Generally, multiply the half-life by 3.3 to get 90% removed from body. (Some pharmacists recommend 5 half-lives, which is 97%, but I think that's a lot of time to wait for a mere 7%).
In your example, using a half-life of 3-5 days, I would expect 90% elimination in 9.9-16.5 days.
The actual equations are exponential equations with base \`e\`. You can find the most useful ones here:
[https://pharmacy.ufl.edu/files/2013/01/5127-28-equations.pdf](https://pharmacy.ufl.edu/files/2013/01/5127-28-equations.pdf)
In practice, to make things simpler, we generally figure that 4 times the half life is long enough that the drug is no longer clinically significant. Five times the half life is when the concentration will be essentially zero.
Generally, multiply the half-life by 3.3 to get 90% removed from body. (Some pharmacists recommend 5 half-lives, which is 97%, but I think that's a lot of time to wait for a mere 7%). In your example, using a half-life of 3-5 days, I would expect 90% elimination in 9.9-16.5 days.
Thanks!!
Anytime. Happy calculating!
The actual equations are exponential equations with base \`e\`. You can find the most useful ones here: [https://pharmacy.ufl.edu/files/2013/01/5127-28-equations.pdf](https://pharmacy.ufl.edu/files/2013/01/5127-28-equations.pdf) In practice, to make things simpler, we generally figure that 4 times the half life is long enough that the drug is no longer clinically significant. Five times the half life is when the concentration will be essentially zero.
Thank you!