White coat syndrome, or white coat hypertension, is the term used to describe patients that get a high blood pressure reading in a healthcare setting and a normal reading at home. The anxiety of being around doctors in white coats can make the patient's blood pressure rise.

It is diagnosed when the patient has at least three in-office readings that are higher than normal but requires either 24-hour ambulatory blood pressure monitoring or home blood pressure monitoring. 

These readings in the office would be 140/90 millimeters of mercury or higher, but the patient's 24-hour ambulatory blood pressure measurement (at home) is less than 135/85 millimeters of mercury.