Calamine gives relief for a short time only. It is suggested to get the liver function test as itching all over the body can signify a liver issue which is caused due to the Pregnancy hormones. As you are almost full term the doctor may be expecting that you would go into labor anytime soon.

I suffered at the end of my pregnancy....do one thing for instant relief u can also use cold water n sankhjeeru powder

Same I suffered during 5th month I hd to medicine ask ur doc

same happened with me when I was pregnant

yes please do LFT test.. apply lacto calamine twice or thrice. Drink more water and eat egg or eat food which includes high protein