Question

Following a single empirical dose (500mg Q12H) given by oral admin, Stacey had a Cmax of 50mg/L and tmax of 2 Hours while Georgina had a cmax of 200mg/L and a tmax of 2.5 hours. Comprehensively explain why the tmax and cmax values are different between stacey and georgina.

*2 pages single spaced needed so as many ideas as you can think of please :)*

Answer 1

C_max is the maximum (or peak) serum concentration that a drug achieves in a specified compartment or test area of the body after the drug has been administered and before the administration of a second dose.It is a standardmeasurement in pharmacokinetics t_max is the time at which the C_max is observedafter oral administration, C_maxand t_max are dependent on the extent, and the rate of drug absorption and the disposition profile of the drug.

(Pharmacokinetics and bioavailability)

when a drug is introduced into the body by extravascular route such as oral, intramuscular, subcutaneous, or transdermal administration, an absorption phase that transfers the drug from the absorption site into the systemic vascular system must take place. plasma-level time curve for a drug administered by oral route; unlike the IV bolus, there is an absorption phase and the overall rate of change in the amount of the drug in the body .

Some physiological factors such as gastric-emptying rate and motility of the intestinemay cause delay in the oral absorption after single oral administration of some drugs in some candidates.  The process of drug protein binding has very little effect on the elimination t_½of the drug excreted mostly by active secretion, while for drugs that are excreted only by glomerular filtration, the elimination half-life may be changed markedly according to the binding affinity of these drug for plasma proteins.( renal problem)

Disease process in liver affect the cmax and tmax

Disease in the GI tract may affect the both tmax and cmax

Chemical property of drug will decide ax and cmax