A Answers (2)
Mehmet Oz, MD, Cardiology, answeredOnychoschizia, or nail splitting, doesn’t usually pose any health threat to the rest of the body. The most common cause of onychoschizia is frequent wetting and drying of the nails. But like many nail symptoms, onychoschizia can be a clue to a larger problem. If onychoschizia occurs in both the toenails and the fingernails, the cause is more likely due to a medical issue, such as a hormonal condition or nutrient deficiency. Certain medications, including those derived from vitamin A, may cause onychoschizia in some people. If all of your nails are brittle and splitting, talk with your doctor.
Honor Society of Nursing (STTI) answered
Onychoschizia typically only affects the fingernails. The fingernail can split both vertically and horizontally and is commonly associated with nail dehydration. However, onychoschizia can also be caused by different illnesses that affect moisture levels in the skin and body like psoriasis and Sjogren syndrome.