Posted by bluedog on February 8, 2003, at 12:58:00
In reply to Re: Half-life, posted by viridis on February 8, 2003, at 0:04:19
Here's an interesting question for you regarding the half life of diazepam. I have been driving myself crazy trying to do the maths on this one but I have been assuming a completely linear decrease in the amount of diazepam that will show up in my blood plasma levels at certain intervals. In the Benzo equivalence charts it shows that diazepam (and it's metabolite) have a a half life of 30-200 hours. Now for the sake of simplicity I have actually assumed that the half life for a healthy average male of say around about 30 years of age would probably be closer to 24 hours.
I take the following doses of diazepam on a daily basis:
8.00am - 5mg
2.00pm - 5mg
10.00pm - 5mg.I set my alarm for 7.00am each morning and am interested to know what my blood plasma level of diazepam will be each day when my alarm sounds. My VERY crude calculations (assuming a half life of only 24 hours and a completely linear decrease in the blood plasma level of the drug) have yielded the following results.
DAY ONE - Prior to to commencing taking the drug when my alarm sounds at 7.00am my level of diazepam will of course be nil.
DAY TWO - at 7.00am my blood level will be approximately 10.63mg
DAY THREE - at 7.00am my blood level will be approximately 16.89 mg
I am confused and believe that at this rate of consumption the my blood plasma level of diazepam (or it's metabolite) will continue to accumulate and will actually increase on a daily basis. My questions are as follows:-
1) Are my calculations and assumptions correct?
2) Is it not the case that with each successive day the level of diazepam in my blood will continue to increase leading to a higher and higher level of the drug in my system with the consequence that I will find it increasingly difficult to get out of bed each morning when my alarm sounds at 7.00am?
3) Would the levels continue to increase so that I would eventually become none functional and could the levels in theory continue to increase until I would end up with a fatal accumulation of the drug in my system? Of course if the half life is in fact closer to the 30-200 hours shown in the benzo equivalence charts then the accumulation in my system may be even more pronounced
4) Can you please explain this to me and clarify whether my assumptions are correct or whether in fact the blood plasma levels of diazepam in my system would actually at some point stabilise and if so at what level (in mg) would this stabilisation occur?
My gut feeling says that my assumptions must be wrong but I simply don't know why. I hope my questions will not drive you around the twist like they have done to me. Then again you may enjoy my questions and be able to explain it all to me :):).
Thanks in advance guys
warm regards
bluedog
poster:bluedog
thread:139500
URL: http://www.dr-bob.org/babble/20030208/msgs/140155.html