Allodynia and Migraine: An Oft-Overlooked Side Effect

How understanding this little-known symptom of migraine can lead to better care

The primary pain associated with migraine is well-known and well-documented: for some it’s a sharp pain on one side of the head, for others it’s a diffused ache or a persistent burning sensation. But secondary migraine symptoms can cause unique pain experiences, including hypersensitivity to typically innocuous contact, like a light touch. That experience can be confusing to patients and even doctors. It’s called allodynia, and it can render simple tasks like resting your head on a pillow or pulling your hair back in a ponytail, into intolerable, excruciating experiences.

Allodynia can be frustrating and confusing for patients because it is widely misunderstood— which makes treating it a challenge for many healthcare providers. Getting an accurate diagnosis of allodynia can not only help a person living with migraine to seek the right resources that could help relieve their pain, it can also provide valuable insights into the nature of their unique headache experiences.

Commonly Occurring, Commonly Misunderstood

Dr. Richard Lipton, Director of the Montefiore Headache Center and a Professor of Neurology at the Albert Einstein College of Medicine, is one of the first doctors to fully grasp the symptoms of allodynia.

“Ordinary stimuli, ordinary life experiences that wouldn’t be painful outside the migraine attack, can be painful for up to two-thirds of people with migraine during attacks,” Lipton said. “During migraine attacks, people may report that taking a hot shower hurts on the side of the head, or putting their head on a pillow may be painful. Even the weight of an earring pulling down the ear can be painful, as can brushing your hair, or wearing your hair back in a ponytail.”

Allodynia is more common in people with frequent headache, and, once understood, can be used by patients and doctors to predict headache progression. Allodynia may be a sign that Episodic Migraine, characterized by fewer than 15 headache days per month, is at risk of progressing to Chronic Migraine, defined by headaches that occur 15 or more days a month, Dr. Lipton says.

Advantages of Understanding Allodynia

Recognizing and responding to signs of allodynia can lead to a better understanding of how your migraine manifests, which can help your doctor devise the best plan for treatment. Furthermore, if patients can treat allodynia early, Dr. Lipton says repeat attacks are less likely.

“People who develop allodynia as their headache evolves should treat early in the attack because medicines will work better before allodynia further develops,” he says. “The key thing is to use preventive measures, either behavioral or drugs to reduce headache frequency, and then, if you’re going to take an acute medication, do your best to take it early.”

Dr. Lipton’s research has shown that allodynia is a distinct, recurring component in the progression of a migraine attack, something that is only recently widely recognized. As the medical community improves its understanding of allodynia, it could guide headache research efforts towards a better understanding of migraine.

How to Talk to Your Doctor About Allodynia

“We often say migraine is more than just a headache,” Lipton says. “And when we say that, usually what we mean is that migraine is always associated with other features: sensitivity to light, sound, smell, nausea, vomiting, maybe auras. But migraine is more than just the headache in terms of the location of pain, as well. Many people with migraine have pain outside the head.”

Patients might not always equate pain outside the head with migraine, or know how to talk to their doctors about treatment. Lipton suggests framing the pain as something that hurts your ability to function, rather than something that just hurts.

“I think the single most important thing is to tell your doctor about how headache impacts your life,” he says. “Complaints of function elicit in doctors the impulse to treat, not to reassure. Complaints of pain primarily elicit an impulse to reassure. So I think the single most important communication message is tell your doctor how your headaches influence your life.”

Finding a doctor who specializes in headache or migraine can make it easier to find the right treatment for your unique symptoms and experiences, including allodynia. The American Migraine Foundation’s searchable database of headache specialists can help you find a doctor with expertise in treating migraine near you.