Question from NBME test

[Prop]

Hi,

Could anyone please help me with this question, as I cannot figure it out.

"4 drugs produce the same therapeutic effect by the same mechanism, but each has a unique toxicity. When used at a maximally effective dose, the drug with which of the following sets of characteristics is most likely to have the highest incidence of toxicity?"

Median effective dose Toxic dose1/Effective dose99
A) 0.5x 2.8
B) 1x 2.1
C) 5x 4.0
D) 33x 3.0

I know the right anwer is B, but why? I simply cannot remember how to calculate this, so please, could anyone tell me how to (ie. the equation or whatever).

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[fakin' the funk]

Therapeutic index is what determines likelihood of toxicity, not the absolute dose that you have to use. This question relies on you falsely assuming that the absolute dose matters. Pick the drug with the lowest TI.

 

[fakin' the funk]

P.S. it's unwise to post copyrighted NBME info on this forum

 

[JayneCobb]

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