Mounjaro drug interactions: Are there any medicines you should avoid?
The last thing you want is for something to throw a wrench in your progress.

Key takeaways
Starting your weight loss journey with Mounjaro? Youâre not alone in wondering what medicines you cannot take with Mounjaro and if this weight loss wonder and other medications might clash like oil and water.
Mounjaro, a popular GIP/GLP-1 receptor agonist, is a powerful tool in the fight against stubborn weight, helping to suppress appetite, control cravings, and improve metabolic function [1].
But before you start shedding pounds, itâs important to understand certain drug interactions and know if this injectable medication plays nicely with everything else in your medicine cabinet, including herbal supplements and even some foods or drinks.Â
After all, the last thing you want is for something to throw a wrench in your progress â or worse, cause unwanted side effects.
Read on as we take an informative dive into Mounjaro and possible interactions with other drugs and how to navigate them so you can stay safe and on track.
What medicines can you not take with Mounjaro?
When youâre trying to lose weight, the last thing you want is for a prescription or over-the-counter medication to slow you down or cause unwanted side effects.
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The good news is that Mounjaro is generally well-tolerated [2], but that doesnât mean you can throw caution to the wind.Â
Like any medication, Mounjaroâs effectiveness can be influenced by other substances youâre taking (like certain diabetes medications) or even by certain foods you eat or if you drink alcohol.
There are a few things to watch out for, including specific medications, herbal supplements, and dietary choices that may either reduce how well Mounjaro works or create unwanted complications [3].
By being mindful of these potential drug interactions, you can keep things running smoothly and enjoy the full benefits of your weight loss journey with Mounjaro.
Letâs go through some of the common interactions to help you stay on track.
5 potential Mounjaro interactions
Although Mounjaro is a game-changer in the world of weight loss, itâs always smart to check if it could interact with any other medications you might be taking, including all oral medications, whether prescription or over-the-counter.
Like any effective treatment, Mounjaro works best when itâs part of a well-rounded health plan, and that includes making sure it doesnât clash with other prescriptions or supplements.Â
Even the best weight loss tools can lose their effectiveness if they donât play nice with your other meds. Thatâs why it's crucial to regularly review your medication list with your healthcare provider and stay informed about any possible interactions.
Hereâs a list of some key drug interactions to keep an eye on so you can stay ahead of the game and avoid any surprises.
Insulin
If youâre taking insulin to manage diabetes and blood sugar, youâll want to pay special attention here. Mounjaro can work wonders in regulating blood sugar, which is great for weight loss but could mean double trouble when combined with insulin.Â
Both medications help lower blood glucose levels, and when used together, thereâs a higher risk of hypoglycaemia (aka, low blood sugar).
This could leave you feeling dizzy and weak, and reaching for the nearest snack to stabilise your levels [3]. Speak to your doctor or pharmacist about how to balance these diabetes medications safely.
If your doctor prescribes Mounjaro alongside insulin, theyâll likely adjust your insulin dosage to keep things running smoothly.
Metformin
Another common diabetes medication, metformin, often works alongside GLP-1 medications like Mounjaro. But donât worry, these two are more like best mates than frenemies.
Metformin and Mounjaro can complement each other quite well in managing blood sugar and working to lower your blood sugar level. [4]Â
That said, itâs always best to have a chat with your healthcare provider about how they interact in your specific case, especially if youâre concerned about low blood sugar or gastrointestinal side effects or have a personal or family history of complications with these conditions.
Birth control pills
Hereâs where things get a little tricky. Thereâs evidence that Mounjaro can affect the absorption of oral contraceptives (yes, weâre talking about the birth control pill here), making them less effective. [5]Â
No one wants an unplanned surprise, right?
To be safe, itâs advised that those on birth control pills either switch to a non-oral form of contraception or take the pill at least 1 hour before or after their Mounjaro injection.Â
Blood pressure medication
If youâre already managing high blood pressure (or low blood pressure) and are taking medication for it, youâll need to keep an eye on how Mounjaro might interact. Because Mounjaro can affect your appetite and the way your body processes food, it may have an impact on your blood pressure, too [6].
In some cases, losing weight can lower your blood pressure naturally, which is great, but it might mean your current dosage needs adjusting.Â
Donât just wing it. Get in touch with your doctor to avoid feeling faint or dizzy if your blood pressure dips too low.
Thyroid medications
If youâre on medication for thyroid issues, particularly hypothyroidism, you might be wondering if Mounjaro will throw a spanner in the works. While Mounjaro doesnât directly interfere with thyroid medications, itâs always a good idea to be cautious.Â
GLP-1 medications, in rare cases, have been linked to thyroid tumours in animal studies, though thereâs no definitive evidence for humans [7].
Still, itâs something to discuss with your doctor or pharmacist, especially if youâre on thyroid medication like levothyroxine, or have a personal or family history of thyroid cancer [8].
Can Mounjaro interact with herbal supplements?
You might be wondering, "Surely my herbal supplements canât cause any problems, right?"
While natural remedies can seem innocent, theyâre not always harmless when combined with prescription medications like Mounjaro, just like other drugs.
St. Johnâs Wort
Ah, the trusty St. Johnâs Wort, often praised for its mood-boosting abilities. When it comes to Mounjaro, this herbal supplement can mess with your bodyâs metabolism by speeding up the breakdown of certain medications in your system [9].
So, if youâre using it for its calming effects, it might just make your Mounjaro treatment less effective in doing its job.Â
Stick with caution here and talk to your prescriber before mixing the two.
Ginseng
Ginseng is often used to improve energy levels and reduce stress, but when combined with Mounjaro, it may alter blood sugar levels [10]. Since Mounjaro is designed to regulate glucose, adding ginseng to the mix could lead to fluctuations in your blood sugar.
As always, check in with your doctor or pharmacist provider if youâre a fan of this root-based supplement.
Garlic supplements
Garlic might add a nice zing to your meals, but in supplement form, itâs another story.
Garlic supplements can have a blood-thinning effect, and when you combine that with Mounjaroâs ability to regulate metabolism, you might end up with a little too much thinning for comfort [11].
If youâre taking blood-thinning medications as well, youâll definitely want to avoid garlic supplements.
Are there any food or drink interactions to consider?
The kitchen is where the magic happens â but itâs also where certain foods and drinks might cause Mounjaro interactions.
While there arenât any strict "do not eat" lists, there are a few things to keep in mind.
Alcohol
Alcohol and Mounjaro might not be the best drinking buddies. Both alcohol and Mounjaro can lower your blood sugar, which means drinking alcohol can lead to some unwanted side effects like dizziness, severe nausea, or even fainting if your blood sugar drops too low [12].
Plus, alcohol is full of empty calories, which might slow down your weight loss progress. Moderation is key, but if youâre in doubt, itâs always best to sip with caution.
High-sugar foods
Mounjaro helps control your appetite and cravings, so eating high-sugar foods might counteract its effects.
Sugary treats can spike your blood sugar levels, and since Mounjaro works to keep those levels steady, indulging in sweets might make it harder to achieve your weight loss goals.Â
Does this mean you can never enjoy dessert again? Of course not! Just be conscious of spikes in blood sugar and aim for moderation to let Mounjaro do its best work.
What are the common side effects of Mounjaro?
As is the case with any medication, Mounjaro is associated with several side effects. These might happen when or not a drug interaction occurs, and are worth being aware of:
- Nausea
- Diarrhoea
- Vomiting
- Constipation
- Abdominal pain
Thesse are typically easy to navigate and treat, especially if you let your doctor know about them as soon as you can.
Other, more serious side effects may include pancreatitis, gallbladder problems, hypoglycemia, severe digestive problems, and allergic reactions.
Starting your journey with Mounjaro
Now that youâre well-versed in what to avoid while on Mounjaro, youâre ready to embark on your weight loss journey with confidence.
Understanding how Mounjaro interacts with other medications means you can avoid any unwanted hiccups along the way, allowing you to focus on what really matters â achieving your weight loss goals.
The Juniper Weight Reset Programme makes it easier than ever to get started with medical treatment, helping you lose weight safely and effectively.
Mounjaro is designed to help you manage cravings, regulate your appetite, and supercharge your metabolism â all while keeping you feeling full for longer, so youâre less tempted by those sneaky snacks.
With Juniperâs programme, youâll also get access to unlimited consultations with prescribers, meaning you can get expert advice whenever you need it, not just as you're starting Mounjaro treatment.
Not to mention, the personalised coaching and 1:1 health tracking ensure that youâre on the right path every step of the way. And donât forget about the supportive community of like-minded people â together, you can celebrate wins, overcome challenges, and keep each other motivated.
Whether youâre just beginning or already a few steps into your weight loss journey, Juniper is here to help you achieve sustainable, long-term results.
Ready to take control of your health? Check your eligibility online and take the first step towards a healthier, happier you today!
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- https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0285197
- https://link.springer.com/article/10.1007/s40265-022-01746-8
- https://www.ncbi.nlm.nih.gov/books/NBK585056/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC10470858/
- https://pubmed.ncbi.nlm.nih.gov/37940101/
- https://heart.bmj.com/content/110/19/1165
- https://pmc.ncbi.nlm.nih.gov/articles/PMC9687454/
- https://www.drugs.com/drug-interactions/levothyroxine-with-mounjaro-1463-0-4363-20051.html
- https://www.tga.gov.au/news/safety-alerts/st-johns-wort-important-interactions-between-st-johns-wort-hypericum-perforatum-preparations-and-prescription-medicines
- https://pmc.ncbi.nlm.nih.gov/articles/PMC6943541/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC8031974/
- https://link.springer.com/article/10.1007/s40265-022-01746-8