Thanks to drugs many problems have been eliminated: tetanus, polio, hep b, measles, mumps, rubella, the list goes on. (shout out to India which has been polio free for 3 years!)
Drugs has also helped a lot to keep people healthy, keep their brains active and even function better (kaptive, caffeine, etc), help ease pain, and make various operations and treatments possible.
I don't really have any specific examples from my area, I guess since it's exam period I should point out the number of people using glucose and caffeine (among other things) to maintain and increase brain performance.