Shaving, waxing, or excessive sweating can cause dark underarms and bikini lines for you. you need to try some home remedies like potato, which works as a natural bleaching agent. It works as a natural bleaching agent and very effective for underarm whitening skin
1-Potato Slices for whiten underarms
2 Cut a thick slice of potato and rub the affected area for 15 minutes
Let it dry for almost an hour and wash it off with lukewarm water.
Grate a two potato and squeeze their juice
Apply it to your underarms for 15 minutes
Rinse your armpits with cool water after the prescribed time.
If you are concerned about the skin of your underarms being darker than the skin on the rest of your body, you must discuss this situation with your doctor.
If your dark underarms are not the result of an underlying condition needing medical treatment, talk with your doctor about some of the alternatives for lightening underarms.