About 25 years ago I was given an anti-viral med for Chronic Epstein Barr Disease that caused permanent neurological damage and gave me a learning disability. I also used an asthma inhaler that made my asthma progressively worse until a friend told me it had been black box listed and my doctor took me off of it. I can't tell you the names of those drugs or the manufacturers might try to sue me.
When using prescription medications it's important to re-read the lists of precautions in the packages every so often, because side effects may not show up until someone has been using the drug for months or even years.
Some people can experience side effects that are not even listed. For example I know a couple of people who have had joint replacements and have increased pain in those areas if they use antihistamines, but there probably were no people with joint replacements in the groups of people used for testing those medicines.
Natural or herbal remedies can also cause problems. One herbal remedy brought on seizures in a child I knew, and I developed allergies to a couple of them myself.
I'm not saying we shouldn't take medications, but it's important to weigh the benefits against the disadvantages and pay careful attention to any changes that may occur.