There is darkening of the skin follicles in the armpit region. I would then ask if you remove the armpit hair regularly and whether you get irritation or infection of the follicles of the skin after removal.
If that is the case, it could be a case of darkening of the skin secondary to inflammation from the hair removal process - called post-inflammatory hyperpigmentation.
Treatment -
- Stop regular hair removal. One can consider permanent hair removal with long-pulsed Nd:YG laser.
- Pigment lightening creams are useful but again beware of the irritation of some types of creams.
- Superficial chemical peels at monthly intervals will lighten the pigmentation.
I hope you have found this useful.
Thank you.
Regards,
Dr Benjamin Yim Fu Chuen