Exploring the Impact of Subclinical Hypothyroidism on Hyperpigmentation: A Rare Presentation in a 42-Year-Old Woman.

Hyperpigmentation of the skin can occur due to internal and external causes. This case highlights an unusual presentation of generalized acute hyperpigmentation associated with subclinical hypothyroidism in a 42-year-old Indian American woman. After unsuccessful trials of various topical agents, the patient exhibited significant improvement in hyperpigmentation after levothyroxine treatment. Improvements included lightening in the bilateral antecubital fossa, axillae, and neck regions. This case underscores the importance of considering thyroid dysfunction as a potential factor that may contribute to atypical pigmentation disorders.