[Spirochete]

How does the chloroquine differ from the hydroxychloroquine now being discussed? Or is it just semantics?

It was developed in the 1930s by Bayer scientists working for the Nazis, so it pre-dates hydroxychloriquine by two decades.

[Ozark Tom]

It’s the difference between the effectiveness of DFDT and DDT—less side effects and a lower effective dose.