Itchiness under finger nails?

Infection/allergy?: This is a very unusual symptom, in fact i don't think i've ever had a patient with this problem! i did some research- the most likely cause is a fungal infection under the nail, a common problem that is usually not itchy, but the nail should look thick, distorted or discolored. It might also be a reaction to nail polish. It might also be an allergy to something you are eating. See my comment:.