Yes, allergies can cause migraines
As if dealing with symptoms of seasonal allergies—runny nose, sneezing, watery eyes—wasn’t bad enough, here comes a migraine to ruin your day.
“If your allergies are poorly controlled, you can experience a headache, fatigue, and sinus pain and pressure. This can make a migraine feel worse,” says Tania Elliott, MD, a spokesperson for the American College of Allergy, Asthma, and Immunology (ACAAI) based in New York City.
Why allergies trigger migraines
When you have allergies, your body releases inflammatory molecules called histamines, which circulate in your blood, setting off symptoms like sneezing and watery eyes. “These molecules come from cells responsible for controlling the immune response, called mast cells. Mast cells are found throughout the body—and they also line the surface of the brain,” explains Wade Cooper, doctor of osteopathic medicine and director of the Headache and Neuropathic Pain Program at the University of Michigan in Ann Arbor, Michigan. “When they become active, they release inflammatory signals, such as histamines and CGRP [calcitonin gene-related peptide] that are known to activate migraine.”
Who’s at risk? If you have environmental or food allergies, odds are greater that you’ll have these types of migraines compared with people who don’t, Dr. Cooper says.
Is it a migraine or an allergy migraine?
There’s a little confusion here, and that’s understandable. First, migraines can cause watery eyes, stuffiness, and facial fullness, Dr. Cooper says, symptoms that often lead people to assume they have allergies. (If you think you have allergies, seeing a board-certified allergist to confirm your suspicions can help you go down the right path for treatment.)
That said, if you have known allergies and also experience migraines, the two might be related, Dr. Cooper adds, “because allergy and migraine use some of the same pathways to cause symptoms in your body.”
How a headache diary can help
To figure out if your allergies are a trigger for migraines, you can keep a headache diary.
Dr. Elliot suggests maintaining a headache diary for two weeks, recording your activities and diet as well as any headaches, facial pain or pressure, congestion, itchy eyes, and/or runny nose. She also advises completing the Rhinitis Control Assessment Test (RCAT) at least three times per week. But this isn’t something you need to figure out all on your own. “Meet with an allergist to review your diary and they will help you draw conclusions,” she says.
Signs you’re having an allergy migraine
Symptoms of an allergy migraine may overlap with those of a traditional migraine. (And they may feel like a sinus headache, too.) Here’s how to determine what’s going on:
You’re sensitive to light and sound
Allergies are linked to both migraines and sinus headaches, according to the ACAAI, but there are certain symptoms that can help identify a migraine. “A regular sinus headache should never be severe, cause you to feel nauseated, or make you sensitive to light or sound,” Dr. Cooper says. These are classic symptoms unique to migraines, not sinus headaches.
You get aura
An aura refers to sensory disturbances that precede some migraines, including seeing sparks, dots, or zig-zags that last 20 to 60 minutes, according to the American Migraine Foundation. If you have an aura, it’s more indicative of a migraine because a sinus headache is not known to cause this symptom, Dr. Elliott says.
Your nose is runny
If your nose is constantly runny, that may mean you’re more at risk for allergy migraines to begin with. “People who experience a constantly runny nose from allergies have a 10 times higher chance of having migraine sometime in their life,” Dr. Cooper says.
You have congestion
Though sinus headaches are more commonly associated with itching, a runny nose, and congestion, migraines can also cause a runny nose and watery eyes. Migraines are not usually associated with itching, however, Dr. Elliott says.
You feel facial pain
According to the ACAAI, facial pain localized around sinuses can be a symptom of either an allergy headache or a sinus headache. Up to 90 percent of sinus headaches are actually migraines, however, according to a 2016 study published in Current Neurology and Neuroscience Reports. In general, trying to treat a sinus infection is unlikely to help with a migraine problem. If you have migraines, there are other triggers in the environment—beyond allergies—that can lead to head pain.
Your headache is throbbing and one-sided
An allergy migraine and a migraine not triggered by allergies will both feature pulsating pain that may be (but isn’t always) located on one side of the head, notes the ACAAI. Understanding your triggers—more on that below—can help you figure out if allergies are the cause.
How to treat an allergy migraine
When you have an allergy migraine, you’ll want to treat both the migraine (for short-term relief) and the underlying allergies. Over-the-counter antihistamines can help reduce allergy symptoms, Dr. Cooper says, and “in some cases can lower headache frequency when used appropriately.”
As for treating migraines, talk to your doctor about the right migraine medication for you, as there are a variety of options, including over-the-counter pain relievers like ibuprofen, migraine-specific medications like triptans and ergots, and preventative medications such as antihypertensives, anticonvulsants, and antidepressants, according to the American Migraine Foundation.
The good news is you don’t have to choose whether to treat the allergies or the migraine—you can target both. “Most OTC medications for allergies and headache are safe to take together when used appropriately,” Dr. Cooper adds. If you have headaches more than four days per month, however, talk to your doctor, he advises. Frequently taking OTC meds like ibuprofen for headache relief can result in medication overuse headaches, which are headaches triggered by medication itself.
Preventing an allergy migraine
It’s all about managing your triggers. You may already deal with allergies by reducing exposure to allergens (such as keeping windows closed on high-pollen days, for example, or not mowing the lawn if you’re allergic to grass pollen), and that kind of adaptation can also decrease the risk of migraines, Dr. Cooper says. If you don’t know what your triggers are—they can be from environmental exposures or certain foods you’re eating, such as gluten or dairy—a headache diary may help you make those important connections.
Allergy immunotherapy may also be a long-term solution for preventing future allergy flares. This treatment exposes you to incremental doses of the allergen to help you build a tolerance to it. These are available as shots, tablets, and drops.