You’ve been staring at the computer for hours. You’ve worked late all week and have in-laws coming this weekend. You have a raging case of PMS. Eyestrain, stress, and hormonal shifts are fairly common causes of headaches, which afflict 45 million Americans (most of them women). But sometimes the usual suspects don’t explain that pain in your head. That’s because some triggers are just plain weird—like perfume, storms, earrings … or even orgasms. Here’s how to identify the source of your headache so you can send it packing.

Perfume
“Strong scents bother me instantly,” says Bethany Hegedus, 35, a writer and receptionist from Brooklyn, New York. She can get a headache from a whiff of Lovely by Sarah Jessica Parker or a stroll past a Yankee Candle. Her sense of smell is so acute that she can sniff out whether a co-worker has changed laundry detergents or hand lotions, a degree of sensitivity common among scent-driven headache sufferers. The headaches can be fleeting if exposure is brief—or they can last all day.

Why it hurts: Strong odors may activate the nose’s nerve cells, which stimulate the nerve system associated with head pain. Ironically, the offending scents are often pleasant, says Vincent Martin, MD, a headache specialist at the University of Cincinnati College of Medicine.

What to do: Avoid perfumes, strong household cleansers, fragranced soaps and shampoos, and air fresheners. That’s a challenge when just about everything these days is “Clothesline Clean” or “Citrus Fresh,” but Hegedus does her best with unscented laundry detergent and deodorant, and wears no fragrances. At the office, she politely asks colleagues not to wear heavy perfumes. And if all else fails? “I keep a bottle of Excedrin Extra Strength at my desk,” she says.

That remedy has aspirin, acetaminophen, and caffeine, a combination endorsed by several medical organizations for migraine and tension headaches. However, you might want to try aspirin or acetaminophen individually rather than mixed together with caffeine, says Andrew Charles, MD, director of the Headache Research and Treatment Center at the University of Calofirnia, Los Angeles, School of Medicine.

Frequent use of medicines with caffeine can lead to dependency and “rebound” headaches, the kind that come right back as soon as the meds wear off. Aspirin, ibuprofen, and naproxen treat pain and the inflammation often associated with headaches. Acetaminophen fights pain, but not inflammation. (Another caveat: If over-the-counter meds don’t help, a trip to the neurologist may be needed, Martin says.)

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