Healing services should always include mental illnesses. This gives a clear sign to people in your faith community that all forms of illnesses are valid and worthy of concern.
Faith communities need to be particularly sensitive in this area because there is a history of misguided prayer. Mental illness is not demon possession or God's specifically giving us a "cross to bear" or a sign of God's lack of love for us. It is a disease, like any other disease!
The healing prayers should reflect the biological nature of the illness just like any other disease. We should pray for a healing and continue with sound medical practices.