I have a natural nail client who has red moons. They used to be healthy and white, but now they are an angry red about halfway up from the cuticles. She hasn’t changed medications or detergent and she isn’t experiencing any discomfort. What could this be?
Red lunula (moons) are seen in a number of disorders but also can be idiopathic (meaning they occur with no associated disease). Cardiac failure, rheumatoid arthritis, lupus, pulmonary disease, and carbon monoxide poisoning are a few of the conditions that may be associated with red lunula. Also, some conditions that affect the nail can have red lunula such as psoriasis or alopecia areata, but usually there are other visible nail changes with those conditions. Your client should have a good physical examination, but if everything checks out normal, she should not worry about this change. — Phoebe Rich, M.D., is an associate clinical professor of dermatology at Oregon Health & Science University and a member and former president of the Council for Nail Disorders.