Drug at the target site

To make predictions (for example, to predict the dose needed to maintain the concentration of the drug at the target site within a therapeutic window). 

Pharmacokinetic interaction the drugs interact remotely from the target site to alter plasma (and other tissue) concentrations so that the amount of the drug at the target site of clinical effect is altered, e.g. enzyme induction by rifampicin will reduce the plasma concentration of warfarin enzyme inhibition by ciprofloxacin will elevate the concentration of theophylline. 

To assess the effectiveness of a drug delivery system compared to the drug itself, one can dofinQ dL site-exposure enhancement factor (SEF) to measure the change of the AUC of the active drug at the target site after administration of the delivery system compared to administration of the drug alone ... 

Nanoparticles are defined as particles with physical dimensions between 1 nm and 1000 nm (Lovestam et al., 2010]. They have been used to restrict the access of drug at the target sites and to deliver the drug at a controlled rate at the site of action (Sagar et al., 2011]. Khalil et al. formulate warfarin-p-cyclodextrln loaded chitosan nanoparticles for transdermal delivery. Chitosan is a hydrophilic... 

Generally it may be said that one should choose such binding methods which do not lead to a loss of activity of the antibody, and moreover make possible the release of the active drug at the target site. Also, it should be remembered that binding of antibodies to reactive polymers is, in fact, a reaction of multifunctional compounds, so that one should select such reaction conditions which prevent an extreme rise in molecular weight... 

An ideal ophthalmic formulation should be installed in the ocular area without causing any irritation or blurred vision [29]. The in-situ gel-forming drug delivery system is often considered as suitable ophthalmic formulation because after administration in the ocular area, it immediately undergoes phase transition to form viscoelastic gel, which in turn enhances the residence period of the drug at the target site to yield better drug performance [66]. 

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