Induction of Cytochrome P450 enzymes


Excerpt from Cafer's Psychopharmacology, available soon from Amazon


ENZYME INDUCTION

Theopposite of inHibition is inDuction. InDuction occurs when an inDucer
stimulates the liver to produce extra enzymes, leading to enhanced metabolism
and quicker clearance of victim drugs. More often than not, an inducer is itself
a substrate of the enzyme.

The D is for Down, i.e., Decreased serum concentrations of victim substrates.
Unlike inHibition (H for Hurried), inDuction is Delayed, not taking full effect
for 2 to 4 weeks while we...
wait for the liver to ramp up enzyme production.


Induction mnemonics by Jason Cafer MD
InDucers will be depicted by: 
CYP450 enzyme inducer mnemonics by Jason Cafer MD

THE SHREDDERS


The “shredders” are four strong inDucers of several CYPs, which cause countless chemicals to be quickly expelled from the body:
  • carbamazepine (Tegretol) – antiepileptic
  • phenobarbital (Luminal) – barbiturat
  • phenytoin (Dilantin) – antiepilepti
  • rifampin (Rifadin) – antimicrobial
Dr. Jonathan Heldt refers to the shredders as “Carb & Barb” in his book Memorable Psychopharmacology.


St John’s Wort (herbal antidepressant) also inDuces several CYPs, but does so with less potency  than the four shredders.

Can shredding be problematic even if the patient is not taking a victim medication? Consider this:

Induction and Vitamin D mnemonic by Jason Cafer MD
Copyright CaferMed LLC, 2020

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