Sometimes, the health care providers especially in er, give complete different or opposite medical advises? For example, my sister has diagnosed tachycardia for which she takes beta blocker. The condition was diagnosed by the electrophysiologist. Then t

I . I agree with you, this definitely happens. It can depend on the doctor's training, their practice, what they themselves have seen and diagnosed in the past, and the way they understand the question. It can also depend on their "frame of reference", or how they are viewing the situation based on their fund of knowledge. The same thing most likely happens in other professions, such as investment advisors giving conflicting information, or even mechanics. It is frustrating for patients and their families, but it is good to keep asking the questions and obtaining different opinions.