I've always believed that my psychiatrist knows more about and the treatment of mental illnesses. While GPs and psychiatrists are both MDs, the psychiatrist has additional training in the treatment in mental illnesses. When I was first diagnosed I did my med management with my GP. We went through many meds and dosages, but nothing was helping.
I actually lost it one day at work and ended up on a leave of absence. I started seeing a psychiatrist and was put on the right cocktail. When I went back to my GP for my annual checkup and I told her what happened she was more concerned that she may have done something wrong. I would hope our GPs want what's best for us.

In Scotland, is your psychiatrist able to take you off work and provide your treatment without your GPs input?

Good Luck