Private prescription and NHS

marcio

I’ve got a shared care agreement between my psychiatrist and GP.
previously to a private psychiatrist I was off work , became homeless and so on. I met my partner, today my husband who paid for me to go privately 12 years ago. I have been work full time since then.
my psychiatrist now wants to change to another medication as I am not feeling well at the moment. The psychiatrist said he can’t prescribe it. NHS guidelines say they can under the advise of a Psychiatrist. This new medication cost £128 per month.

I explained to my GP that I can’t afford both, private psychiatrist and pay medication private. Asked for an NHS referral and which he made it plus 3 months sick note till I get to be seen.

I might have to start the treatment from scratch and he says he can extend my sick note.
I don’t want to go off sick. I’d rather have the right medication and continue to work full time which is also going to contribute to my mental health:

Is there anything I can do to challenge it?

Thanks