Do drugs with the same chemical formula work identically?

Question

As a simple example, H2O molecules are identical, but water can have three different forms (liquid, vapour, ice.) What about more complex matters, like drugs? Can they have different forms which work differently?

Answer 1

Do drugs with the same chemical formula work identically? The short answer would be yes, with the best example provided by the FDA and their view of generic equivalents “generic drugs are chemically identical to their branded counterparts” (FDA, 2017). Even though the drug molecules may be identical, the compound manufactured may be different (different excipients, formulations, coatings, manufacturing processes, etc…). The example you provide regarding physical differences of H2O molecule (liquid, vapor, ice,) would be similar to the different formulations of more complex drug molecules ( tablet, liquid, vaporized liquid, etc…). Same drug molecule, just different physical properties.

Hope this helps

Ed W

FDA, (2017). What are generic drugs. Retrieved from https://www.fda.gov/drugs/generic-drugs/what-are-generic-drugs

Answer 2

Yes, there are drugs with the same chemical formula that work differently. These are called isomers. You can find more information here https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3614593/