It is true that God can heal the mind, just as He can heal any other part of the body. Sometimes He does, and sometimes He does not heal. Psychiatric medications aren't a perfect solution, but, like many other treatements, they are sometimes part of the only reasonable way to proceed.

You certainly can and should pray to be healed, but never stop taking medications without consulting with your doctor. It is not a lack of faith or spirituality to consult and follow your doctor's advice. The brain is a part of our body, and sometimes requires help to function normally like other parts.

You should also be talking to a Christian counselor, because medication alone is usually not the complete solution, and you need encouragement and direction along the way.