizure recurrence compared with those starting other glucose-lowering (blood sugar-lowering) medications, alongside lower rates of hospitalisation, status epilepticus (prolonged seizure), and all-cause mortality.1
A separate 2024 meta-analysis of 27 randomised controlled trials, published in Epilepsia Open, found that newer glucose-lowering drugs were associated with a 24% lower risk of new-onset late-onset seizures and epilepsy compared with placebo, with the benefit driven by GLP-1 receptor agonists.3
Still, these studies have limitations. Both are observational, so they can’t prove the medication itself is causing the lower seizure risk rather than other differences between the groups being compared.
There’s also a published case report of one person experiencing a serious, prolonged seizure (status epilepticus) shortly after starting semaglutide, so individual responses may vary.5
Broadly, the impact of GLP-1 medications on epilepsy seems positive. There’s no evidence that GLP-1 medications increase seizure risk in most people with epilepsy, and there may be some benefit.
However, no randomised trials have directly tested Mounjaro in people with epilepsy.
How Mounjaro works
Mounjaro is a once-weekly injection containing tirzepatide, which mimics two gut hormones, GLP-1 and GIP. It reduces appetite by acting on appetite-regulating areas of the brain, and slows gastric emptying so food stays in the stomach longer.6
In the SURMOUNT-4 trial, participants who continued tirzepatide treatment from the start of the study through week 88 achieved a mean weight loss of approximately 26%.7
The slowed gastric emptying is the mechanism most relevant to epilepsy, because it can affect how oral medications, including AEDs and oral contraceptives, are absorbed.
Anti-epileptic drug interactions
There are no known direct pharmacological interactions between tirzepatide and AEDs.6
The clinical concern is indirect: tirzepatide slows gastric emptying, particularly when treatment is first started and after each dose increase, which can change the rate at which oral medications are absorbed.
For most AEDs, small changes in how quickly the medication is absorbed are unlikely to cause problems.
The concern is greater for AEDs where the difference between an effective dose and one that causes side effects is small.
For these medications, even modest changes in blood concentration can affect either seizure control or side effect risk.
AEDs that may warrant closer monitoring during Mounjaro initiation and dose increases include phenytoin, carbamazepine, lamotrigine, and valproate.
Your neurologist may want to check drug levels during these periods, particularly if you’ve had stable control for some time.
If you experience persistent vomiting from Mounjaro side effects, this can also affect AED absorption.
If you can’t keep medication down, contact your neurologist or epilepsy specialist nurse for advice rather than waiting for your next routine appointment.
Significant weight loss can also change how some AEDs are distributed in the body. As your weight drops, your AED dose may need to be adjusted.
Contraception, HRT, and pregnancy
For women with epilepsy of childbearing age, particularly those on valproate, the contraception implications of starting Mounjaro need planning before the first dose.
Tirzepatide reduces the effectiveness of oral contraceptives
The MHRA advises that women taking tirzepatide should switch to a non-oral contraceptive method, or add a barrier method like condoms, for 4 weeks after starting Mounjaro and for 4 weeks after each dose increase.8 This applies specifically to tirzepatide; semaglutide doesn’t carry the same warning.
Non-oral methods that remain fully effective include the intrauterine device (IUD or coil), the implant, the contraceptive injection, the patch, and the vaginal ring.
Mounjaro and valproate
The MHRA Pregnancy Prevention Programme requires women of childbearing potential on valproate to use highly effective contraception because of the high risk of birth defects (around 11% of babies exposed to valproate in pregnancy) and neurodevelopmental disorders (up to 30-40%).9
If you’re on valproate and considering Mounjaro, the impact on oral contraceptive absorption needs to be discussed with both your neurologist and contraception provider before starting.
HRT is also affected
Tirzepatide can reduce the absorption of oral progesterone in HRT. The intrauterine system (IUS) or transdermal patches are usually preferred.
Pregnancy
Mounjaro isn’t recommended during pregnancy. If you’re planning to conceive, current advice is to stop tirzepatide at least one month before trying to become pregnant.
Pregnancy in women with epilepsy needs specialist input regardless of medication, so plan ahead with your neurologist.
Eating well with epilepsy on Mounjaro
There’s no single ‘epilepsy diet’. What you eat can influence seizure control through its effects on blood sugar levels and nutrient status, both of which become more relevant on Mounjaro as it lowers your hunger, so you eat less overall.
Keeping blood sugar stable
Hypoglycaemia (low blood sugar) is a recognised seizure trigger.10 Rapid blood sugar swings from refined carbohydrates can have a similar effect for some people.
Eating regular, balanced meals based on whole foods and rich in protein, fat, and fibre is the most practical way to keep blood sugar stable.
The Second Nature balanced plate model is a useful framework: half the plate vegetables, a quarter protein, a quarter complex carbohydrates, plus a serving of fat. The combination of protein, fibre, and fat slows the release of sugar (glucose) into the bloodstream.
Protein at every meal
Protein supports stable blood sugar and helps preserve muscle mass during weight loss. It also helps us feel fuller for longer, even when we’re eating less to support weight loss.
Good sources include chicken, red meat, turkey, fish, dairy, eggs, Greek yoghurt, beans, lentils, and tofu.
Healthy fats from whole foods
Adequate fat intake supports neurological function, hormone production, and absorption of fat-soluble vitamins.
Focus on whole-food sources: extra-virgin olive oil, avocado, nuts, seeds, oily fish (salmon, mackerel, sardines), full-fat dairy, and eggs.
Oily fish twice a week provides omega-3 fatty acids, which have anti-inflammatory properties.
Complex carbohydrates for steady energy levels
Fibre-rich carbohydrates are digested more slowly than refined ones, leading to a lower blood sugar rise after eating.
Choose wholegrain or sourdough bread, rolled oats, brown rice, potato, sweet potato, quinoa, beans and lentils, wholemeal pasta, and wholemeal couscous.
Folate-rich foods (vitamin B9)
Several common AEDs, including valproate, carbamazepine, and phenytoin, can deplete folate levels over time. Low folate is associated with fatigue, mood changes, and increased risk of birth defects in pregnancy.
Good sources include dark leafy greens (spinach, kale, broccoli), beans and lentils, asparagus, avocado, and eggs. Your GP or neurologist may recommend a folic acid supplement, particularly if you’re of childbearing age.
Eating three meals a day, even if you’re not hungry
Mounjaro significantly reduces appetite, and some people find they naturally start skipping meals because they’re not hungry.
Broadly, we don’t recommend missing meals during weight loss to maintain muscle, and ensure we’re providing our body with all the nutrients it needs to function well.
With epilepsy, missing meals can also increase the risk of low blood sugar levels, potentially increasing the risk of seizures.
Even on days when you don’t feel hungry, aim for three balanced meals, even if they’re smaller portions and you need to add protein-rich snacks in between.
Greek yoghurt with berries and nuts, scrambled eggs on sourdough, or a small bowl of porridge with seeds all provide protein, fat, and fibre.
A note on ketogenic diets
A medical ketogenic diet is an established treatment for drug-resistant epilepsy, particularly in children, supervised by specialist services.
It’s distinct from popular versions of the ketogenic diet used for weight loss or type 2 diabetes.
If you’re interested in ketogenic approaches for epilepsy specifically, this is something to discuss with your neurologist rather than starting independently while on Mounjaro.
Ketogenic diets are highly restrictive, and while there’s good evidence for their use with epilepsy, we’d only recommend trying it under the guidance of your healthcare team so they can monitor your nutritional status, as well as ongoing seizure recurrence.
Sleep, alcohol, and seizure triggers
Poor sleep is one of the most consistent seizure triggers across different epilepsy types.10
Maintaining a regular sleep schedule, with consistent bedtime and wake times, supports seizure control as much as medication adherence does.
Mounjaro can disrupt sleep in the early weeks through gastrointestinal side effects, particularly nausea and reflux.
Eating earlier in the evening, smaller portions at dinner, and avoiding lying down immediately after eating can help.
Alcohol is a well-established seizure trigger. It lowers the seizure threshold, disrupts sleep, and interacts with several AEDs.10
If you choose to drink, keeping intake low and consistent is safer than occasional heavy drinking.
Staying active with epilepsy
Exercise is generally safe for people with epilepsy and may improve seizure control.
A 2015 review in Seizure concluded that aerobic exercise rarely triggers seizures and that most people with controlled epilepsy should be encouraged to exercise.11
Starting small and building habits
Research on habit formation suggests it takes an average of 66 days for a new behaviour to become automatic, though this varies considerably between individuals.12
Starting with something small enough to do on a bad day, attached to an existing routine, gives the habit the best chance of sticking.
A 10-minute walk after lunch, or some gentle stretching before bed, are reasonable starting points.
Safety considerations
For people with uncontrolled seizures, certain activities carry additional risk.
The Pimentel review specifically advises against scuba diving and skydiving for people with epilepsy.11
Other activities to approach with care include:
- Swimming alone, which isn’t safe; always swim with someone aware of your epilepsy in a supervised pool
- Activities at height (climbing, gymnastics on apparatus), where a seizure could cause a fall
- Cycling on busy roads; a stationary bike or quiet routes would be better
These are practical adjustments rather than reasons to avoid exercise. Many people with epilepsy are fully active in sport, particularly when seizures are well controlled.
Types of movement that work well
Walking, supervised swimming, yoga, tai chi, light resistance training, and group exercise classes all work well.
As a guide, the NHS recommends 150 minutes of moderate activity a week, but this is a long-term target rather than a starting point.
Looking after your mental health
Depression and anxiety are more common in people with epilepsy than in the general population.
The unpredictability of seizures, restrictions on driving (the DVLA requires being seizure-free for 12 months before resuming driving in most cases), the side effects of some AEDs, and the social impact of the condition all contribute.
If you notice persistent low mood, loss of interest, increased anxiety, difficulty sleeping beyond what’s normal for you, or thoughts of self-harm, speak to your GP.
Cognitive behavioural therapy has good evidence for both depression and anxiety in people with epilepsy.
Some antidepressants are safe alongside AEDs, though your prescriber will need to check for interactions.
Connecting with others who understand can help reduce the sense of isolation that often accompanies epilepsy.
Epilepsy Action and Epilepsy Society both run support groups and online communities.
Weight, AED side effects, and self-image
Some AEDs cause weight gain as a side effect, particularly valproate, carbamazepine, and pregabalin.
Others, including topiramate and zonisamide, are associated with weight loss.
If AED-related weight gain is contributing to your decision to consider Mounjaro, it’s worth discussing whether an alternative AED might be appropriate before adding another medication.
AEDs and Mounjaro: practical considerations
| AED |
Weight effect |
Considerations with Mounjaro |
| Valproate |
Weight gain |
Pregnancy Prevention Programme requires highly effective contraception; tirzepatide reduces oral contraceptive efficacy. Discuss with a neurologist before starting. |
| Carbamazepine |
Weight gain |
Narrow therapeutic index; consider drug-level monitoring during Mounjaro initiation and dose increases. |
| Phenytoin |
Neutral |
Narrow therapeutic index; consider drug-level monitoring during Mounjaro initiation and dose increases. |
| Lamotrigine |
Neutral |
Narrow therapeutic index; consider drug-level monitoring during Mounjaro initiation and dose increases. |
| Pregabalin / Gabapentin |
Weight gain |
No specific interaction concern; standard monitoring. |
| Levetiracetam |
Neutral |
No specific interaction concern; standard monitoring. |
| Topiramate |
Weight loss |
Combined weight loss with Mounjaro may be significant; monitor closely. |
| Zonisamide |
Weight loss |
Combined weight loss with Mounjaro may be significant; monitor closely. |
Frequently asked questions
Can I take Mounjaro if I have epilepsy?
Yes. There are no known direct interactions between tirzepatide and anti-epileptic drugs, and recent research suggests GLP-1 receptor agonists may be associated with a lower risk of seizure recurrence in people with epilepsy.1
Always inform your neurologist before starting Mounjaro so they can monitor your AED levels and seizure control.
Will Mounjaro affect my AED absorption?
It can. Mounjaro slows gastric emptying, particularly when first started and after each dose increase, which may affect how quickly oral medications are absorbed.
For AEDs with a narrow therapeutic index (phenytoin, carbamazepine, lamotrigine, valproate), drug-level monitoring during these periods is sensible.
Will Mounjaro affect my contraception?
Yes, if you take an oral contraceptive. The MHRA advises switching to a non-oral method or adding a barrier method like condoms for 4 weeks after starting tirzepatide and for 4 weeks after each dose increase.8
Non-oral methods (IUD, implant, injection, patch, vaginal ring) remain fully effective.
I’m on valproate. Does this change anything?
Yes. Valproate carries a high risk of birth defects and developmental disorders if taken during pregnancy, and the MHRA Pregnancy Prevention Programme requires women of childbearing potential to use highly effective contraception.
Tirzepatide reducing oral contraceptive absorption needs to be discussed with both your neurologist and contraception provider before starting Mounjaro.9
Can losing weight change my seizure control?
It’s possible. Significant weight changes can affect how some AEDs are distributed in the body, potentially altering blood concentrations.
Keep your neurologist informed about your weight loss so doses can be adjusted if needed.
Is it safe to exercise with epilepsy?
Yes, and exercise may help reduce seizure frequency in some people.11 The main safety considerations involve avoiding activities with a high fall or injury risk if seizures aren’t fully controlled.
Scuba diving and skydiving are not generally recommended for people with epilepsy.
Can skipping meals trigger a seizure?
Yes, as low blood sugar levels are a known seizure trigger. Eating 3 balanced meals a day helps keep blood sugar levels from dropping too low, minimising the risk of a seizure.
Should I avoid alcohol on Mounjaro and AEDs?
Alcohol lowers the seizure threshold, disrupts sleep, and interacts with several AEDs.
If you choose to drink, keeping intake low and consistent is safer than occasional heavy drinking.
Could Mounjaro affect my mood?
The most common side effects are gastrointestinal. There’s no strong evidence linking Mounjaro to mood changes, but epilepsy itself carries a higher risk of depression and anxiety.
If you notice changes in your mood after starting Mounjaro, raise it with your healthcare team.
Will Mounjaro make my epilepsy fatigue worse?
Some people feel more tired in the early weeks of GLP-1 treatment, often related to eating less than usual. This usually improves as your body adjusts.
Focusing on nutrient-dense meals and staying hydrated helps. If fatigue is significantly worse than your baseline, speak to your prescriber.
Take home message
You can take Mounjaro if you have epilepsy. There are no known direct interactions between tirzepatide and AEDs, and the available research suggests GLP-1 medications may be associated with lower seizure recurrence rather than higher risk.
Still, Mounjaro does affect the absorption of oral medications. AEDs with a narrow therapeutic index may need drug-level monitoring during initiation and dose increases.
Oral contraceptives need a barrier method or switch to a non-oral method. Women on valproate need to plan contraception carefully before starting.
Stable blood sugar from regular meals, consistent sleep, and limited alcohol all support seizure control. Exercise is safe for most people with epilepsy and may help reduce seizure frequency.
Second Nature’s Mounjaro programme combines medication with support from registered dietitians and a structured habit-change programme, built around the balanced plate model and focused on sustainable changes.
In a 2025 study published in JMIR Formative Research, active subscribers on Second Nature’s semaglutide-supported programme lost an average of 19.1% of their body weight at 12 months, with 77.7% achieving at least 10% weight loss.13
Second Nature's Mounjaro and Wegovy programmes
Second Nature provides Mounjaro or Wegovy as part of our Mounjaro and Wegovy weight-loss programmes.
Why choose Second Nature over other medication providers, assuming you're eligible?
Because peace of mind matters.
We've had the privilege of working with the NHS for over eight years, helping people across the UK take meaningful steps toward a healthier, happier life.
Our programmes are designed to meet people where they are, whether that means support with weight loss through compassionate one-to-one health coaching, or access to the latest weight-loss medications (like Mounjaro and Wegovy) delivered alongside expert care from a multidisciplinary team of doctors, psychologists, dietitians, and personal trainers.
At the heart of everything we do is a simple belief: real, lasting change comes from building better habits, not relying on quick fixes. We're here to support that change every step of the way.
With over a decade of experience, thousands of lives changed, and a long-standing record of delivering programmes used by the NHS, we believe we're the UK's most trusted weight-loss programme.
We hope to offer you something invaluable: peace of mind, and the support you need to take that first step.
References
- AbuAlrob, M.A. et al. (2026). Seizure recurrence after GLP-1 receptor agonist initiation in adults with epilepsy. Epilepsia, 67(3), 1246-1255.
- Wigglesworth, S. et al. (2023). The incidence and prevalence of epilepsy in the United Kingdom 2013-2018: a retrospective cohort study of UK primary care data. Seizure, 105, 37-42.
- Sindhu, U. et al. (2024). Newer glucose-lowering drugs reduce the risk of late-onset seizure and epilepsy: a meta-analysis. Epilepsia Open, 9(6), 2528-2536.
- Wang, L. et al. (2021). Semaglutide attenuates seizure severity and ameliorates cognitive dysfunction by blocking the NLR family pyrin domain containing 3 inflammasome in pentylenetetrazole-kindled mice. International Journal of Molecular Medicine, 48(6), 219.
- Findeis, J., Kerling, F. and Winterholler, M. (2026). Semaglutide-induced status epilepticus. Clinical Epileptology.
- Electronic Medicines Compendium. (2026). Mounjaro KwikPen 2.5mg solution for injection in pre-filled pen – Summary of Product Characteristics.
- Aronne, L.J. et al. (2024). Continued treatment with tirzepatide for maintenance of weight reduction in adults with obesity: the SURMOUNT-4 randomized clinical trial. JAMA, 331(1), 38-48.
- Medicines and Healthcare products Regulatory Agency. (2026). GLP-1 medicines for weight loss and diabetes: what you need to know. GOV.UK.
- Medicines and Healthcare products Regulatory Agency. (2024). Valproate – reproductive risks. GOV.UK.
- Epilepsy Action. (2025). Seizure triggers.
- Pimentel, J., Tojal, R. and Morgado, J. (2015). Epilepsy and physical exercise. Seizure, 25, 87-94.
- Lally, P. et al. (2010). How are habits formed: modelling habit formation in the real world. European Journal of Social Psychology, 40(6), 998-1009.
- Richards, R. et al. (2025). A remotely delivered GLP-1RA-supported specialist weight management program in adults living with obesity: retrospective service evaluation. JMIR Formative Research, 9(1), e72577.
