what is the coating on the tongue
White coated tongue is a common sign of fungal infection known as Oral Thrush. As it is mostly caused by overgrowth of fungus called Candida, this condition is also referred to as Candidiasis of the mouth and throat.
Every now and then you notice that your tongue (usually a healthy pink) is coated in white. While a white tongue is something that can be alarming, there is no need to worry. Most of the time, the cause of a white tongue is harmless and temporary. The surface of your tongue is covered with papillae. If your tongue is entirely coated in white, you are likely to have an inflammation of the papillae that is caused by dead bacteria, debris and dead cells getting stuck among them.