Is the doctor's consultation fee subject to legitimate Sharia controls, and should it take into account the general circumstances of Muslims?

The basic principle is not to set a wage for crafts and trades, unless there is a general need for them and their practitioners refuse to provide them except at a price exceeding the customary wage. In such a case, the ruler may compel them to accept the customary wage; this is known as obligatory pricing. This includes the obligation for doctors to set prices for treatment if people are in need of it due to the spread of an epidemic, and doctors refuse to provide it except at a price exceeding the customary wage.