can confirm JW's take medicine like normal people
My wife's grandfather is an Elder, and he has survived cancer four or five times. He's had radiation so much they refuse to give it to him any longer.
Her grandmother died of cancer a few years back, and she had chemo, radiation, etc.
I will say that they were very much into home remedies that they pulled from the Bible for basic stuff. She always told me to rub olive oil on myself like the guy in My Big Fat Greek Wedding told people to put Windex on stuff.