Hi Emmanuel,
Thank you for the photographs. The areas you mention - hands, feet, penis and scrotum are naturally darker than the rest of the body. The reasons for this are different. The penis and scrotum are darker because they have a very rich blood supply and this makes the skin darker. No treatment is required or indeed effective here. The hands and feet are darker because of tanning and also racial pigmentation (acral darkening). This can be treated with measures I will detail below but pl ...
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