As you say, in the case of antibiotics, you know about the disadvantages. That knowledge is required in order to weigh advantages against disadvantages. Only after weighing you can decide whether or not to take antibiotics.
That’s also the reason why every medicine is delivered with an obligatory leaflet which describes all possible side effects.
In this case, information was missing. There was no mentioning of the high degree of uncertainty considering the effectiveness of this anema. There was no mentioning of the possible risks and side effects.
All I did was add some information. I do not see how adding information could be harmful.