lifestyle

Does GLP-1 Make You Tired and How Long Does It Last?

James Madison, GLP-1 Expert

James Madison, GLP-1 Expert

Jul 20, 2025

Jul 20, 2025

injection - Does GLP-1 Make You Tired?

Starting a GLP-1 medication like semaglutide can be exciting, but some people experience tiredness as a side effect. If you’re feeling fatigued and wondering, “Does GLP-1 make you tired?” you’re not alone. This article Does Semaglutide Cause Constipation? will help you understand whether tiredness associated with GLP-1 medications like semaglutide is normal, how long it may last, and what you can do to feel more energized during treatment.

To help you on your journey, MeAgain has developed an innovative app that sheds light on the realities of using the GLP-1 app, including potential side effects such as tiredness. With our user-friendly tool, you can track your symptoms, find helpful tips and resources to aid in your treatment adjustment, and connect with others on a similar path.

Table of Content

Does GLP-1 Make You Tired?

person is layong on sofa - Does GLP-1 Make You Tired?

GLP-1 medications are a class of drugs that imitate the natural incretin hormone GLP-1, released from the gut after eating. This hormone performs several key functions: it stimulates insulin secretion, reduces glucagon secretion, and slows gastric emptying, all of which contribute to lower blood sugar levels. 

Understanding GLP-1 Side Effects: Beyond the Common Digestive Issues

These medications are instrumental in managing blood sugar for individuals with type 2 diabetes and also support weight loss, regardless of diabetes status. Common examples include semaglutide (Ozempic and Wegovy) and liraglutide (Saxenda and Victoza). 

When initiating GLP-1 therapy, patients should be aware of potential side effects. While issues like nausea, constipation, cramping, headache, heartburn, and dizziness are frequently discussed, the experience of fatigue, particularly with semaglutide, is a noteworthy side effect that is perhaps less universally highlighted.

Fatigue: An Uncommon Side Effect of GLP-1 Medications

Numerous patients have reported feeling tired while taking the GLP-1 semaglutide medications like Ozempic. And even though it’s relatively minor compared to the possibility of ongoing nausea or headaches, constantly feeling run down may impact your lifestyle. 

So, why does semaglutide cause fatigue? We spoke to experts about what causes semaglutide fatigue and how to prevent this unexpected side effect.

A Surprising But Real Side Effect of GLP-1 Medications

Feeling tired is often associated with the use of semaglutide medications. In fact, a study from the University of Queensland calls fatigue the “second-most common side effect” of Ozempic. The study was a clinical trial, which noted that about 6.3 percent of participants reported feeling exhausted. 

And it turns out there’s a scientific reason for that, cardiology dietician Dr. Michelle Routhenstein, RD at Entirely Nourished, says it’s because of reduced appetite and slowed digestion: “These symptoms lead to lower calorie intake and potential nutrient deficiencies, which can decrease energy levels,” she explains. 

What’s Causing My Fatigue on Ozempic?

Semaglutide's primary role is to lower blood sugar levels by mimicking GLP-1, a naturally occurring hormone. This hormone reduces glucose production by your liver and increases its uptake by your body. A significant drop in blood sugar can lead to fatigue, a common symptom of hypoglycemia. 

Semaglutide can lower blood sugar too much, especially if combined with other glucose-lowering medications or if you have conditions like kidney or pancreas disorders that affect sugar processing. Close monitoring of blood sugar is essential, particularly if you frequently feel tired, to allow for timely adjustments to medication or diet.

Understanding GLP-1 Fatigue: Beyond Blood Sugar Swings

Semaglutide aids in weight loss by promoting feelings of fullness, which can lead to reduced calorie intake and subsequent weight loss. Your body's endocrine system needs time to adapt to this lower energy supply, often resulting in initial tiredness or lethargy. To manage this, consider eating smaller, more frequent meals, as this can also help stabilize blood sugar levels.

GLP-1 also affects the brain and nervous system, contributing to slower stomach emptying, which can cause feelings of sluggishness. This effect may be more noticeable when you first start or increase your dose.

The Crucial Role of Hydration in Managing Semaglutide Fatigue

Hydration is vital for energy. Semaglutide can cause nausea, vomiting, or diarrhea, potentially leading to dehydration, a known cause of fatigue. Increasing your fluid intake if you experience these side effects is crucial to maintaining energy levels.

While these factors offer insight into potential fatigue, it is always advisable to consult your healthcare professional if you are concerned about the side effects of your medication.

Risk Factors for Fatigue

Several factors can increase the likelihood of experiencing tiredness while using semaglutide: 

  • Dosage and Adjustment Period: The body needs time to adjust to semaglutide, and tiredness may be more pronounced during this period, especially with gradual dosage increases.

  • Individual Health Conditions: Conditions like type 2 diabetes can exacerbate fatigue, particularly as the body adjusts to better-managed blood sugar levels. 

  • Lifestyle Choices: A poor diet, lack of exercise, and inadequate sleep can all contribute to fatigue. Conversely, a balanced diet, regular physical activity, and proper rest can help mitigate this side effect. 

  • Hydration Levels: Dehydration can worsen tiredness. Staying well-hydrated is crucial while on semaglutide.

Related Reading

How Long Does Tiredness Last on Semaglutide?

doctor handing over medication - How Long

If you're experiencing fatigue or tiredness while taking this medication, you may wonder how long these symptoms are expected to last. The side effects of semaglutide will vary depending on the individual. You may not experience fatigue at all. Many patients notice that tiredness becomes more pronounced during the first few weeks as their body adjusts to the medication. 

Over time, as your body becomes more accustomed to the treatment, this side effect often diminishes. 

Understanding How GLP-1s Work

Firstly, recognize that semaglutide is a GLP-1 receptor agonist designed to help control blood sugar levels and aid weight loss. As part of its mechanism, it does two crucial things. It lowers the amount of sugar created by your liver and decreases the amount of sugar you absorb from food. This might result in drops in blood sugar levels and, consequently, tiredness.

Blood Sugar Monitoring for Fatigue

If you often feel tired, you may want to monitor your blood sugar levels closely. This is especially so if you're also on other blood sugar-lowering medications or have health conditions that affect your body's sugar processing, such as kidney or pancreas disorders. Try to keep a log of your blood sugar levels and how you feel to share with your healthcare provider. 

This could provide clues as to whether semaglutide dosage needs adjustment or if other interventions are needed.

Can Changes in Diet Cause Fatigue with Semaglutide?

Semaglutide promotes weight loss by making you feel fuller, thus causing you to eat less. A sudden and significant decrease in calorie intake may initially leave your body feeling fatigued as it adjusts to receiving less energy from the food you consume. 

Adjusting to a New Eating Routine

During this period of transition, try to split your daily food intake into several small meals rather than having two or three larger ones. This can help maintain more stable blood sugar levels throughout the day, which might help with managing feelings of tiredness. Be patient. Your body needs time to adjust to this new routine. 

Nausea and Dehydration

Semaglutide can have side effects like nausea, vomiting, or diarrhea, which can lead to dehydration and, consequently, feelings of tiredness. As such, maintaining sufficient hydration is key. Always ensure you drink enough fluids throughout the day. This is even more crucial if you are experiencing any of these side effects. 

Managing Tiredness with Semaglutide

Generally, most side effects from medications like semaglutide will diminish as your body becomes accustomed to the new medication and routine adjustments. Nevertheless, persistent feelings of tiredness should be shared with your healthcare provider. 

If you need advice, don't hesitate to connect with our Fella Health Care Team in the US, who can help you decipher your symptoms and provide valuable guidance. 

Dealing with Fatigue from Semaglutide

Understanding how medications affect individuals can be complex because each person reacts differently to medications. Factors such as age, gender, weight, other medication use, and overall health status can all affect how you experience a medication. Be patient with yourself while your body adjusts, and be proactive in reaching out to healthcare providers if the tiredness persists. 

Tips to Boost Energy While Taking Semaglutide

Semaglutide, a GLP-1 weight loss medication, can often leave users feeling tired. However, by understanding how semaglutide works and employing simple, healthy lifestyle habits, you can mitigate this tiredness and boost your energy levels. Semaglutide promotes weight loss by increasing feelings of fullness and reducing overall calorie intake. 

While this is beneficial for weight loss, a sudden decrease in calories can lead to fatigue as your body adjusts to the reduced energy intake. Some ways to deal with this include: 

Embrace Gradual Changes

Rapid reductions in calorie intake can result in a sudden decline in energy levels. Instead, try to slowly lower your intake, allowing your body time to adjust. 

Eat Regularly

Eating small amounts every few hours can help maintain stable blood sugar levels, preventing the dips that can cause fatigue. Include a balance of complex carbohydrates, lean proteins, and healthy fats in each meal to fuel your body effectively. 

Consider Meal Composition

Include a protein and a fiber source in every meal to achieve sustained energy release and stay fuller for longer. 

Stay Hydrated

Semaglutide may also influence your hydration status, as it can cause side effects such as:

  • Nausea

  • Vomiting

  • Diarrhea

  • Dehydration

It’s crucial to stay hydrated as dehydration can leave you feeling tired, lethargic, and even dizzy. Drink plenty of fluids. Try to drink at least eight 8-ounce glasses of water a day, and even more if you're in hot weather or engaging in physical activity that causes you to sweat. 

Move More

Exercise is another essential factor to consider when trying to boost your energy levels. Even though it may feel counterintuitive to move more when you’re tired, physical activity can boost energy levels rather than deplete them. Regular physical activity can help increase your energy levels by improving circulation and oxygen supply to your cells. 

Talk to a Doctor if Fatigue Persists

Always remember that you don't have to navigate your health journey alone. If you're concerned about low energy levels while taking semaglutide, don't hesitate to consult with a healthcare professional for guidance. The Fella Health Care Team is always here to answer your questions and provide tailored advice to address your unique needs and concerns. 

When to Talk to a Doctor About Semaglutide Fatigue

When it comes to managing semaglutide fatigue, knowing when to consult a healthcare professional is crucial. This will enable you to ensure that your treatment is not only practical but also safe and without any undue discomfort. 

Navigating Initial Fatigue on Semaglutide

Semaglutide, a GLP-1 weight loss medication, could cause some discomfort, such as fatigue, after you start taking it. This fatigue typically fades away as your body adjusts to this medication. Therefore, some level of fatigue could be expected in the initial days and weeks of treatment. When should you consult a doctor about fatigue? 

Here are a few scenarios: 

Persistent Fatigue

If your fatigue persists and doesn't improve after a few weeks, you should consult a healthcare professional. Persistent tiredness could indicate that your body isn't adjusting as anticipated and may necessitate adjusting your dosage or a change in treatment plan. 

Severe Fatigue

If the fatigue is severe and interferes with your daily activities, you should contact your healthcare provider immediately. You shouldn’t ignore debilitating fatigue that is hindering your life. 

Fatigue with Other Symptoms

If you notice other symptoms alongside fatigue, such as rapid weight loss, feeling disoriented, or confusion, it is wise to seek immediate medical attention. These could indicate severe conditions like dehydration or hypoglycemia (low blood sugar), and immediate medical attention can help prevent any serious complications. 

Reach Out for Help

Remember, you don’t need to deal with these concerns on your own. The Fella Health Care team in the US is available to assist you with any problems or issues you may encounter during your weight management journey with semaglutide. This combination of awareness, vigilance, and prompt action could significantly enhance the success and safety of your weight loss treatment. 

When to Seek Medical Advice for Semaglutide-Related Fatigue

While some minor discomfort and fatigue can occur during the initial phase of your treatment as your body adjusts to the medication, significant, persistent, or worsening tiredness should never be overlooked. 

Listening to your body and reaching out to medical professionals when necessary is key to a safe and effective semaglutide regimen. After all, the end goal is not just weight loss, but sustained health and well-being. Let Fella Health be your trusted partner on this journey.

Related Reading

  • Best Time of Day to Take Semaglutide for Weight Loss

  • How Long Do Semaglutide Side Effects Last

  • Does GLP-1 Make You Tired

  • How Long Does It Take for GLP-1 to Work

  • How Long Does It Take for Semaglutide to Suppress Appetite

  • Can Semaglutide Affect Your Period

  • GLP-1 Constipation

  • GLP-1 Dosage for Weight Loss

Download our GLP-1 App to Turn Your Weight Loss Journey Into Your Favorite Game

Starting Ozempic, Wegovy, or Mounjaro? The medication will help you lose weight, but avoiding nasty side effects like muscle loss and severe constipation takes work. MeAgain turns that work into a game with our adorable capybara that helps you hit your protein, fiber, water, and exercise goals. 

Celebrate Your Health Journey with Journey Card

Capture your incredible transformation with our Journey Card, because when you're changing this fast, you'll want to remember every milestone. It's the only all-in-one GLP-1 app that makes staying healthy as addictive as the results it delivers. 

Download MeAgain and turn your weight loss journey into your favorite game.

Related Reading

• How Long Do You Stay on Semaglutide for Weight Loss
• Can You Take Semaglutide With High Blood Pressure Medication
• Tirzepatide vs Semaglutide Side Effects
• Best GLP-1 Supplements
• Which GLP-1 is Best for Weight Loss
• Does Semaglutide Make You Tired
• How to Speed Up Weight Loss on Semaglutide
• Microdosing Semaglutide
• How Fast Does Semaglutide Work for Weight Loss