First order kinetics is constant fraction of the drug getting metabolized. So with the values given in the question stem, 16/32=.5 aka 50% of the drug gets metabolized every 6 hours. Then if you write out the decreasing doses (multiplying each value by .5) for until you get close to 1.1, it'll look like the following:
32->16->8->4->2->1
So it took 5 half lives to get to 1 (closest to 1.1). So since each half life is occurring at every 6 hours, you then multiple 5x6=30.
submitted by โokokok1(38)
First order kinetics is constant fraction of the drug getting metabolized. So with the values given in the question stem, 16/32=.5 aka 50% of the drug gets metabolized every 6 hours. Then if you write out the decreasing doses (multiplying each value by .5) for until you get close to 1.1, it'll look like the following:
32->16->8->4->2->1
So it took 5 half lives to get to 1 (closest to 1.1). So since each half life is occurring at every 6 hours, you then multiple 5x6=30.