|Other names: Onychoschizia, brittle nails|
|Symptoms||Separation of layers of nail tips, los splits|
|Causes||Frequent hand-washing, manicures, nail polish and remover, nail biting, repeated trauma|
|Diagnostic method||Appearance, blood tests|
|Prevention||Avoid repeated trauma|
|Treatment||Apply moisturiser, discontinue nail cosmetics, supplement vitamin deficiencies|
Nail splitting, also known as onychoschizia, is splitting of the free-edged tip of the nail. There is also often a longitudinal split in addition to the separation of keratin layers.
Frequent hand-washing is the usual cause, but it is also part of normal ageing. Manicures, nail polish and remover, nail biting, and repeated trauma such as typing, can contribute to nail splitting. Dehydration likely plays a role. Nutritional deficiencies that can result in nail splitting include iron, selenium, and zinc. Some skin diseases such as psoriasis and lichen planus may feature such nails.
Diagnosis is by its appearance, but sometimes blood tests are required to look for iron deficiency, thyroid problems, and kidney problems.
Treatment is by discontinuing nail polish and applying moisturiser. An acceptable alternative is gel nails. Some favourable response has been reported with biotin, at a dose of 2.5mg daily for 6-months, if the person is deficient in vitamin B7. It is not routinely given.
It is common among women and occurs in almost a third of newborns.
It also occurs in hooved animals such as horses.
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 Sloan, Brett (2022). "16. Multiple nail: nail splitting". In Waldman, Reid A.; Grant-Kels, Jane M. (eds.). Dermatology for the Primary Care Provider. Philadelphia: Elsevier. pp. 277–278. ISBN 978-0-323-71236-1. Archived from the original on 2022-04-16. Retrieved 2022-04-15.
- ↑ 2.0 2.1 2.2 2.3 Johnstone, Ronald B. (2017). "2. Diagnostic clues and "need-to-know" items". Weedon's Skin Pathology Essentials (2nd ed.). Elsevier. p. 31. ISBN 978-0-7020-6830-0. Archived from the original on 2021-05-25. Retrieved 2022-04-15.
- ↑ 3.0 3.1 3.2 3.3 James, William D.; Elston, Dirk; Treat, James R.; Rosenbach, Misha A.; Neuhaus, Isaac (2020). "33. Diseases of the skin appendages". Andrews' Diseases of the Skin: Clinical Dermatology (13th ed.). Edinburgh: Elsevier. p. 785. ISBN 978-0-323-54753-6. Archived from the original on 2022-04-16. Retrieved 2022-04-14.
- ↑ Colombo, Victor E.; Gerber, Françoise; Bronhofer, Max; Floersheim, George L. (December 1990). "Treatment of brittle fingernails and onychoschizia with biotin: Scanning electron microscopy". Journal of the American Academy of Dermatology. 23 (6): 1127–1132. doi:10.1016/0190-9622(90)70345-i. PMID 2273113.