Search results
Results from the WOW.Com Content Network
First-pass metabolism may occur in the liver (for propranolol, lidocaine, clomethiazole, and nitroglycerin) or in the gut (for benzylpenicillin and insulin). [4] The four primary systems that affect the first pass effect of a drug are the enzymes of the gastrointestinal lumen, [5] gastrointestinal wall enzymes, [6] [7] [8] bacterial enzymes [5] and hepatic enzymes.
Transdermal estradiol bypasses the intestines and liver and hence the first-pass metabolism that is associated with oral administration. [ 10 ] [ 96 ] In addition, unlike oral estradiol, transdermal estradiol is not associated with supraphysiological concentrations of estrone or estrogen conjugates like estradiol sulfate, and transdermal ...
In particular, the oral route is subject to a high first-pass effect, which results in high levels of testosterone in the liver and consequent hepatic androgenic effects, as well as low potency due to first-pass metabolism in the intestines and liver into metabolites like dihydrotestosterone and androgen conjugates. [2]
Drug metabolism is the metabolic breakdown of drugs by living organisms, usually through specialized enzymatic systems. More generally, xenobiotic metabolism (from the Greek xenos "stranger" and biotic "related to living beings") is the set of metabolic pathways that modify the chemical structure of xenobiotics, which are compounds foreign to an organism's normal biochemistry, such as any drug ...
[2] [3] However, when a medication is administered via routes other than intravenous, its bioavailability is lower due to intestinal epithelium absorption and first-pass metabolism. Thereby, mathematically, bioavailability equals the ratio of comparing the area under the plasma drug concentration curve versus time (AUC) for the extravascular ...
For premium support please call: 800-290-4726 more ways to reach us
Conversely, if it is absorbed by the upper portion of the rectum, progesterone is subject to hepatic first-pass metabolism due to entry into the hepatic portal system via the superior rectal vein. [18] As such, although rectal administration is a parenteral route, it may still be subject to some first-pass metabolism similarly to oral ...
Pages for logged out editors learn more. Contributions; Talk; First-pass metabolism