A US government report out this month finds that more than 3 million Americans pounded emergency rooms with headache complaints in 2008. The ER For a headache, you say? “They may have already tried over-the-counter painkillers or they may be in severe pain and their physician is not readily available,” explains Seymour Diamond, M.D., executive chairman of the National Headache Foundation.

More than 60 percent of the headaches were “type not specified.” Many of the headaches in the unspecified category may have been undiagnosed migraines and tension headaches—the most common types that are also tricky to diagnose—says Dr. Diamond. Here’s how to tell the difference, and what to do about them.

It’s a Migraine
RECOGNIZE IT: About 1 in 5 migraines start with an “aura”—changes in vision (wavy lines, dots, flashing, blind spots), smell, taste, touch (pins-and-needles sensation) or even hallucinations. Then a migraine typically progresses from a dull ache into a throbbing or pulsating pain focused on one side of the head at the temples, front, or back. Nausea, vomiting, and sensitivity to light and noise are also common. It can last anywhere from 4 to 72 hours.

TREAT IT: When a migraine strikes, try one of the FDA-approved OTC migraine meds: Advil Migraine or Motrin Migraine Pain (both ibuprofen medications) or Excedrin Migraine (a combination of aspirin, acetaminophen, and caffeine). Once you’re feeling better, see a migraine specialist—not just your GP, Dr. Diamond stresses. A migraine is technically a neurological syndrome and can be tricky to diagnose and treat, he explains. Try the Migraine Research Foundation’s list of physicians certified in headache medicine by state.

It’s a Tension Headache
RECOGNIZE IT: A tension headache is just what it sounds like—often the result of stress, anxiety, fatigue, or anger. A tension headache typically feels like a pulling, pressing, or contracting sensation on both sides of the head at the temples or tightening around it. It can last for minutes or days.

TREAT IT: Take some aspirin, Advil, Tylenol, or Aleve, and then take a break from whatever is stressing you and find a way to relax for a while, the National Headache Foundation recommends.

And now for the serious stuff: For any type of headache, call 10111 or go to an urgent care centre if you notice the following symptoms. They could be a sign that you are suffering a stroke or another major problem:

  • Your headache feels like the worst you’ve ever had
  • You have speech, vision, or movement problems or you lose your balance
  • Your headache gets worse if you lie down
  • Your headache starts very suddenly.