Omeprazole

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Omeprazole

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antidepressant
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03/31/08 - 10:27 PM

I knew omeprazole is a hepatic P450 inhibitor, in one explanation of kaplan q bank, it said omeprazole has no effect on P450. is it right?

thanks.

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macintosh
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04/03/08 - 01:13 AM

you said it yourself it inhibits the cyctochrome p450

Tiff
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04/03/08 - 08:44 AM

I thought omeprazole induces p450. not inhibiting it.

antidepressant
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04/03/08 - 01:27 PM

Hey Tiff, what is your source, in kaplan pharmacology page 230, it says, omeprazole inhibit P450. the question was from qbank kaplan. where i got opposite. rolling eyes

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Tiff
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04/04/08 - 10:27 PM

I just looked it up in my pharm text - Lange Basic & Clinical Pharmacology. In Chapter 4 there is a list of P450 inducers and omeprazole is definitely on the list. It induces CYP1A2.

I also checked some sources on the web which confirms this.

http://books.google.com/books?id=etk4BoRUFp8C&...

http://books.google.com/books?id=HzvvMGI5kLcC&...

http://www.sciencedirect.com/science?_ob=ArticleU...

new_n_lost
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04/05/08 - 06:13 PM

Got a Problem here Katzung says it inhibits P450 Enzyme family. ?? will confirm from better sources.

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new_n_lost
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04/05/08 - 06:18 PM

Ok figured it out

Katzung Says that it induces CYP IA2 which leads to increased metabolism of the acetoaminophen,sclozapine, TCAs, Haloperidol, theophylline, warfarin

While it INHIBTS CYP- 2C19 which leads to decreased metabolism of Phenytoin

Hmm will chk it from better sources.

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new_n_lost
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04/05/08 - 06:34 PM

http://medicine.iupui.edu/flockhart/table.htm << The most updated page.

http://www.aafp.org/afp/980101ap/cupp.html

Both of the articles clearly say the same essential thing in Katzung. Hunting for more better references.

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macintosh
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04/05/08 - 08:42 PM

Now I am confused.

antidepressant
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04/07/08 - 12:53 PM

#10

lol,macintosh, thanks nnl, that was a great help! i hope they dont test this one! sticking out tongue

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Tiff
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04/07/08 - 02:23 PM

#11

new_n_lost wrote:
http://medicine.iupui.edu/flockhart/table.htm << The most updated page.

http://www.aafp.org/afp/980101ap/cupp.html

Both of the articles clearly say the same essential thing in Katzung. Hunting for more better references.

Thanks for clarifying. That helps alot. I guess it's importatnt to know how it can both induce p450 and inhibit it. Probably more important to know major drug reactions such as with Phenytoin as you mentioned.

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