I itched terribly for nearly 2 years. My hepatologist also prescribed Zoloft as it has an anti-itch side effect. It worked marginally for me, but also made me emotionally flat.
I tried every lotion & gel but always felt sticky. Sarna lotion helped, but I recommend the unscented version. I found that witch hazel helped, but it dries the skin. I would wake up at night multiple times and put witch hazel on a washcloth and just apply it to my skin for immediate relief. The other thing that helped were ice packs. I would sleep with large ice packs in my bed. I think the cold sensation trumped the terrible itching. I would put a towel between my skin and the ice packs.
I also recommend that you purchase simple white cotton gloves that you can wear to bed. These are available on Amazon and are inexpensive. I would scratch to the point of breaking my skin during my sleep, so the gloves helped.

One of the first things I noticed when I woke up post-transplant was that my itching was gone! Blessed Relief!