1. Don't worry about Codeine inhibiting it's own metabolism to Morphine. It never stopped people from getting high on Codeine.
The only problem is for redosing Codeine, but if you wait a few hours, that should be fine (especially if you take 2. in account)
2. More and more studies seem to show that the metabolism of Codeine into Morphine only plays a LITTLE role in the effects of Codeine.
I could be other metabolites, that are not affected by CYP2D6 that give the effects of Codeine.
3. Alcohol can not really be used as an enzyme inhibitor or inducer, because it INHIBITS the P450 enzymes (CYP2D6, CYP3A4, etc...) during acute consumption and INDUCES these enzymes when administered chronically.
But when you're a chronic alcohol drinker, ALL P450 enzymes are induced, so:
-more CYP2D6 (that makes more Codeine converted to Morphine; but gain, the conversion to Morphine may play only a very little role in the effects of Codeine, compared to other metabolites, such as Codeine-6-Glucuronide)
-more CYP3A4 (this is the enzyme that breaks the Morphine down, so the little more Morphine that you may have created is gonna be eliminated much faster and be weaker...)
And how do you draw the line between ACUTE and CHRONIC alcohol consumption anyway? It can be tricky in some cases...
4. Other examples show that you can forget about INDUCING CYP2D6.
ALL CYP2D6 inducers listed on websites dedicated to that:
-rifampin
-glucocorticoids (dexamethasone, ...)
-carbamazepine
-phenobarbital
are also CYP3A4 inducers: they make the Morphine converted weaker and make it eliminated much faster...
(personnal experience: during an Opoiate withdrawal, I had bought a shitload of Codeine and an OTC Glucocorticoid/enzyme inducer, Beclomethasone. When I would take both of them, the Codeine would kick in much stronger, but then the high would wear off as soon as I would feel it.... Not worth...)
5. Glutethimide is a drug that's almost impossible to come by and that is said to induce CYP2D6.
I don't know if that is true or not, but there are many accounts of Glutethumide being taken with Codeine and the combination enhancing the Codeine high to the extreme.
Is it due to enzyme induction? I cannot find reliable infos on that sorry...
----------------------------
The best way to enhance a Codeine high with the CYP2D6 theory is to avoid any CYP2D6 inhibitor.
But from what I read or see around me, it seems that almost everyone taking Codeine is taking a CYP2D6 inhibitor at the same time.
CYP2D6 inhibitors:
-ALL antidepressants
-ALL antihistamines (so often advocated as Codeine potentiators)
-DXM (same)
-most antipsychotics
-Cimetidine (Tagamet)
-many many other medications/drugs...
There are 2 drugs that DON'T mess with CYP2D6 enzymes and have been said to potentiate Codeine:
-Loperamide
-Grapefruit Juice
Maybe the best is to stick to these....
----------------------------
---long time no posts... I'll come back for long one day, maybe in a few months---
