What Is a Migraine?
No single test can diagnose migraines. But The International Headache Society (IHS) publishes criteria for what a migraine is (and isn’t). For instance, the IHS describes migraines without aura as recurring headaches that last up to 72 hours, with characteristics like pain on one side of the head, a pulsating quality, and moderate or severe pain intensity. Migraine symptoms may include nausea or photophobia (discomfort with bright lights).1
Although they’re less common, migraines with aura have visual symptoms like seeing geometric patterns, flashing lights or possibly a shimmering effect (kind of like heat waves) prior to a migraine striking. Less than one quarter of migraine patients will experience aura. Those who do often have visual impairment starting five to 60 minutes before a migraine strikes.1
Part 1: The Medical History
Doctors rely on two sources of information to fill in the blanks on a migraine diagnosis: your medical history and a physical exam. Your medical history provides the most complete view of your condition, say Elizabeth Seng, Ph.D., a clinical psychologist and headache researcher in New York City. It helps your doctor sleuth, sift through, and rule out other diseases with symptoms mimicking a migraine.2
When you talk to your doctor, you’ll be asked to provide as many details as you can about your symptoms, other medical conditions, family health issues, and your head pain history. “We want to know anything that’s ever happened with your brain,” says Dr. Seng.
You’ll also be asked about your personal habits, including diet and exercise, and may be requested to keep a migraine diary for one month. During this time, you’ll write down every time you have head pain and what it feels like, says Dr. Seng: Is the pain pulsing or pressing? On just one side of your head or both? Where does the pain start, and how severe is it on a scale of 1 to 10? Does your pain get worse with exercise? “This diary is really going to tell the doctor everything he or she needs,” says Dr. Seng. “When diagnosing migraines, we look for two of these four symptoms: severity, pounding or pulsing quality, one-sided pain, and pain that gets worse with physical activity.”2
Part 2: The Medical Exam
For the physical exam, the doctor may check your head and neck, and will usually do neurological exercises that test strength, reflexes, and sensation. You might also be tested for symptoms such as alertness, coordination, and gait, as well as short-term memory.3
Your doctor will likely ask you how long your headaches last, whether you feel nauseous or are vomiting, if you have sensitivity to light, and how disabled you might feel when you’ve got the headache—all part of the guidelines for a migraine diagnosis.1 In particular, expect questions about the location of the pain, since many times migraines involve throbbing pain on one side of the head.
A Process of Elimination
Why all the questions? Doctor want to rule out other types of head pain, such as sinus headaches and cluster headaches, as well as other potential causes. Red flags that something else is going on include fever, weight loss, runny nose, eye tearing or sudden onset of headaches. Doctors use a method called SNOOP to elicit whether any of these worrisome symptoms could be a sign of a serious health situation such as a brain aneurysm or brain tumors (see the American Headache Society for more). Your physical exam will include vital signs and simple neurologic tests to help rule out those possibilities. In the rare case that your doctor finds cause for concern, blood tests and/or imaging studies will be ordered to pinpoint the root cause, says Dr. Seng.
With a diagnosis in hand, your doctor can help you come up with a treatment program best suited to your needs. Treatments vary widely, according to migraine symptoms, frequency and severity as well as coexisting medical conditions.4 Your solution will likely involve some form of medication, either in prescription or over-the-counter form, along with adjustments to your daily routine and lifestyle.