Biology Pharmacokinetics: Volume of Distribution and Total Body Clearance

AI Thread Summary
The discussion focuses on understanding the pharmacokinetic concepts of total volume of distribution (V_c) and total body clearance (Cl_total). V_c is defined as the volume into which a substance distributes, calculated as the dose given divided by the initial concentration. The connection between V_c and Cl_total is explained through the formula Cl_total = k_e V_c, where k_e is the elimination rate, indicating that clearance measures the volume of plasma cleared of a substance per unit time. Participants emphasize the importance of accessing various resources, including textbooks and online articles like Wikipedia, for deeper understanding. Overall, the conversation highlights the complexity of these pharmacokinetic concepts and the need for multiple sources to grasp them fully.
Master1022
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Homework Statement
What is the meaning behind the total volume of distribution and total body clearance concepts?
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Hi,

I was recently reading through Systems Kinetic Modeling notes and am struggling to understand the concepts of total volume of distribution and total body clearance.

As far as I understand, the total volume of distribution ## V_c ## is the "volume of the compartment into which the substance has distributed itself" and can be written as:
V_c = \frac{\text{Dose given}}{\text{Initial concentration}} = \frac{D}{C_p (0)}
is this correct?

Then, I don't understand the intuition between the connection between ## V_c ## and the total body clearance ## Cl_{total} ##, which can be written as ## Cl_{total} = k_e V_c ## where ## k_e ## is the elimination rate. We weren't told about it during the lectures and I just found the formulae above on the internet.

Is this because the total body clearance is supposed to measure the volume of substance within the plasma that is cleared per unit time?

Any help would be greatly appreciated.
 
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Maybe somebody will spell it out for you, but don't count on it. It is hard work for anyone to actually replace, write from scratch, textbooks. If one book or source is not adequate look for another. There seems to me quite a good and thorough article on Wikipedia https://en.wikipedia.org/wiki/Clearance_(pharmacology)

I hope you realize the connection between this and your previous question of about a week ago that I hope to come back on, unfortunately I am pretty short of time.
 
epenguin said:
Maybe somebody will spell it out for you, but don't count on it. It is hard work for anyone to actually replace, write from scratch, textbooks. If one book or source is not adequate look for another. There seems to me quite a good and thorough article on Wikipedia https://en.wikipedia.org/wiki/Clearance_(pharmacology)

I hope you realize the connection between this and your previous question of about a week ago that I hope to come back on, unfortunately I am pretty short of time.
Thanks @epenguin, will take a look at that! I agree that using materials online is helpful, but am unfortunately unable to access such textbooks at this time. However, I am sure this topic is taught widely enough that there will be plenty of other resources for me online (wikipedia page looks pretty helpful from a first glance)
 
Widely taught, yes and no. It seems part of a much more general course you are doing. By no means every student everywhere will have a textbook including this and rarely more than one, though they may have more availability in libraries. If you amplify a little the account of yourself and studies on your personal page, maybe say where you are, any special circumstances, helpers here will likely take it into account. I will try add a little to other thread later today or tomorrow.
 
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