When you’re rubbing your itchy eyes and sneezing your way through an allergy flare-up, do you also feel muddled and fuzzy-headed sometimes? Many allergy sufferers describe an experience known as “brain fog” — a hazy, tired feeling that makes it difficult to concentrate.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
What is this phenomenon and why does it happen?
According to allergist and immunologist Mark Aronica, MD, that disconnected feeling is fatigue, and it’s caused by the inflammation that results when your body tries to counteract your allergy symptoms.
“People with allergies experience inflammation,” he says. “That inflammation leads to a congested nose, disrupted sleep patterns and not getting good rest.”
And, once the cycle starts, it’s often a downward spiral. It seems like the more you rub your itchy eyes, the itchier they become! It can feel next to impossible to go on with your daily routine.
The more fatigued you are, the more difficulty you’ll have performing well in school or work. It can also negatively impact your quality of life if you’re too tired to do things you would normally do, like workout.
What’s really happening?
“Your body produces what’s called cytokines whenever you’re exposed to an allergen, such as tree pollen, grass or mold,” Dr. Aronica says. Part of your body’s immune response, cytokines are proteins that help your body fight foreign substances. “You also produce them when fighting infections caused by bacteria, viruses and colds,” says Dr. Aronica.
The cytokine release causes inflammation in your nose, leading to congestion and narrowed airways.
“Chronic inflammation from allergies can lead to that foggy feeling,” he says. “And, you’ll end up not functioning well.”
Fighting the fog
If your allergies act up and you feel the fog rolling in, there are a few things you can do to stop the uncomfortable cycle of symptoms, inflammation and fatigue, Dr. Aronica says.
1. Limit your exposure. “If you’re allergic to pollen or grasses, do your best to stay away from them,” Dr. Aronica says. Stay indoors when they’re at their peak. Keep your windows closed if you have air conditioning. If you do spend time outside for longer periods, take a shower and change your clothes right away when you come in.
But it’s often not feasible or realistic to stay indoors all the time. In that case, it’s important to take your medicine.
2. Take your medicine. Medication can help curb your allergy symptoms. Oral antihistamines — medications that prevent you from responding to the histamines that cause inflammation — are readily available over-the-counter. “They’re a temporary solution, but they are often effective,” says Dr. Aronica.Additionally, over-the-counter and prescription steroid nasal sprays can also help combat your allergy symptoms, Dr. Aronica says.
3. Get allergy shots. Allergy shots, or immunotherapy, is also an effective treatment. Small injections of allergens under the skin can help your body build up an immunity over time. The result is less frequent and less severe allergic rhinitis, Dr. Aronica says.
He adds that some allergy sufferers also find relief with nasal irrigation — a saline wash that cleans out the sinuses and nasal passages. Many people administer this type of wash with a neti pot to clear out lingering allergy symptoms. Just be sure to clean it after every use, given COVID-19 concerns.
Dr. Aronica notes that other conditions besides allergies may cause fatigue and brain fog. If you have a sore throat, cough, fever or body aches, you could have a cold or other illness and should take medications that will combat those symptoms. If you’ve been exposed to COVID-19 recently, contact your doctor.
To learn more about allergies from Dr. Aronica, listen to the Health Essentials podcast episode “Dealing with Spring and Summer Allergies.” New episodes of the Health Essentials podcast publish every Wednesday.