Key Points

• Mounjaro users often report fatigue despite it not being listed as an official side effect in clinical trials
• Low energy may result from starting a higher dose, digestive side effects, sleep disruption, or blood sugar fluctuations
• Working with your healthcare provider and a registered dietitian can help manage tiredness on Mounjaro

Mounjaro (tirzepatide) has helped many people achieve A1c levels under 7% and lose up to 25 pounds. Despite these benefits, some experience low energy levels after starting the medication.

While fatigue is not listed as an official side effect in clinical trials, social media reports consistently mention extreme tiredness while taking Mounjaro.

If you're dealing with low energy on this medication, understanding why it happens and what you can do about it will help you get the most from your treatment.

What is Mounjaro?

Mounjaro is an FDA-approved medication to treat type 2 diabetes. Its active ingredient, tirzepatide, has been shown to effectively lower blood sugar levels while also helping with weight loss.

Gia Eapen, MD, explains, “This once-weekly injection mimics two naturally occurring hormones in your body: GLP-1 and GIP. These hormones help reduce appetite, create feelings of fullness, and lower blood sugar levels.”

Why does Mounjaro make you tired?

While Mounjaro can be effective, it does come with some common digestive side effects like nausea, stomach discomfort, and diarrhea. Interestingly, fatigue is not officially listed as a side effect in clinical trials. However, there is something to note here.

When researchers analyzed social media posts and online reports from individuals taking Mounjaro (and similar medications like Ozempic and Wegovy), many people mentioned feeling extremely tired and having low energy levels while on these medications.

Here are some potential reasons why you may be tired on Mounjaro.

1. Switched doses recently? It could be your body adjusting

Eapen, MD, says, “If you just switched to a higher Mounjaro dose, it may be that your body is adjusting to the higher dose. The fatigue effect could be temporary.”

If you do not see an improvement in your energy levels over the few weeks after starting the higher dose, consult your healthcare provider.

2. Digestive side effects may cause fatigue

Mounjaro side effects include digestive issues like nausea, diarrhea, decreased appetite, vomiting, constipation, stomach pain, bloating, and gas. These uncomfortable symptoms don't just affect your digestion. They can drain your energy too.

Think about it: the drug already reduces your appetite, but if you’re also queasy all the time or running to the bathroom frequently, you may not end up eating enough food during the day. In this case, you may not be getting the nutrients that your body needs for energy.

If you’ve been feeling exhausted and your digestive discomfort isn't improving, it's worth discussing with your doctor ways to manage these side effects while still benefiting from the medication.

3. It could be your sleep quality

Sleep problems are a common issue that many people taking Mounjaro, Ozempic, or Wegovy report. Users online frequently mention that insomnia is a common effect of these medications.

When your sleep is disrupted, you might find yourself lying awake at night or waking up frequently. Poor sleep quality directly impacts your energy levels the next day and leaves you feeling exhausted and sluggish. Some people also notice they get hungry when they wake up during the night and end up eating. These late-night cravings may work against weight loss efforts.

If your sleep quality does not improve over time, please consult your healthcare provider about ways to manage this side effect.

4. Is it low blood sugar (hypoglycemia)?

Low blood sugar is a common problem among people with diabetes. If you're on a higher dose of Mounjaro or combining it with other medications that lower blood sugar, you could experience hypoglycemia (when blood glucose drops to around 70 mg/dL or lower).

“If you suspect your blood sugar is low, check your levels and eat some carbohydrates to boost your energy,” says Eapen, MD. “Watch for other signs of hypoglycemia, like shakiness, a racing heart, sweating, dizziness, and trouble concentrating.”

Additionally, you may wake up feeling exhausted if you experience low blood sugar episodes during sleep; a continuous glucose monitor (CGM) or checking your morning blood glucose levels may help you learn more.

If fatigue continues to be an issue, talk to your doctor about whether your current dose is appropriate or if Mounjaro is the right medication for you.

5. Is it your diet?

Mounjaro works best when used with a nutritious diet and regular exercise. But adjusting to this medication and its side effects can create a challenging new reality for your daily life.

For example, how do you maintain regular meals when dealing with nausea or vomiting? If diarrhea is one of your side effects, your body might not be properly absorbing nutrients from the food you eat. You might also notice changes in your appetite or food preferences. Also, foods you once enjoyed might suddenly seem unappealing.

All these factors can impact your energy levels and raise questions about what diet works best while taking Mounjaro.

Consider working with a registered dietitian to find the best Mounjaro diet plan for you.

Final thoughts: Does Mounjaro make you tired?

Some Mounjaro users experience significant tiredness when they start taking the medication, along with improved A1c levels and weight loss. This exhaustion might stem from adjusting to a higher dose, experiencing digestive side effects, dealing with disrupted sleep, or managing blood sugar fluctuations.

If you’re feeling tired on Mounjaro, work with your healthcare provider to find the right dosage and consider consulting a registered dietitian to optimize your nutrition.

Frequently Asked Questions (FAQs)

1. What are the side effects of Mounjaro?

The most common side effects of Mounjaro include nausea, diarrhea, decreased appetite, vomiting, constipation, indigestion, and stomach (abdominal) pain. More serious side effects include low blood sugar, inflammation of the pancreas, allergic reactions, kidney problems, changes in vision, and gallbladder issues.

For a complete list of side effects or concerns regarding specific side effects you may be experiencing, consult your healthcare provider.

2. Does Mounjaro tiredness go away?

Eapen, MD, says, “Everyone responds differently to medication. Some people may find that their energy levels return as their body gets used to their dosage; others may continue to feel exhausted on Mounjaro. Track your energy levels and discuss your concerns with your doctor to help manage the side effects of Mounjaro, including feeling tired.”

3. How long does Mounjaro stay in your body?

Mounjaro (tirzepatide) takes about 30 days to fully leave your system.

4. Why am I not losing weight on Mounjaro?

There may be several reasons why you stopped losing weight on Mounjaro, including a lower medication dose, dietary choices, and changes to your exercise regimen. Plus, strong emotional eating triggers may threaten to derail your weight loss goals. If you’re on other medications, some of them may impact how you respond to Mounjaro.

Please talk to a healthcare provider to find out why you’re not losing weight on Mounjaro. Additionally, a registered dietitian can help you find the best Mounjaro diet plan tailored to your needs.

Boost your energy levels on Mounjaro with a personalized nutrition plan.

Find a registered dietitian who accepts your insurance.

The views expressed by authors and contributors of such content are not endorsed or approved by Fay and are intended for informational purposes only. The content is reviewed by Fay only to confirm educational value and audience interest. You are encouraged to discuss any questions that you may have about your health with a healthcare provider.