free AUC

Dear nmusers, If i have only the AUC of a drug. Can I calculate the fAUC using the equation: fAUC=AUC * f ? where f stands for the free fraction of the drug ? Is there another solution ? Regards Kalan

Hi Kalan, The answer is a bit more involved and requires additional information, such as the route of administration (i.e.- IV vs. oral) and information relating to the hepatic extraction ratio for the drug. In short, I'd recommend reviewing a thorough presentation of the derivation in Rowland and Tozer's "Clinical Pharmacokinetics: Concepts and Applications" + a presentation available at: www.uiowa.edu/~c046138/CLh.ppt Regards, Matt ~~~~~~~~~~~~~~~~~~~ Matthew M. Riggs, Ph.D. Metrum Research Group LLC [EMAIL PROTECTED]

Hello You can calculate free AUC, as you have described, only if the relationship between total and free concentration is linear and the free fraction remain constant throughout the dosing interval. Fatemeh >===== Original Message From Khaled Nm <[EMAIL PROTECTED]> ===== >Dear nmusers, > >If i have only the AUC of a drug. Can I calculate the fAUC using the equation: fAUC=AUC * f ? where f stands for the free fraction of the drug ? >Is there another solution ? > >Regards >Kalan Fatemeh Akhlaghi, PharmD, PhD Associate Professor in Pharmacokinetics Biomedical and Pharmaceutical Sciences (BPS) University of Rhode Island 125 Fogarty Hall, 41 Lower College Road Kingston, RI 02881, USA Phone/Fax: (401) 874 9205/(401) 874 2181 Email: [EMAIL PROTECTED] Laboratory Website: http://www.uri.edu/pharmacy/faculty/aps/akhlaghi/index