Drug A increases heart rate by eight beats per minute on the average. Drug B increases heart rate by 16 beats per minute on the average. Suppose both drugs were administered simultaneously. Which of the following changes in heart rate is not an illustration of an interaction?
A) +24
B) +16
C) +8
D) -8.

Question

Quizplus · Accepted Answer

An interaction implies that the effect of combining two drugs is different from the sum of their individual effects. Since Drug A increases heart rate by 8 beats per minute and Drug B by 16 beats per minute, their combined effect without interaction would be a +24 beats per minute increase in heart rate (8+16=24). This choice represents the sum of their individual effects, not an interaction.

Drug a Increases Heart Rate by Eight Beats Per Minute