Burning mouth syndrome (BMS) is a common, but complex problem that causes patients to experience a burning or scalding pain on the lips and tongue (and sometimes throughout the mouth). There are often no visible signs of irritation, and the cause of the syndrome may be caused by various factors, ranging from the onset of menopause to psychological dysfunctions to vitamin deficiencies. BMS may affect up to 5 percent of Americans and usually occurs in people over age 60.