There has been a lot of talk about this since the death of John Travolta's son Jett.  There was some rumors that he did not receive the medical help he needed because the family are scientologists.  Lisa Marie Presley has been very vocal in saying that it is not true that Scientology is against medical care.  She said that a scientologist is sick, they go to a doctor and if medication will help, they take it. 

I think they prefer to seek alternative natural methods but they are not against modern medicine.