@mathewsw, I would like to welcome you back to Mayo Connect. I hope that you are doing well.

I had itching before my transplant, and so I know that members will appreciate reading your post. I had never heard of the drug Tremfya, so I did a quick search and learned that Guselkumab (Tremfya) is an injection is used to treat moderate to severe plaque psoriasis in patients who may benefit from receiving phototherapy (ultraviolet light treatment) or other treatments. Plaque psoriasis is a skin disease with red patches and white scales that do not go away.
Guselkumab injection is also used alone or with other medicines (eg, methotrexate) to treat active psoriatic arthritis,...

Do you have a liver condition along with plaque psoriasis, psoriatic arthritis or other skin condition? Are you using Tremfya and has it brought you relief?