Causes
Causes include:
- Blockage of a hair follicle by skin cells—When an injury to the skin occurs, cells from the surface may block hair follicles located deeper within the skin.
- Damage to a hair follicle due to acne
- Blockage or defect of the sebaceous gland—This gland is near the hair follicle. It secretes oily material used to lubricate the skin and hair.
Hair Follicle

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