Effective therapeutic concentration

DYPHYLLINE Dyphylline is a derivative of theophylline it is not a theophylline salt, and is not metabolized to theophylline in vivo. Although dyphylline is 70% theophylline by molecular weight ratio, the amount of dyphylline equivalent to a given amount of theophylline is not known. Specific dyphylline serum levels may be used to monitor therapy serum theophylline levels will not measure dyphylline. The minimal effective therapeutic concentration is 12 mcg/mL. 

The optimally effective therapeutic concentration of phenobarbital is between 15 and 40p.g/mL. The predominant side effect observed in adults at blood concentrations greater than 40[Xg/mL is sedation, although tolerance to this effect develops with chronic therapy. 

The minimum effective therapeutic concentration of valproic acid is 5O 0,g/mL. Concentrations in excess of 100 tg/mL have been associated with hepatic toxicity and acute toxic encephalopathy. Glycine has been observed to accumulate in patients on valproic acid therapy. 

The drug is found to be effective against amaebic hepatitis in man as well as hamsters. Unfortunately, the drug fails to show any specifically promising activity against the intestinal infections, most probably by virtue of the fact that it gets rapidly absorbed and do not reach the lower intesine zone in an effective therapeutic concentrations. 

Dendrimers are small (typically less than lOnm in diameter) in comparison to other drug-delivery vehicles such as linear polymers, micelles (50-200 nm), and liposomes (100-1000nm). The small size results in rapid renal filtration and elimination via the urine compared to larger carriers. To reach an effective therapeutic concentration of the drug in the tumor tissue, a dendritic drug carrier needs to balance kidney clearance and elimination via the fiver and reticuloendothelial system (RES) against the passive accumulation resulting from the EPR effect. RES clearance is more pronoimced for... 

The BCF mentioned above has its benign counterpart in the effective therapeutic concentration (ETC), which has been encountered in Practice Problem 2.1. Both result when the rate of inflow of the material is exactly balanced by the rate of elimination. Thus, although the two substances are at opposite poles, one, toxic, the other, therapeutic, the mechanism by which they reach their plateau values are identical. 

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