CARP and #acanthosisnigricans are often very similar in appearance and can both affect the neck and axilla. Not clear exact cause: It can be hereditary; Diabetes and PCOS + abnormal response to skin bacteria and yeast. NOT Contagious! Topical antifungal shampoos, retinoids can offer some relief but most effective are courses of oral antibiotics. Have you seen this? . . . . . #skinhyperpigmentation #darkarmpits #skinhacks #skincaretips #unevenskintone #dermatitis #dermatology