Ozempic Brain Fog

Mike Chi

Reviewed by Mike Bohl, MD

Written by Lauren Panoff

Published 06/05/2024

Glucagon-like peptide-1 receptor agonists (GLP-1s) like Ozempic® (semaglutide) and Wegovy® (semaglutide) have gained popularity for their effectiveness in supporting blood sugar control in those with diabetes and weight loss in those with obesity.

With more people using weight loss drugs with the active ingredient semaglutide, there are more conversations about individual experiences. For instance, more people are comparing notes about side effects like brain fog.

Does using Ozempic cause brain fog? It depends on who you ask. We took a closer look at what’s going on with Ozempic users reporting brain fog, including how the medication works in the brain and what the drug packaging says about side effects.

If you’re on social media platforms like TikTok and Reddit, you may have seen trending conversations about Ozempic and brain fog.

Some Ozempic users describe the experience as going “into a zombie state” or feeling “groggy and forgetful,” which they say can last for a few weeks or a few months depending on the person.

While reports should be taken seriously, the majority of evidence behind the relationship between taking Ozempic and experiencing brain fog is anecdotal.

It’s difficult to investigate the science behind what may be happening because research on this topic is lacking.

But for all intents and purposes, if people are reporting experiencing brain fog when using Ozempic, we’re not going to argue with them. Instead, we looked into some of the reasons why this could be happening.

GLP-1s affect the brain's reward center by influencing the activity of neurotransmitters and signaling pathways involved in appetite regulation.

They interact with GLP-1 receptors in key regions of your brain, including the hypothalamus and the mesolimbic system, which are crucial for hunger and reward processing.

Here, GLP-1s help regulate energy balance by promoting satiety, which can lead to less food intake. They also reduce the rewarding effects we feel when eating certain types of food, especially highly palatable and high-calorie foods.

This, in turn, helps reduce cravings and the desire to eat said foods, ultimately reducing calorie intake and supporting weight loss.

Because GLP-1s directly target the brain in these ways, brain-related side effects aren’t unreasonable.

While we may not have scientific evidence about brain fog specifically, there are other documented brain-related side effects of using Ozempic. For instance, some people report an increase in odd, vivid dreams when using it.

GLP-1 users also report both improvements and deteriorations in their mood, sleep quality, and feelings of anxiousness.

While some people experience antidepressant effects, some have reported the opposite. There are concerns about the risk of depression, anxiety, and suicidal thoughts linked to these weight loss medications. More research on mental health effects is needed.

On the other hand, emerging research suggests GLP-1s may offer protective benefits for your brain. For example, some limited research suggests using GLP-1s may help prevent cognitive decline and neurodegenerative conditions like dementia in certain populations.

Either way, there appear to be things going on between GLP-1s and the brain that we don’t fully understand yet.

Ozempic and Food Noise

The phrase “food noise” refers to constant intrusive thoughts about food and constant food cravings. People who experience food noise report feeling extremely preoccupied with thoughts about eating, meals, snacks, and specific foods, even when they're not particularly hungry.

You know that saying, “Whether you think you can, or you think you can’t, you’re right”? In other words, what you focus on becomes your reality.

In the context of food noise, this kind of mental distraction can lead to overeating, making poor food choices, or difficulty resisting ongoing urges to eat certain things.

Many people report regularly experiencing food noise, which can be a significant barrier to any weight loss journey. People who are trying to lose weight are especially excited about Ozempic for this reason: GLP-1s like Ozempic can help reduce food noise by acting on your brain’s appetite and reward centers.

Interestingly, one study even found that GLP-1s can have anti-addiction effects related to drug, alcohol, and tobacco use disorders.

These mechanisms are not yet well understood, but researchers think they could involve how GLP-1s influence the signaling of dopamine, a brain chemical involved in feelings of motivation, pleasure, and satisfaction. This could also be relevant to food cravings.

Ozempic users who say the medication turns off food noise also say their cravings return once they stop using it. This is why it’s important to acknowledge that Ozempic isn’t a magic fix for the underlying obstacles involved in weight management.

Prescribed online

Weight loss treatment that puts you first

While Ozempic can be very effective for weight loss, especially when combined with other lifestyle habits like good nutrition and exercise, not everyone responds how they hope. Also, it’s important to note that Ozempic isn’t specifically FDA approved for weight loss, but healthcare providers can prescribe it off label for this purpose at their discretion.

Ozempic has potential side effects that are important to know about before using it.

Extensive studies demonstrate that most semaglutide side effects are mild, temporary, and related to the digestive system. And according to the Food and Drug Administration Ozempic package insert, the most common side effects of Ozempic — reported in five percent or more of users — are nausea, vomiting, diarrhea, abdominal pain, and constipation.

Others can include:

  • Reduced appetite

  • Fatigue

  • Dizziness

  • Headache

  • Acid reflux

  • Injection site reactions (redness, swelling, or itching)

More serious and rare potential side effects may also occur. These include:

  • Pancreatitis (inflammation of the pancreas)

  • Hypoglycemia (especially when used with other diabetes medications)

  • Kidney problems, including acute kidney injury

  • Gallbladder disease, including gallstones

  • Allergic reactions (rash, itching, swelling, severe dizziness, trouble breathing)

Ozempic may also increase the risk of thyroid tumors called medullary thyroid carcinoma. Additionally, there’s a possibility that people who have diabetic eye disease will have a higher risk of diabetic retinopathy complications on this drug.

Because discussions about Ozempic and brain fog are fairly common, we rounded up some related FAQs.

Does Ozempic Affect Your Mood?

Ozempic may affect your mood. While its primary function is to manage blood sugar levels, some people report mood changes, like feelings of anxiousness or depression.

This may be due to the medication's effects on the central nervous system or as a secondary result of changes in diet and weight. More research is needed to better understand the connection between Ozempic and mental health.

Does Ozempic Cause Memory Loss?

There’s no strong evidence to suggest that Ozempic causes memory loss. While GLP-1s primarily target blood sugar regulation and appetite control, their effects on brain function are still being studied.

Some research even indicates they may offer protective benefits for the brain, which could positively impact memory and cognitive health rather than impair it. We know we sound like a broken record here, but more research is needed.

Is Ozempic Safe?

Ozempic is considered safe for most people when used as prescribed, but it has potential side effects. It’s important to use Ozempic under the supervision of a healthcare professional and alert them if you experience anything unexpected.

Semaglutide brain fog isn’t an uncommon complaint among those using it to support their weight loss goals. Rather than definitively saying it’s an Ozempic side effect or not, we believe reports of those experiencing it and are interested in what future research uncovers.

  • Ozempic is active in the brain. Brain-related side effects make sense considering GLP-1s target the brain reward pathways. We just don’t fully understand how this may relate to fogginess or forgetfulness yet.

  • There are other options. If you’re using Ozempic and experience brain fog or related side effects that are concerning to you, know that you can try something else. In addition to healthy lifestyle habits like nutrition and movement, you can discuss other weight loss medications with your healthcare provider.

  • Mental health matters. Regardless of whether you’re experiencing brain fog from using Ozempic, if your mood is suffering we encourage finding a therapist. Getting the mental health support you need is essential for your weight loss success and overall quality of life.

Are you interested in connecting with one of Hers’ affiliated licensed medical providers? We’d love to help! Start by taking our free online weight loss assessment.

10 Sources

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  2. Canadian Agency for Drugs and Technologies in Health. (2019). Clinical Review Report: Semaglutide (Ozempic): (Novo Nordisk Canada Inc.): Indication: For the treatment of adult patients with type 2 diabetes mellitus to improve glycemic control, in combination with metformin (second-line treatment), and in combination with metformin and sulfonylurea (third-line treatment). https://www.ncbi.nlm.nih.gov/books/NBK544009/
  3. Food and Drug Administration. (2017). Highlights of Prescribing Information: Ozempic. https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/209637lbl.pdf
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  7. Mahapatra MK, et al. (2022). Therapeutic potential of semaglutide, a newer GLP-1 receptor agonist, in abating obesity, non-alcoholic steatohepatitis and neurodegenerative diseases: A narrative review. https://pubmed.ncbi.nlm.nih.gov/35650449/
  8. Nørgaard C, et al. (2022). Treatment with glucagon-like peptide-1 receptor agonists and incidence of dementia: Data from pooled double-blind randomized controlled trials and nationwide disease and prescription registers. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8864443/
  9. Reddit. (2022). Does brain fog ever go away? https://www.reddit.com/r/Ozempic/comments/w3yki9/does_brain_fog_ever_go_away/?rdt=58183
  10. Smits M, et al. (2021). Safety of semaglutide. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8294388/
Editorial Standards

Hims & Hers has strict sourcing guidelines to ensure our content is accurate and current. We rely on peer-reviewed studies, academic research institutions, and medical associations. We strive to use primary sources and refrain from using tertiary references. See a mistake? Let us know at [email protected]!

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.

Mike Bohl, MD

Dr. Mike Bohl is a licensed physician, a Medical Advisor at Hims & Hers, and the Director of Scientific & Medical Content at a stealth biotech startup, where he is involved in pharmaceutical drug development. Prior to joining Hims & Hers, Dr. Bohl spent several years working in digital health, focusing on patient education. He has also worked in medical journalism for The Dr. Oz Show (receiving recognition for contributions from the National Academy of Television Arts and Sciences when the show won Outstanding Informative Talk Show at the 2016–2017 Daytime Emmy® Awards) and at Sharecare. He is a Medical Expert Board Member at Eat This, Not That! and a Board Member at International Veterinary Outreach.

Dr. Bohl obtained his Bachelor of Arts and Doctor of Medicine from Brown University, his Master of Public Health from Columbia University, and his Master of Liberal Arts in Extension Studies—Journalism from Harvard University. He is currently pursuing a Master of Business Administration and Master of Science in Healthcare Leadership at Cornell University. Dr. Bohl trained in internal medicine with a focus on community health at NYU Langone Health.

Dr. Bohl is Certified in Public Health by the National Board of Public Health Examiners, Medical Writer Certified by the American Medical Writers Association, a certified Editor in the Life Sciences by the Board of Editors in the Life Sciences, a Certified Personal Trainer and Certified Nutrition Coach by the National Academy of Sports Medicine, and a Board Certified Medical Affairs Specialist by the Accreditation Council for Medical Affairs. He has graduate certificates in Digital Storytelling and Marketing Management & Digital Strategy from Harvard Extension School and certificates in Business Law and Corporate Governance from Cornell Law School.

In addition to his written work, Dr. Bohl has experience creating medical segments for radio and producing patient education videos. He has also spent time conducting orthopedic and biomaterial research at Case Western Reserve University and University Hospitals of Cleveland and practicing clinically as a general practitioner on international medical aid projects with Medical Ministry International.

Dr. Bohl lives in Manhattan and enjoys biking, resistance training, sailing, scuba diving, skiing, tennis, and traveling. You can find Dr. Bohl on LinkedIn for more information.


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