If you’re using a glucagon-like peptide 1 (GLP-1) drug to treat type 2 diabetes or for weight loss, you might wonder if tiredness is a normal side effect. Not everyone taking GLP-1 medications will feel worn out, but some people may develop fatigue (persistent exhaustion that doesn’t improve with rest).

There are several reasons GLP-1 drugs might make you feel more tired than usual. If you experience this effect, talk with your healthcare provider. They can help you decide if you should continue your treatment plan or consider other options that may work better for your body.

GLP-1 Drugs

GLP-1 drugs — also called GLP-1 agonists or GLP-1 receptor agonists — mimic a natural hormone in your body called glucagon-like peptide 1. GLP-1 hormones play several roles in your body, such as:

• Slowing down digestion, which helps you feel full longer and helps keep glucose (blood sugar) from rising too fast
• Telling your pancreas to release insulin, a hormone that lowers blood sugar levels
• Helping you feel fuller and more satisfied after meals by affecting areas of your brain that control hunger
• Blocking glucagon, another hormone that raises blood sugar levels

GLP-1 medications work the same way that the hormones do — they bind to receptors in your body to produce the same effects. Doctors often prescribe GLP-1 agonists to people who’ve been diagnosed with type 2 diabetes, obesity, or both. These medications help manage glucose levels and body weight. The term “obesity” refers to a score above 30 on the body mass index (BMI), a measure of height and weight that doesn’t always equate with health.

Examples of GLP-1 drugs approved by the U.S. Food and Drug Administration (FDA) include semaglutide (sold as Ozempic and Wegovy), liraglutide (Saxenda and Victoza), and tirzepatide (Zepbound), a dual GIP/GLP-1 receptor agonist. Insurance coverage for these drugs can vary, so your plan might cover all, part, or none of the cost.

GLP-1 Drugs and Tiredness

Feeling tired isn’t considered one of the most common side effects of GLP-1 agonists, but some people do experience fatigue while taking them. Sometimes, tiredness may stem from the drugs’ other side effects, such as:

• Nausea
• Vomiting
• Diarrhea
• Loss of appetite

Some members of MyObesityTeam shared that they feel tired when taking GLP-1 drugs. “My head hurts so bad from the pressure of feeling nauseous,” one member said. “It finally went away, but I felt very tired and sleepy” after starting a GLP-1 medication.

Why You Might Feel Tired When Taking GLP-1 Drugs

Because GLP-1 medications can lead to gastrointestinal issues and a lack of appetite, you may not get enough calories — either because you’re eating less or because your body can’t absorb what you eat before it leaves your system. When your body doesn’t get enough fuel, you might feel tired or weak. You may feel like you can’t do as much as usual or that you run out of energy sooner. These symptoms are more likely to occur at certain times during your GLP-1 treatment — for example, when starting the medication or after a dose increase.

It can also be hard to eat more — even if you know you need the calories — when you’re already feeling full or nauseated. Your healthcare provider may suggest that you lower your dose or even stop using the GLP-1 drug until you feel better. You can also try avoiding foods that may trigger nausea while on GLP-1 medications.

GLP-1 medications may also cause dehydration in some people, especially if they’re vomiting or having diarrhea. Not drinking enough water and fluids can also cause tiredness. Be sure to stay well hydrated while on GLP-1 medications.

A few people may get infections more easily or develop headaches when using GLP-1 agonists. Being ill or having ongoing pain can also lead to feeling more tired than usual.

When To Get Help for Tiredness

Some people taking GLP-1 drugs choose to wait out the tiredness as their body adjusts. However, if tiredness or fatigue interferes with your daily life, talk with your doctor. They may adjust your dose, switch your medication, or suggest other approaches to help boost your energy while your body gets used to the GLP-1 drug.

If you think you might have an infection or symptoms unrelated to your medication, get medical advice from a healthcare professional. They can help figure out what’s going on so that you get the right treatment.

Managing Your Energy While Taking GLP-1 Drugs

If you’re feeling more tired than usual while taking a GLP-1 medication, you can take steps to help boost your energy levels. Fatigue can be tied to other side effects of GLP-1 drugs, so you might feel better if you try to manage these symptoms:

• Nausea — Avoid strong smells, especially those associated with food. About half an hour after taking your medication, try settling your stomach by eating something small, such as mints, ginger (in tea or chews), or even crackers.
• Vomiting — Eat smaller meals more often so that your stomach never feels overloaded. Be sure to also monitor your hydration and get enough water.
• Diarrhea — Drink plenty of fluids. You might want to skip high-fiber foods and dairy until your symptoms improve.
• Appetite loss — Eating with friends or family may make meals more enjoyable. You can also work with a dietitian to help you find foods that appeal to you and give you the energy you need.

Other Ways To Manage Fatigue

Sometimes your body just needs time to adjust. In the meantime, these tips might help:

• Exercise regularly but not so hard that you feel exhausted afterward.
• Watch your use of alcohol, which can make fatigue worse. Guidelines from the National Center for Health Promotion and Disease Prevention suggest no more than two drinks a day for men and one drink a day for women or anyone over 65.
• Find ways to lower stress, which can drain energy. Journaling, talking with friends, or practicing relaxation techniques such as deep breathing may help reduce anxiety.
• Use caffeine carefully. Although caffeine can help boost energy levels, too much — or having it too late in the day — may interfere with your sleep.
• Drink plenty of water. Proper hydration helps your body work better so you feel more rested.
• Eat for energy, focusing on getting the nutrients you need without triggering symptoms. Choose low-glycemic carbohydrates, such as whole grains and vegetables, to keep blood sugar steady without making nausea worse.

Together, these management techniques can help you feel more like yourself again while your body adjusts to a GLP-1 agonist.

Check With Your Doctor About Tiredness and GLP-1 Drugs

If you’re feeling extra tired while taking a GLP-1 drug — or if you notice any other new or worsening symptoms — talk with your healthcare provider. Even small changes in how you feel could be related to your medication, and your doctor can help you figure out what’s going on.

If you haven’t started the medication yet but you’re worried about fatigue, tell your doctor. You can work together to make a plan in case tiredness starts to interfere with your daily life.

The best way to use GLP-1 medications is with support from a team of medical practitioners from different specialties. This might include your primary care provider, an endocrinologist (a doctor who treats hormone-related conditions), a dietitian, or a mental health professional. Together, they’ll help you manage side effects, support your healthy habits around eating and exercise, and guide you toward your best quality of life.

Talk With Others Who Understand

MyObesityTeam is the social network for people with obesity and their loved ones. On MyObesityTeam, more than 57,000 members come together to ask questions, give advice, and share their stories with others who understand life with obesity.

Are you taking GLP-1 drugs and feeling tired? Has this affected your everyday life? Share your experience in the comments below, start a conversation by posting on your Activities page, or connect with like-minded members in Groups.