What is the difference between the pharmacology terms "oral clearance"
and "systemic clearance," referring to the metabolism of drugs in the
human body?  (i.e. "The oral clearance of midazolam was significantly
increased during St. John's wort administration, but the systemic
clearance of midazolam was unchanged.")

Zoegardner-ga,


Systemic clearance refers to the clearance rate of a drug after it's
been administered intravenously.

Oral clearance, in contrast, refers to the rate of clearance of drugs
administered orally.

The two rates can be quite difference, since oral administration
usually does not result in 100% delivery of the drug beyond the
stomach.


I hope this answers your question at the level of detail that you
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All the best,

pafalafa-g


search strategy:  None.  Used my personal knowledge of toxicology to
answer the question.

Just the answer I was looking for, thanks.