You may have seen posts on social media or heard from friends about the benefits of essential oils.

They’re marketed as a natural way to reduce or eliminate some medical issues, such as migraines or nausea, and treat other issues like anxiety, high blood pressure, depression and inflammation. But do they actually work?

“There isn’t a lot of conclusive research that shows that using essential oils — such as using lavender oil to relax — work from a medical perspective,” said Susan Werner, MD, family medicine physician at Geisinger Nanticoke.

Essential oils are extracted from leaves, roots, bark, herbs or flowers and mixed with oil or alcohol. They can be applied directly to the skin, either on an abnormality or at the site of pain, for example, or on the bottoms of feet or the chest. They can also be diffused and inhaled — this is sometimes called aromatherapy.

Common essential oils such as lavender, tea tree, peppermint and rosemary are used daily to treat various ailments.

“The act of massaging oil into skin can be relaxing, and scents can be pleasant, but this doesn’t necessarily mean they are actually curing a medical problem or treating an ailment,” said Dr. Werner. “You might feel better because the massage relaxes you and you expect to feel better — this is a placebo effect.”

In studies where essential oils were found to provide medical benefit, researchers note a medical benefit could be attributed to several factors, not just essential oils. Most studies conclude that more research is needed.

“If you’re thinking about using essential oils or aromatherapy to treat a medical condition, you should definitely talk to your doctor first,” said Dr. Werner. While most people don’t have an adverse reaction to essential oils, they’re not for everyone. 

Some oils have caused skin rashes, inflammation and other allergic reactions.

“Essential oils can include volatile organic compounds (VOCs) that can irritate your eyes, throat or lungs,” said Dr. Werner. 

Children shouldn’t use essential oils, and people with chronic medical conditions should talk to their doctor before trying an alternative treatment. People with asthma, skin conditions or particularly sensitive skin, and pregnant or breastfeeding women should also avoid using essential oils without first talking to a doctor.

If you’re interested in trying an essential oil, try testing it out first.

“Apply a small amount of oil behind your ear for a few days and monitor it for any skin irritation before using the oil regularly,” said Dr. Werner.