Oily hair is the result of the oil (sebaceous) glands in the scalp producing large amounts of oil.
Hair - oily; Greasy hair
Here are some tips for preventing and treating oily hair:
Hormones affect oil production. Things that affect your hormone levels (such as stress or birth control pills) may also affect the oiliness of your hair.
American Academy of Dermatology Association website. Tips for healthy hair. www.aad.org/public/everyday-care/hair-scalp-care/hair/healthy-hair-tips. Accessed December 12, 2022.
Dinulos JGH. Hair diseases. In: Dinulos JGH, ed. Habif's Clinical Dermatology. 7th ed. Philadelphia, PA: Elsevier; 2021:chap 24.