Yes, the point of the drug is to suppress the immune sytem enough so that it will not reject the foreign organ. Your body will kill off any kind of transplant because it is not a natural part of you body. This is why immune-suppressant drugs are essential. A strong immune system is essential for good health. So it really is impossible to be healthy while taking anti-rejection drugs. Trying to improve your immune system while taking these would be a bad idea. Your body could reject the organ and then you would die. It's really bad!!