First of all, a generic drug only obtains its marketing authorization after having provided a pharmaceutical file and data from bioequivalence.
Bioequivalence studies ensure that the generic drug releases the same amount of active ingredient into the body at the same rate as the original drug, thereby ensuring that the generic drug has the same therapeutic effects. Original drug.
Regarding original drugs, I remind you that the drug market is free. The laboratory that discovered the molecule has the right to continue to market its medicine, even when the patent falls into the public domain.
Finally, to answer your question on the use of generic drugs by healthcare professionals, a survey carried out by the BVA institute in February 2016 revealed that 82% of general practitioners and 97% of pharmacists questioned declared that they were treated with drugs. Generics when sick; 93% of doctors and 99% of pharmacists say they are satisfied.