We are open for safe in-person care.
Featured conditions Brain tumor, breast cancer, colon cancer, congenital heart disease, heart arrhythmia. See more conditions.
Featured conditions
Subscribe to Housecall
Our general interest e-newsletter keeps you up to date on a wide variety of health topics.
In the type of patchy hair loss known as alopecia areata, hair loss occurs suddenly and usually starts with one or more circular bald patches that may overlap.
Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.
Check out these best-sellers and special offers on books and newsletters from Mayo Clinic.