what causes metal taste in mouth
Dysgeusia can cause a number of different alterations in taste, including a metallic taste. Some common medical conditions that can cause metallic taste in the mouth include ear or upper respiratory infections such as sinusitis, as well as head injury or conditions that damage the central nervous system (CNS). A history of radiation therapy to the head and neck can also cause a metallic taste in the mouth.
Gum disease is a very common condition where the gums become swollen, sore or infected. The gums tend to bleed after you brush or floss your teeth, and the blood in your mouth causes the metallic taste. If left untreated, the tissues and bone that support the teeth can also become affected (known as periodontitis).