I was just reading an article in PLOS Medicine on the treatment of multidrug resistant TB. They suggest that treatments are more effective if a large number (more than 5) treatments are used simultaneously.
I know also that many infectious diseases are currently treated with combination therapies (eg ACT for malaria, atripla for HIV) to slow the evolution of drug resistance. I was curious if there was a down side to using every (or almost every) available treatment for a given infectious disease, instead of one or a few?
Certainly some treatments come with side effects which are unpleasant enough to avoid them from the start, and there may be instances where different drugs interact to be less effective (or in combination tolerated only in lower, less effective doses). But in general, is there a downside to hitting infectious agents with every potentially effective treatment as a matter of course?