Pharmacology - Approx. How long after oral administration before the biotransformation to morphine?

[PsychoActivist]

So yeh, SWIM was just curious, from what he has read, a biotransformation occurs in the liver in which a certain % of Codeine is converted into Morphine ( I guess cause it's more lipid soluable?)
SWIM was curious if anyone knew how long after oral administration it took place. Is it a continious process that happens over the course of a few hours or does it begin as soon as the liver begins to metabolize it.

In short SWIM had some Pod Tea earlier (the question is only really codeine related that's why he posted here) and he plans on taking 1mg of Alprazolam shortly. He knows GFJ and Cimetidine work to potentiate Benzo's in the same way they do Opiates so he wanted to take a Cimetidine before the Alprazolam but he does not want to interfere with the biotransformation and he is afraid of the Cimetidine occupying the enzymes in the liver where the biotransformation occurs.

[TheNewLeft]

take it and don't worry.

Reputation Comments on this post:

Sorry but this answers the said question in no way shape or form and gives no explanation to anything. No logic. Just 5 ...

[RoboCodeine7610]

Well, this is what I found on a popular online encyclopedia:

Cimetidine is a known inhibitor of many isozymes of the cytochrome P450 enzyme system[7] (specifically CYP1A2, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4).

The conversion of codeine to morphine is catalysed by the isozyme CYP2D6 which is inhibited by cimetidine.So it probably wouldn't be dangerous but it will completely inhibit any effect from the codeine.

[nibble]

Honestly I wouldn't even think about it, morphine in fact probably plays only a very minor role in the analgesic/euphoric properties of codeine as < 5% is metabolised to morphine and this morphine is further rapidly metabolised. The major metabolite codeine-6-glucuronide is apparently the primary chemical responsible for codeine's effects..

[downersdreams]

Morphine is eliminated 90% through the first pass of the liver when used orally. IV is around 90-100% bioavailability.