I say this every time this comes up but do y'all listen? Hell you don't.
Never go to a doctor in Central.
It's that simple. Just go a few yards down the road to a normal place like Sheung Wan or Wan Chai (or anywhere that's not Central) and see a normal doctor.
If you go to a doctor in Harley Street with a slight cough, don't be surprised if you end up with a large bill and stay in hospital for throat surgery. Give the poor doc a break, the profit on prescriptions for cough medicine are not going to pay for a fancy office in Harley Street and a bigger fleet of Rolls Royces than the doctor next door are they?