There are some reports of side effects of varying degree, but in general Harvoni's side effects are extremely mild. When I did the trial, my physician indicate

There are some reports of side effects of varying degree, but in general Harvoni's side effects are extremely mild. When I did the trial, my physician indicated that in previous trials, patients couldn't reliably distinguish Harvoni from a placebo. My experience aligns with this statement. While I was on a 24 week trial (longer than most people today) with ribavirin (which is only used with a minority of patients today), I experienced nothing I could directly attribute to the medication. My viral load dropped to undetectable in six weeks, and has remained so since.