What causes ingrown hairs?
Ingrown hairs have usually grown out of the skin, curled back round and re-entered the skin.
Some curl back into the hair follicle – small cavities in the skin that hairs grow out of – without even exiting the skin.
An ingrown hair can occur when the hair follicle becomes clogged with dead skin cells.
This forces the hair inside it to grow sideways, which is much more likely to happen if the hair is already curly or coarse and it's recently been shaved.
Ingrown hairs can be a particular problem in areas where you may shave – such as the beard area in men, and the legs, armpits and pubic area in women.
In these places, the hair that grows back has a sharper edge and can easily poke back into the skin.
Ingrown hairs look like pimples in the skin, and sometimes you can see the hair trapped beneath the skin. The spots can be filled with pus.