1 DRUG IN BLOOD EXISTS IN EQUILIBRIUM WITH __ 2 In equilibrium, the concentration of the drug in blood different (greater or lesser) than the concentration of the drug in tissues. This is due to the __ 3 The greater the concentration, the __ is the amount of drug transfer. 4 the rate of transfer of a drug from one compartment to another is __ to concentration of the drug in the compartment from which it exits;