I always said...that saying to someone that side effects are rare, when it's not the case in reality, will provoke a panic state if the person got one or several, just because he reads that they are rare. "So what is happening to me?!?"
If he knows the truth, that they are common, the person will not panic, because he/she will know that what is happening is normal. "Ah, I got this, I got that, but it's not a surprise. I read that it happens often. I just need to hang on".
Now compare the difference between the 2 ways. Panic, or peace. Reality, or statement based on self happened event only.