What is pre-systemic metabolism?
Understand the Problem
The question is asking for an explanation of the concept of pre-systemic metabolism, which likely refers to metabolic processes that occur before a substance enters systemic circulation in the body. This could relate to pharmacology or biochemistry, where understanding this concept is essential for comprehending drug metabolism and efficacy.
Answer
Presystemic metabolism is how drugs metabolize before entering systemic circulation, reducing bioavailability.
Presystemic metabolism, also known as first-pass metabolism or first-pass effect, refers to the metabolism that occurs when a drug is administered orally and enters the liver, where it undergoes extensive biotransformation. This reduces the drug's bioavailability, meaning less of it reaches systemic circulation.
Answer for screen readers
Presystemic metabolism, also known as first-pass metabolism or first-pass effect, refers to the metabolism that occurs when a drug is administered orally and enters the liver, where it undergoes extensive biotransformation. This reduces the drug's bioavailability, meaning less of it reaches systemic circulation.
More Information
Presystemic metabolism greatly affects the effectiveness of orally administered drugs by limiting the amount of active drug that reaches the bloodstream. This must be considered when dosing medications.
Tips
A common mistake is confusing presystemic metabolism with the normal metabolic processes that occur after drugs are in systemic circulation. Understanding this concept is crucial for pharmacology.
Sources
- First pass effect - Wikipedia - en.wikipedia.org
- Pre-systemic metabolism of orally administered drugs - pubmed.ncbi.nlm.nih.gov
AI-generated content may contain errors. Please verify critical information
