LIVER TRANSPLANT

sir thankYOU so much for your reply.
let me make the picture a bit more clear to u and ask for your opinion then.my father is a post liver transplant patient. almost an year has pasSed .Now along with all he has got renal impairment problem. His cretanine is almost 1.4 or around. My question is that  should he continue his TACROLIMUS tablets or should switch to some other tablets which are safe for kidneys?
Secondly , in my sorounding there is an opinion that lowering the TACROLIMUS dose also let the liver enzymes to increase? Do you favour such opinions as my father has lowered his tacrolimus dose  to keep his kidneys safe?
Sir ,will wait for your kind reply.
Thanks.

[ALISHER]

HIS MEDICINE DOSE IS:
TACROLIMIS 1mg BD (TWICE A DAY)
CELLCEPT 500mg BD (TWICE A DAY)