Not far wrong BUT some do work but they do so by providing specific symptomatic relief. The paracetamol will essentially work as an anti-pyretic to reduce your temperature but nothing else in this case. Most others contain things like pseudoephedrine, pholcodine, and caffeine which will help to alleviate symptoms such as blocked noses, coughs and tiredness. In the vast majority of cases they won't help much and the cold will run it's course.
Wow such generalization.
So you not going to take antibiotics or another million medications, that are proved to work.
Also painkillers do work, they kill pain, they aren't made to cure the underlying problem.
Such nonsense.