Posted by Larry Hoover on February 7, 2003, at 10:56:59
In reply to Back to half-life......... » sl, posted by ShelliR on February 5, 2003, at 13:07:25
> <To follow up on what the previous poster said, if the halflife is 7 hours, you should be safe to try something else within 24-48 hours.>
>
> sl,
>
> how did you calculate the 24-48 hour period in relation to a half-life of 7 hours?
>
> tia,
>
> ShelliThe relationship between half-life (t1/2)and concentration is n(t1/2) = (1/2)^n * initial concentration. So, for a period of four half-lives, the remaining concentration is (1/2)^4, or 1/16. In this example, the half-life is seven hours, so at 28 hours, the concentration is 1/16 of the peak concentration. What should be noted, however, is that the half-life timing period begins not at the time of ingestion, but at the time of peak plasma concentration, which might be as much as hours after ingestion.
At six half lives, the concentration would be 1/64, probably a negligible amount. As Geodon does not have active metabolites, and assuming two hours to reach maximal plasma concentration, at 44 hours ( 6 * 7 + 2)post ingestion there would be 1/64 of the peak level remaining in the blood.
Lar
poster:Larry Hoover
thread:139500
URL: http://www.dr-bob.org/babble/20030204/msgs/139965.html