The drug cocktails used to treat sick fish are a common scenario I see, with owners travelling from shop to shop to be recommended one treatment after another.
Some drugs do more harm than good,
some may be directly toxic to fish, some may wreak havoc with your biofilter creating toxic water conditions and some when used incorrectly, can lead to bacterial antibiotic resistance.
Even if the medications themselves do no harm, it eats into valuable time and the disease can spread to others and it can progress beyond recovery.
Previous treatments given may also mask signs of disease and may make it more difficult to diagnose the cause of disease. So it is very important to seek veterinary attention immediately at first signs of disease.
