Bioequivalence and Bioavailability Forum • it seems possible for me...

it seems possible for me... [PK / PD]

posted by yjlee168 – Kaohsiung, Taiwan, 2016-09-24 22:19 (3102 d 13:03 ago) – Posting: # 16670
Views: 18,456

Dear mittyri and Elmaestro,

If we re-arrange the equation of Vss = (dose_po x F x AUMC_0-infinity) / AUC²_0-infinity as Vss/F = (dose_po x AUMC_0-infinity) / AUC²_0-infinity. For extravascular dosing, we only can calculate Vc/F, Vss/F, or Cl/F.

❝ ... we need to know MIT,..., t_lag and k_a

No need to know MIT (or t_lag and k_a). Again we can also re-arrange Vss = (F x Dose/AUC_0-infinity)x MRT as Vss/F = (Dose/AUC_0-infinity)x MRT = Cl x MRT.

We can get the values of all parameters (Dose, AUC_0-infinity, AUMC_0-infinity and MRT) on the right-hand sided both equations after NCA. So I wonder why we can not calculate Vss.

—
All the best,
-- Yung-jin Lee
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Complete thread:

volume of distribution at steady state martin 2011-10-18 07:49 [PK / PD]
- Vss d_labes 2011-10-18 11:36
  - History Helmut 2011-10-18 16:02
    - History javier 2016-09-21 16:47
      - Amazon? Yes. yjlee168 2016-09-22 11:30
        
        Gold Letters d_labes 2016-09-22 12:09
        
        Gold Letters yjlee168 2016-09-24 20:26
        
        Another quest mittyri 2016-09-25 15:04
        
        TopFit: 16bit DOS-application Helmut 2016-09-25 23:41
        
        TopFit: less than 1.44 MB mittyri 2016-09-26 00:02
        
        TopFit: less than 1.44 MB Helmut 2016-09-26 00:17
        
        TopFit: less than 1.44 MB ElMaestro 2016-09-26 09:43
        
        TopFit: 16bit DOS-application yjlee168 2016-09-26 00:18
- volume of distribution at steady state ElMaestro 2016-09-23 23:13
  - Vss: MIT is needed anyway... mittyri 2016-09-24 00:38
    - it seems possible for me...yjlee168 2016-09-24 20:19
      - Leslie disagrees mittyri 2016-09-24 21:33
        
        OK! we cannot calculate Vdss with dataset from extravascular dosing alone yjlee168 2016-09-25 23:27
        
        MRTINF includes Mean Input Time mittyri 2016-09-25 23:45
        “Gravity Duration” Helmut 2016-09-25 23:47
    - Was Leslie wrong about Eq (8)? yjlee168 2016-09-26 00:13
      - Leslie cannot be wrong mittyri 2016-09-26 00:23