I have posted before about my dog and her skin condition.  Before lockdown my dog was prescribed some capsules from the animal hospital consultant.   Worked wonders.  My dog is no longer under the animal hospital. The original prescription was given to my vet to get the capsules.  I asked them for some more plus another spray but the vet has said no unless consultant says it is alright.  Bonkers. I know my dog, discharged from hospital, finished.  The last thing I was told from the hospital was to get an anti-fungal shampoo.  Waited 3 months for the vet to get some.  They ordered the wrong thing, charged me £27 before I realised that and then I found out it was over the counter at £4 a bottle. Phew! got that off my chest.

When the original prescription said 30 capsules they only got 15 to start off with as they were expensive. Got the other £15 eventually. Bonkers again.

I have been under a referral dermatologist with mine for years now. We are unlikely to be discharged as it is ongoing allergies and neither would I want them to suggest it
I am surprised if yours in an ongoing problem they discharged him 
.in our case the dermatologist vet contacts my vet if I am getting g meds through them or I go direct to the dermatologist. My vet cannot   write prescriptions as my dog is not under them for this condition  unless directed by the derm vet
In your position I would do one of 2 things either go back to the original refereal vet and explain the situation  and that to enable u to continue  getting the right meds you  need them to prescribe.
Or see your vet and ask  them to treat your dog so they can then prescribe.  .Without him being under them for the condition they can't prescribe
Hope that makes some sense

Thank you for replying.  I discharged my dog not the consultant.  We can no longer go to the hospital as the journey is too far and I cannot travel well.  My husband and I are shielding.  I spoke to consultant yesterday and have agreed that we will see him in 4 weeks.  He told me to buy Nizoral human shampoo from the chemist before her bath at the groomers.  Also I am supposed to be getting the capsules or prescription from him but not heard anything yet.
Thank you for understanding and help.

Totally understand why u had to discharge your dog . Difficult situation in even more difficult conditions.i hope u are both well and that u are able to get what is needed for your dog with out more stress

Btw u can the shampoo recommended nizarol on line from Amazon if that helps.