Are 5 years of immunotherapy and other medications finally sending my body into itching and spotty overdrive?

Eight months ago when I first posted on this site, I was itch and spot free…enjoying life to the full following all that went on after chemo, radio and surgery for  oesophageal cancer ( 2017/18) and  immunotherapy ( herceptin) for metastatic lung cancer (2020-date).. Over the last six months I am wondering if the effects of treatments, which include a whole hoste of other medications for heart and RA issues, are causing the above. I think that maybe ( older) my body is reacting to all this medication and treatments, in the form of spots and itching. Perhaps someone who has had a similar experience could let me know, if this is now going to be a continuing fact of life, or is there something that can be done to stop it. Heat ( sitting or lying in bed) is definitely a trigger and  medicated moisturising creams make it worse. I use a wet flannel to ease the itching. I sleep ok, but often wake up with lots of scratches which I must have done whilst sleeping.

I am 76 years old, like to keep active, and would be grateful for any advice available. I think my GP just put it down to ‘age’.

John