If you’ve ever been around someone who smells like they bathed in cologne, you’ll be very aware that some scents can make your head pound. (Personal flashback: Getting hotboxed by Acqua Di Gio in a high-school driver’s ed car.) But it turns out that sniffing essential oils for headaches can have the exact opposite effect.

“Essential oils can help alleviate headaches a few different ways,” says chemist and pharmacist Lindsey Elmore, PhD. Some of these benefits are physical. “They may relax certain muscles around the neck, face, and head to help relieve tension that can trigger headaches. They also may induce a significant increase of blood flow to the forehead after local application,” she explains. Essential oils may also help “block pain transmission, desensitize pain fibers, and reduce inflammation,” adds neurologist and headache specialist Sara Crystal, MD—a board-certified neurologist and medical advisor for migraine treatment startup Cove.

But there may also be a mental component to using essential oils for headaches, says Dr. Elmore. “The aromas of essential oils help to release emotional blockages and can be calming to the mind,” she says. (Helpful if your headache is caused by an overly chatty coworker or an energy-vampire sibling.)

So why do I have a headache in the first place?

It’s fitting that essential oils attack headaches from so many different angles, because the condition is extremely complex. According to Drs. Elmore and Crystal, there are a ton of reasons why you might have one in the first place. These include:

• Dehydration
• Poor sleep
• Drinking alcohol
• Allergies
• Hormone changes
• Stress
• Certain prescription or over-the-counter medications
• Sinus congestion
• Weather
• Excess caffeine (or too little, if you’re addicted)
• Bright lights (or the light from your digital devices)

There are almost as many types of headaches as there are triggers—over 150, according to the International Headache Society. And not all of them respond to essential oils. “Tension-type headaches and migraines tend to be more responsive to essential oils than other types of headaches are,” says Dr. Crystal. This is because essential oils are particularly good at combatting symptoms of stress, says Dr. Elmore—a major cause of both tension headaches and migraines.

Also: If you’re experiencing headaches that are more frequent or severe than usual, or keep you from doing normal activities, you should get them checked out by a doctor before exploring alternative remedies. And if you’ve got a headache and are confused, vomiting, numb or weak on one side, experiencing a high fever or stiff neck, or are having trouble seeing, speaking, or walking, get yourself to the ER, stat.

Which essential oils are best for headaches?

1. Peppermint oil: Is there anything this super-fresh-smelling oil can’t do? It’s said to helps you conquer PMS, overcome the 3 p.m. slump, and—yes—even ward off a headache. The secret is in its menthol content, say the doctors. “Menthol can generate a cooling effect on the skin, which can relieve some headaches,” says Dr. Elmore. “One small study showed that applying topical menthol 6% gel showed a significant improvement in headache intensity, which suggests that it could be an effective acute treatment,” Dr. Crystal adds.

2. Lavender oil: If your headaches happen most often when you’re stressed or can’t sleep, this one’s for you. “One small study shows that inhaling lavender is effective for relieving stress, promoting sleep, and alleviating symptoms of migraine headaches,” says Dr. Elmore. Yep, she said migraine headaches—the most severe of all.

3. Rosemary oil: Dr. Crystal says that this anecdotal hair-growth remedy may also be effective for headaches. She refers to an animal study that showed a reduction of pain and inflammation in test subjects after they were treated with rosemary essential oil. More research is needed since it was on animals, but still…promising!

4. Oregano, thyme, and mountain savory: These three oils all have one thing in common, says Dr. Elmore: a compound called carvacrol. (Peppermint oil has it too, FYI.) “This chemical constituent has been shown to be effective at alleviating some types of headaches,” she says—it may block pain signals, according to several animal studies.

What’s the best way to use essential oils for headaches?

When it comes to actually using essential oils, say the doctors, you’ve got options. If you’re out and about, the easiest thing to do is inhale it. Dr. Crystal recommends placing a few drops of the oil into a tissue and breathing into it. If you’ve got a carrier oil at hand, like coconut oil, Dr. Elmore says you can mix the two and massage it into your temples or forehead. For those times when you need a little extra reinforcement, Dr. Crystal suggests “placing a few drops of oil onto a hot or cold compress and applying it to your forehead.”

Are there any risks to using essential oils for headaches?

Generally, essential oils are fairly safe. But be mindful not to directly apply any essential oil to your skin, because that can cause irritation. (Never, ever skimp on that carrier oil!) You should also avoid using essential oils around your eyes, says Dr. Crystal, since they can burn. If you have sensitive skin, it’s a good idea to spot test a small amount of the diluted essential oil on a small patch of skin and see if it causes a reaction—since some people can react even to essential oils mixed with a carrier.

You should also make sure you’re buying the purest oils possible, adds Dr. Elmore. “Many oils sold over-the-counter are adulterated by solvents and extenders, or even altered entirely,” she says. “It is so important that the oil you use comes from the whole plant and is unaltered with nothing added and nothing taken away. There is a synergistic effect among all components within every plant that help support the primary therapeutic functions of the botanical.” Because when it comes to headaches, we need all the therapeutic juju we can get.

Did you know you can also use essential oils to clean your yoga mat and treat your hangnails?