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URL of this page: //medlineplus.gov/ency/imagepages/2008.htm
Koilonychia
Overview
Nails may exhibit many different abnormalities. In the condition known as koilonychia, the nails are flattened and have concavities. This condition may be associated with iron deficiency.
Review Date 6/3/2025
Updated by: Ramin Fathi, MD, FAAD, Director, Phoenix Surgical Dermatology Group, Phoenix, AZ. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
