is 2% considered to be safe or risky?

[kenny1999]

From the medicine or clinical point of view, if a medicine will result in adverse effect for 2% of patients who take it, is the medicine considered to be safe, generally safe, very safe or risky? I know that there may not be an absolute answer to this question but I just want to get some generally accepted thoughts or opinions.

[John Cuthber]

It would be an exceptionally safe drug.

Even placebos have about a 5% risk of adverse effects.
https://www.ox.ac.uk/news/science-blog/harmful-placebos

[OldChemE]

I think you need to put the risk in context to make a good judgement on it.  For example, when I was still teaching I had roughly 200 students I saw regularly in the course of a day.  2% would be 4 students that I knew well.  If we were talking 2% risk of a deadly consequence - absolutely unacceptable.  But, a useful medicine with a 2% risk of children missing a few days of classes -- totally OK.

[Phi for All]

3 minutes ago, John Cuthber said:

It would be an exceptionally safe drug.

Even placebos have about a 5% risk of adverse effects.
https://www.ox.ac.uk/news/science-blog/harmful-placebos

Isn't there a difference between a side effect and an adverse effect, or that not all side effects are adverse? I had a US physician (not necessarily the best source of pharma knowledge) once tell me that adverse effects are always bad, but side effects can sometimes be used beneficially, such as a medication that causes drowsiness as a side effect that works well for an insomniac.

It's bizarre that a placebo could have an extreme adverse effect. I can understand someone making themselves nauseous, or having pains brought on by belief in a placebo, but your article cites deaths due to this effect. I had no idea it was that strong.

I would also suppose the particular adverse effect makes a difference. If 1 in 50 patients who take a drug gets severe abdominal pain, the doctor can take that person off of it immediately. If the adverse reaction is kidney damage, you might not catch that in a timely manner.

[TheVat]

The deadliness of the disease being treated factors in too.  If the drug treated pancreatic cancer, whose five year survival rate is around seven percent, then the patient would likely agree to a drug or procedure with some serious risk of adverse effect.  

[CharonY]

The question cannot be answered properly with the parameters driven. The first obviously is the type of risk. Mild symptoms are viewed differently than severe or potentially fatal ones. Short-term issues are different than potentially chronic issues.

Others have already mentioned the lack of a control (i.e. what is the rate in placebo groups, for example). And in addition there is also the question of what the drug/treatment is against. Even severe symptoms might be considered acceptable, if the untreated outcome is high risk of death, for example. 

Due to the complexity regarding pharmaceutical safety, it is not judged on a simple safe/unsafe dimension. It should be stressed that there is no drug that is safe under all circumstances. I.e. one should not take drugs without indication. A drug is at best "safe" for a given purpose and that is what you can see on the labels, together with the likelihood of adverse effects commonly encountered.

 

Edit: managed to cross-post with others, so much has already been said. 

 

  

50 minutes ago, Phi for All said:

Isn't there a difference between a side effect and an adverse effect, or that not all side effects are adverse?

Well, there has been a discussion on this and in all actuality there are no side effects either. Biologically, of these are effects. The difference is mostly whether they are desired (in a given context) or not. But it has been universally ruled that this level of accuracy is going to confuse consumers.

[swansont]

Fig 1 in this paper has a category for > 1 in 10 (very frequent), so there are some side-effects that happen a lot.

https://www.nature.com/articles/s41467-020-18305-y

But, as CharonY has noted, it depends on the seriousness of the side-effect vs untreated outcome. Nausea from cancer meds is common, AFAIK, but that’s accepted because the affliction is fatal. But a fatal side-effect from a nausea medication would probably not be tolerated.

[Sensei]

"The dose makes the poison"

https://en.wikipedia.org/wiki/The_dose_makes_the_poison

Everything is poison and nothing is poison, depending on the amount of..

 

[CharonY]

2 hours ago, swansont said:

Fig 1 in this paper has a category for > 1 in 10 (very frequent), so there are some side-effects that happen a lot.

https://www.nature.com/articles/s41467-020-18305-y

But, as CharonY has noted, it depends on the seriousness of the side-effect vs untreated outcome. Nausea from cancer meds is common, AFAIK, but that’s accepted because the affliction is fatal. But a fatal side-effect from a nausea medication would probably not be tolerated.

Another thing that I forgot to mention is efficacy, as that obviously has a huge impact on overall evaluation.

[iNow]

I was once in a plane that lost cabin pressure and was barreling at several hundred mph toward a sharp rocky mountain outcrop, but wasn’t sure whether or not it was safe or risky to strap on the parachute before jumping out into a skydive because it was old and only deployed 98% of the time. 

[John Cuthber]

The difference between pharmacology and toxicology is intent.