Eli5: what is the difference between a generic drug to the original drug, and why do some doctors will swear by the original drug?

Question

Eli5: what is the difference between a generic drug to the original drug, and why do some doctors will swear by the original drug?

In: 1046

Answer 1

I work in the pharma industry (though i dont have a phd so take this with a grain of salt). One thing I’ll add to the great answers is that there is a big difference between replicating small molecules and large molecules (biologics). For small molecules, it’s very easy to create exact replicas- so most doctors really should be fine with you taking the generic. For biologics, it’s very hard to prove the new “copy” is exactly the same. Therefore, with this added uncertainty, many physicians are more comfortable prescribing the long-studied drug rather than the newer biosimilar product.