Psoriasis can affect more than your skin. It can also impact the health of your fingernails and toenails. It can cause pitting, abnormal nail growth, discoloration, and the nail to separate from the nail bed. What treatment works best for nail problems related to psoriasis is not well studied, according to the Annals of Rheumatic Diseases. However, if you have psoriasis, the following ideas may help keep your nails as healthy as possible.