Imagine that you’ve just started taking Mounjaro: you’re excited to settle into your new routine and to reach your health goals. But after a few weeks, you realise that you’re feeling more tired than usual. What’s going on?
Tiredness is a side effect of Mounjaro, so it’s possible that the medicine is causing your fatigue. Usually though, this will go away on its own.
Still, it’s helpful to understand why tiredness happens on Mounjaro and what you can do about it. Read on—we’ve answered all your questions below.
Is it common to feel fatigue while taking Mounjaro?
In a word: yes. According to the patient information leaflet for Mounjaro, up to one in ten people may feel tired or fatigued while using the medicine.
Side effects tend to come on when you just start the medicine or increase your dose. And most of the time, they’re nothing serious and will clear up.
Why does Mounjaro make you tired?
So what’s the link between Mounjaro and tiredness? We don’t have enough scientific evidence to say for sure. But based on our understanding of how the medicine works, there are a few possible explanations for fatigue on Mounjaro.
You’re in a calorie deficit
Mounjaro is meant to be used alongside a reduced-calorie diet (you eat less energy than you burn each day) and regular exercise.
But being in a calorie deficit can cause your body to panic, because it thinks you might be in danger of starving. So, it tries to conserve the energy stores you’ve got—causing your metabolism to slow down. This might make you feel tired.
You’re dehydrated
Vomiting and diarrhoea are also common side effects of Mounjaro. And if you don’t replace the fluids you lose, you can get dehydrated. Fatigue is one of the most common symptoms of dehydration.
You’ve got low blood sugar (hypoglycaemia)
This would be more of a concern for people with type 2 diabetes. One of the ways Mounjaro works to make you feel full is by stimulating the release of insulin, which also keeps your blood sugar under control.
If you’re taking another medicine that affects your blood sugar as well, your levels could drop too low. Feeling tired is a sign of hypoglycaemia.
Other side effects have disrupted your sleep
Plus, Mounjaro can bring on a few other side effects that could make you feel tired by messing with your sleep. For example, having nausea, diarrhoea, indigestion, or constipation can all keep you from drifting off.
How can I reduce tiredness and fatigue while taking Mounjaro?
We’re glad you asked. Here’s some tips for dealing with Mounjaro fatigue.
Build a good sleep routine
It sounds obvious, but: if you sleep well, you’ll feel less tired. Though we know that can be much easier said than done!
The best way to get a good night’s rest is to improve your sleep hygiene, which is your sleeping habits and environment. Try to go to bed at the same time every night and create a calming routine around bedtime that you’ll stick to. Ideally, you want to get 7-9 hours of sleep each night.
Exercise regularly
Though you might feel tired right after a workout, regular exercise can elevate your overall energy levels. The NHS notes that even a single, 15-minute walk can make you feel more energised.
This is because exercise can boost the circulation of oxygen through your system, improve your metabolism, reduce stress levels and help you get a better night’s rest. Try to do 150 minutes of moderate-intensity exercise and two strength sessions each week.
If you experience tiredness and fatigue at the start of your weight loss journey, swapping intense workouts for lighter activities like yoga or gentle walks may help until you feel better. Following this, you can gradually build your activity level back up.
Eat a balanced diet
If your body isn’t getting enough of the essential nutrients it needs to function at its best, you might feel tired. For example, it’s estimated that between 3-20% of adults are deficient in vitamin B12—and this can make you feel weak and tired, among other things.
Choosing foods that release energy more gradually, like wholegrains, versus those that will give you a rush but won’t fill you up (like foods high in saturated fat and sugar) can also help stabilise your energy levels.
Lose weight
And last, but not least: losing weight can make you feel less tired and more energised.
For one, it helps improve your metabolism, which means that your body uses energy more efficiently. You might also sleep better and have less stress, too—both of which can make you feel less fatigued.
Side effects support at Voy
"If you're using Voy and you experience any side effects, rest assured that our expert clinicians are just a message or phone call away. They can adjust your dose, prescribe medication to ease your symptoms, or simply offer reassurance.
Everyone responds differently to weight loss treatment and we'll help you find what feels right for you."
When to consult your healthcare provider
It’s normal to feel tired now and then—we’ve all had those days where we just want to sink into the sofa! But if you’ve been feeling tired for a few weeks and it’s affecting your day-to-day life, that calls for a visit to your doctor.
You should also check in with your provider if you’ve been having other symptoms too, like mood changes or if you’ve been told you’re making snorting or choking noises when you’re asleep.
Your weight loss journey
Tiredness might not be one of the most commonly reported side effects of Mounjaro, but it can happen—and to reiterate, it’s usually nothing to worry about. Though if it gets worse or doesn’t go away, do get in touch with your doctor.
And if you do try Mounjaro injections, it’s super important to monitor your symptoms and keep tabs on how you’re feeling throughout your journey. We can help here: via our weight loss programme, our team of clinicians and coaches will give you one-to-one support and guidance at every step. Plus, we’ll post your medicine to you each month.
If you stick to your routine for over a year, you might lose around 25% of your starting weight.
Find out if you’re eligible for the programme by taking this short quiz. It won’t take longer than a few minutes.
FAQs
Is tiredness a common side effect of Mounjaro?
Yep—up to one in ten people might experience tiredness on Mounjaro. Though it’s not as commonly reported as some other symptoms, like nausea, vomiting, diarrhoea, and constipation. So, if you’re feeling fatigued on Mounjaro, you aren’t alone.
Should I stop taking Mounjaro if I feel tired?
Typically, you would only stop taking the medicine if your side effects were interfering with your day-to-day life. After all, Mounjaro tiredness isn’t a sign that the medicine isn’t working. So it would be a decision between you and your provider.
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