Thank you to all that responded. It seems more patients had a month of Allipurinol tablets alongside hydroxy or ruxolinitib. This is good to hear.
I checked my bloods and serum urea has been at the top of the range or higher than the top range. Uric acid has never been tested.
I am not sure if this substance is the same or similar to uric acid, but are both related to kidney function and seem to be waste products that can cause pain in joints.
I often have inflammatory issues in joints on account of sarcoidosis and also have arthritis, so appreciate anything that does not make this worse.
I will keep you updated as I go along!