What are underarm dark marks?
Underarm dark marks are darker patches of skin in the underarm area. This is called post-inflammatory hyperpigmentation and is the result of a protective response from skin to irritation.
What causes them?
When removing underarm hair – by shaving, plucking and waxing – your skin becomes irritated. It may react by producing an extra pigment, called melanin, which can lead to the appearance of dark marks on your underarm skin. Every time you remove underarm hair, the cycle starts again. Not everybody’s skin reacts the same way and women with more sensitive skin types may produce more melanin in response to irritation.