drug levels in saliva

From: "nelamangala nagaraja" <nvnagaraj@hotmail.com> Subject: drug levels in saliva Date: Wed, 14 Jun 2000 14:22:12 EDT Dear NM users, I am trying to analyze plasma and saliva levels of a drug and its metabolite. I have already analyzed the plasma pharmacokinetics separately (USING ADVAN6). I would like to know how to proceed with analyzing the saliva levels for the two entities. The options are: 1. Separately calculating the predicted saliva levels given the plasma concentration using Henderson-Hassellbalch equation and comparing the observed and predicted saliva levels. 2. Simultaneously fitting plasma and saliva levels in ADVAN6, again using Henderson-Hassellbalch equation and considering a THETA and an ETA for the salivary pH. (NO DIFFERENTIAL EQUATION FOR SALIVA LEVELS). Since salivary pH is known to be variable, I would like to use option #2. I have got some good results by the option #1. I would like to know whether it is OK to simultaneously fit plasma and saliva levels and if so, could you please suggest a way to code it. Thanks Raj N.V. NAGARAJA, POST DOC RES ASSOC DEPARTMENT OF PHARMACEUTICS, UNIVERSITY OF FLORIDA, GAINESVILLE, FL-32610 PH: 352-846-3257