Why are pharmacology studies so experimental?

Question

I am a med student, and as far as I see from our pharmacology lectures, pharmacologists work almost completely experimental. Quite typically they take a substance (e.g., from nature), they add, change or remove some chemical groups, and then they test it (either with high throughput screening or on animals), for example to see whether the new drug is active or not. To me, this sounds a bit indirect. Ideally, we should know exactly what we are targeting, and then custom-make a new drug. For example, if we know which receptor (the 'lock') we wish to activate or inhibit, why do pharmacologists not simply design a fitting key (a plug to block, or a substrate-resembling activator) to the specific lock?

Answer 1

Hello,

the modern approach to drug discovery is actually more like what you describe in the second half of your question. Put simply, we generally have a hypothesis as to how a specific target (receptor, enzyme, etc) might play a role in a disease process and then seek molecule lead compounds that bind in a selective manner to the particular receptor or enzyme.

What you describe, taking a substance or extract from nature, is something hat was done before the birth of modern pharmacology.