7 Causes of 'Brain Fog'

  • frustrated father paying bills online
    Likely Culprits, and What to Do About Them
    The term “brain fog” might not sound like a medical term. But it's a very real thing. It's a common way to talk about the memory problems, lack of focus, forgetfulness, and fatigue that come with some medical conditions and treatments. Here are seven common situations that can have brain fog as a side effect.

  • man-with-shoulder-pain
    Rheumatoid Arthritis
    Most people think of joint pain when it comes to arthritis. Medical experts, though, now know that conditions that cause chronic inflammation—like rheumatoid arthritis—often have another effect: They cause brain fog. Fortunately, the drugs that are good at treating rheumatoid arthritis also seem to help get rid of the symptoms of brain fog.

  • woman resting her head
    Some people with lupus have trouble with memory, thinking and expressing themselves. They can feel "foggy" and confused sometimes, too. One theory is that the disease affects blood flow to the brain, which is known to cause cognitive problems. Or, like rheumatoid arthritis, it could be linked to inflammation. Medications and counseling often help.

  • back spasm
    The most common symptom of fibromyalgia is chronic widespread pain. But, people who have it often complain of symptoms like forgetfulness, trouble with conversations, and short-term memory loss. Health experts aren’t quite sure why people with fibromyalgia suffer from brain fog. They suspect there's a link between chronic pain and how well the brain works. 

  • Fatigued Man
    Chronic Fatigue Syndrome
    Chronic fatigue syndrome affects millions of Americans. Though "fatigue" is in the name, feeling extremely tired is just one of many symptoms. People with this condition often have muscle and joint pain and problems sleeping. They also complain of brain fog—memory problems and trouble paying attention. In fact, researchers have noted people with chronic fatigue often identify this as the most troubling symptom.

  • athlete on stretcher
    Many causes of brain fog are somewhat mysterious. A concussion is a more obvious link. This is a head injury that directly affects the brain. Brain fog symptoms like confusion, slow thinking, memory problems, and trouble concentrating are common after a concussion. They usually get better over time. Repeated head injuries can make things worse, however. Always wear proper head protection during sports and other activities where head injuries are possible. And if you suspect a concussion in yourself or a loved one, get it checked out by a doctor to help minimize brain damage from a concussion.

  • male connected to medical equipment
    Medical conditions aren’t the only contributors to brain fog. Some medicines and medical treatments can cause this mental cloudiness, too. One of the major culprits is chemotherapy. In fact, the problem is common enough among cancer patients that it has its own name: “chemo brain.” It may go away quickly or linger awhile. How bad it is also varies from person to person. But, if you experience brain fog after chemotherapy, talk with your healthcare team because help is available.

  • Senior woman holding a bottle of pills
    Other Medications
    Many types of medicines can lead to confusion or fogginess. Antidepressants and anti-anxiety drugs may do this. So can drugs that lower cholesterol and blood pressure, sleep medications, Parkinson’s drugs, drugs that combat seizures, and very strong painkillers (narcotics). Even some older types of antihistamines can cause brain fog. Most often, the mental side effects go away once you stop taking the drug. Your doctor will want to know if you are experiencing these types of side effects from a medication, prescription or not. Ask your doctor if another option might work for you. 

7 Causes of 'Brain Fog'

About The Author

  1. Why Do Some People with Rheumatoid Arthritis Experience Brain Fog? Arthritis Foundation. http://blog.arthritis.org/rheumatoid-arthritis/rheumatoid-arthritis-brain-fog/
  2. Lupus. Cleveland Clinic. http://my.clevelandclinic.org/health/diseases_conditions/hic_Systemic_Lupus_Erythematosus?_ga=1.1291...
  3. Lupus and Brain Fog: How to Find Your Way. Cleveland Clinic. https://health.clevelandclinic.org/2013/11/lupus-and-brain-fog-how-to-find-your-way/
  4. Fibro Fog. Arthritis Foundation. http://www.arthritis.org/about-arthritis/types/fibromyalgia/articles/fibro-fog.php
  5. Beyond Tired. American Psychological Association. http://www.apa.org/monitor/2014/10/beyond-tired.aspx
  6. Concussions: How a Neuropsychologist Helps. American Psychological Association. http://www.apa.org/helpcenter/concussions.aspx
  7. About Lupus -- Thinking, Memory and Behavior. SLE Lupus Foundation. http://www.lupusny.org/about-lupus/fight-lupus-body-and-mind/thinking-memory-and-behavior
  8. Chemo Brain. American Cancer Society. http://www.cancer.org/treatment/treatmentsandsideeffects/physicalsideeffects/chemotherapyeffects/che...
  9. Drugs That May Cause Memory Loss. AARP. http://www.aarp.org/health/brain-health/info-05-2013/drugs-that-may-cause-memory-loss.html

Was this helpful?
Last Review Date: 2020 Sep 4
Explore Brain and Nerves
Recommended Reading
Next Up
  • Keeping your brain in shape has major lifelong benefits like enhancing your memory, building new synapses, and possibly helping delay the onset of illnesses like Alzheimer’s disease.
  • A neurologist treats disorders that affect the brain, spinal cord and nerves.  When you're facing serious conditions like stroke, Alzheimer's disease, multiple sclerosis, or ALS, it's critical to find the right doctor for you.
  • Your brain and its memory function depend on good blood flow and healthy nerves to work well. To keep your arteries and brain cells healthy, get regular exercise and eat a nutritious diet. And be sure to include these memory-boosting foods.
Answers to Your Health Questions
Trending Videos