Time response Relationships

The therapeutic response of most drugs depends on their concentration in the plasma.

the time required for the amount of drug in the body to decrease by 50%

time from point of which drug is administered until reaches a therapeutic range

time from point at which drug is administered until is reaches a therapeutic range

time period from when a drug is administered until its concentration drops out of a therapeutic range

that concentration of drug in the blood serum that produces the desired effect without causing toxicity

-within therpeutic range
-must consider magnitude and frequency of a dose as well as drug half life
-90 percent of drug excreted after 4 half lives and is considered excreted
-repeated dosing required to maintain steady plasma concentration of a drug

larger dose that leads to more rapid absorption and slower onset of action
-maintenance after

Cp x Vd/F

(cp x clearance)/f