On the distribution of drugs in saliva and blood plasma.
The equilibration of drug concentrations between blood plasma (unbound part) and saliva was studied for selected drugs with different physicochemical properties: Quinidine, sulfamerazine, paracetamol, diazepam and ethanol. From these and other experimental results it is suggested: 1. The concentration ratio between saliva and blood plasma (unbound) can only equal one for basic drugs with a pK a lower than 5.5 and acid drugs with a pK a higher than 8.5 and for pH indifferent drugs. 2. The drug must have a sufficient permeation ability through lipid membranes, valuable by the lipid water partition coefficient.
On the distribution of drugs in saliva and blood plasma. The equilibration of drug concentrations between blood plasma (unbound part) and saliva was studied for selected drugs with different physicochemical properties: Quinidine, sulfamerazine, paracetamol, diazepam and ethanol. From these and other experimental results it is suggested: 1. The concentration ratio between saliva and blood plasma (unbound) can only equal one for basic drugs with a pK a lower than 5.5 and acid drugs with a pK a higher than 8.5 and for pH indifferent drugs. 2. The drug must have a sufficient permeation ability through lipid membranes, valuable by the lipid water partition coefficient.