kaplan LN - samideb12

[ArchivalUser]

A 500 mg dose of a drug has therapeutic efficacy for 6 hour.If the half-life of the drug is 8 hr ,for how long would a 1 gm dose be effective ?
A.8 hr
B,12 hr
C.14 hr
D.16 hr
E.24 hr
Can someone help me understand this question.I always fail to figure it out.Thank you in advance.

[ArchivalUser]

500 mg TE: = 6 hours ...t 1/2 = 8 hours
1 gram = 1,000 mg

so basically you want to know how long 1,000 mg be effective ...
in this the half life is basically a trick part... so u ignore it and concentrate on TE

if 500 has TE of 6 hours then 1,000 would have TE of 12 hours....

so answer :

BBBBB



if im wrong please correct me i'd also like to know but thats how i would work the problem!!!!

[ArchivalUser]

0 hr - 1000mg
8 hr - 500mg

So we have the initial 8 hours that the drug will be working for before the half life is reached, and after that, when there is 500mg left over, it will work for an additional 6 hours.

8hr + 6hr = 14 hr

Answer: CC

[ArchivalUser]

so i tried the question and got it wrong DARN!!!!!

the explanation in kaplan makes sense though!!! ill wait for others to explain and answer!!

[ArchivalUser]

darn ur good mutation.... as ive stated before ur ready!!

[ArchivalUser]

1 gram=1000mg

500 mg has theraputic efficacy....for 6 hours
1000mg............first half life.....8 hours.....>500.......second half life..............8 hours.....250
.............................................8............................................+........6=14....................

[ArchivalUser]

Hello,

Could you please post correct answer and explanation?

Thank you so much,

Elpida

[ArchivalUser]

Hi Elpida

This Q is from Kaplan pharma LN. Please look in the Practice Questions of Section 1 "General Principles." It is Q # 10 and you will find its answer there.

Good luck.