Ingrown hair cysts occur when trapped hair causes red, swollen bumps, often from clogged pores. They are typically harmless and go away with home remedies. What Does an Ingrown Hair Cyst Look Like? An ...

Also known as a pilonidal cyst, the condition forms when a sac of tissue fills with air or fluid in the crease of your buttocks. Pilonidal cyst, doctors say, is mostly caused by a skin infection.