Nail changes in psoriasis are very varied.

Some systemic diseases or drugs may cause increased pigmentation that can affect the nails. Brownish discolouration of the last two toenails of both feet may be a result of friction within the shoe. Pigmented bands along the length of the nail may be seen in dark-skinned individuals, or may be due to a mole arising from the nail fold region.

Rarely, a pigmented band may be due to melanoma, a form of skin cancer. Suspicious features include the band appearing in a previously normal nail becoming wider and darker or damaging the nail.

They may appear as pits on the nail plate. The nail plate may be separated from the nail bed (onycholysis). The nail may lose its normal luster and appear discoloured. Gross thickening of the nail is another feature of psoriasis. Typical psoriasis rash would often be present on the fingers, toes and elsewhere on the body.