Kel or λz? [PK / PD]

posted by Helmut Homepage – Vienna, Austria, 2014-12-28 14:56 (3847 d 15:16 ago) – Posting: # 14182
Views: 12,723

Hi Astea,

❝ Can you please give me some links where to find the information of how to calculate Kel for drugs with enterohepatic recycling?


If you are dealing with an oral dose it is practically impossible to claim enterohepatic recycling. A second peak may also be the result of transfer for the stomach to the duodenum, a food effect (increased hepatic blood flow), etc. Only if you see a second peak after an iv dose you have strong hints. Many models exist, and without an IV dose and sampling faeces PK parameters are not identifiable. No idea about the web. [image] it. Standard PK textbooks contain examples.

❝ What part of the curve we should use for analysis? :confused:


The latest one. If you are talking about BA/BE we are only applying NCA (i.e., we are not dealing with PK models: \(\small{\lambda_\textrm{z}\neq k_\textrm{el}}\)). Only make sure that you have at least three samples in the log/linear decline and AUCt covers ≥80% of AUC.

Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz
[image]

The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes

Complete thread:

UA Flag
Activity
 Admin contact
23,430 posts in 4,931 threads, 1,675 registered users;
63 visitors (0 registered, 63 guests [including 19 identified bots]).
Forum time: 07:13 CEST (Europe/Vienna)

It has yet to be proven
that intelligence has any survival value.    Arthur C. Clarke

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz
HTML5