Aromatherapy is the use of essential oils from plants (flowers, herbs, or trees) as a complementary health approach. The essential oils are most often used by inhaling them or by applying a diluted form to the skin. Many essential oils are used in aromatherapy, including those from Roman chamomile, geranium, lavender, tea tree, lemon, ginger, cedarwood, and bergamot.

Aromatherapy is sometimes used for insomnia, but we don’t know whether it’s helpful because little rigorous research has been done on this topic.

Aromatherapy is sometimes incorporated into massage therapy for various conditions, such as knee pain from osteoarthritis or pain, anxiety, and other symptoms in people with cancer.