I mean, if it looks serious enough, it's better they have all the possible information. If the doctor told him his diagnosis or reason for the meds or what the meds are that would be bad practice, but from how close they looked they just simply assumed he'd might know a basic fact about him (for their presumed closeness), especially if not taking kr taking would cause serious side effects. (Worked two jobs in the medical field
Also i don't think these are sensitive personal informations , he said that he will talk about it when he wakes up
It could be that Juheon is Dohu's hospital guardian! Usually a family member is the guardian role but it sounds like they reached out but since they can't come fast enough maybe Juheon volunteered. In Korean hospitals you need to have guardian with you when you get admitted and stay with you during your hospital stay bc there's not enough nurses to do everything like in the states. And the guardian is there to know the updates from the doctors and test results etc to help coordinate the hospital stay and take care of the patient. I think they can even sign consents for procedures
it's Korean doctor
They even have fake doctor on plastic surgery patient
So just telling his friend his symptoms it's nothing
Not the doctor just revealing sensitive personal information to a person they have already determined to be "only a friend"...