"At least a "fake drug" with a placebo effect is safe. "
A "fake drug" is NOT safe, rather it is not effective. The danger is that taking your fake drug will often prevent someone from taking real medicine or seeing an actual physician, thus their condition is not resolved, and can even get worse. People can and have died from that kind of thinking.
Then it's also conning sick people out of their money, which you apparently don't care about either.
Yes, medicines have side effects, and there are some pretty scary looking warnings because of the way they have to list all kinds of things that happen during the study even if it was probably unrelated to the drug. Also, there are billions of variations in humans, so there are unexpected and undocumented differences that won't and can't get tested for. For example, my family has a whole list of drug variations for our doctors. Most pain killers are rather weak, and stimulants tend to put us to sleep.
As to complaints, well, you're going to get those. I've talked to someone that blamed her flat tire on the gas she just got when she filled the tank because it was only about 10 minutes later. In her mind, the one preceded the other, so it must be the cause. On top of that, some people will just complain no matter what. I've done plenty of work over the phone, and in the same day with a rather even and polite tone used all day, I've had people accuse me of being too somber, too cheerful, too friendly, and too businesslike. Often just after the opening spiel, so it's not like there's a chance to do anything other than the canned greeting.
Look up anything, and read the complaints. They will be there, even if you were selling the actual magical age reducing waters of the fountain of youth.
*Please note: I'm not saying that any particular complaint is invalid, or that the body of them isn't indicative, just that the existence of complaints is meaningless. It's better if you can judge the volume of product or services used, and then figure out the quantity of valid complaints to figure out a relative prevalence. I said valid complaints because some people will be very vocal, others will just parrot second or third hand anecdotes, and then there's the nutjobs that have no idea what they're talking about, like the lady that blamed the flat tire on getting gas.
By the way, smart move to talk to your doctor, and it's too bad that you apparently had a negative response to a medication. You did the right thing with that. (Now if I could just get certain stubborn friends of the family to act as sensibly as you did in your incident.)