You can fight against the
metallic taste by having citrus juices, lemonade
and foods marinated in vinegar. They not only break through the taste, but also help in saliva production that helps in washing away the metallic taste. Every time you brush your teeth, make sure to brush your tongue also. It will help in lessening the metallic taste. You can use some oral mouthwashes also. This should help.
But if the symptoms persist then please consult a doctor for a complete examination.