Why is my arms and feet turning dark

Hello Anon

Thank you for writing.

You need to have a full evaluation to know what's going on. We can only offer a suggestion.

One suggestion is that it could be due to peripheral vascular disease - Peripheral vascular disease (PVD) is a general term for disease of any blood vessel that is not part of the heart or brain. The arterial form, usually referred to as PAD, is caused by deposits of fatty material (atheroma) in arteries of the legs. Since arteries carry oxygen-rich blood to the cells of the body, restriction of this blood flow can cause bodily organs to fail.
One symptom is discoloration of the skin.

Please contact your doctor.
Best,
Susan