What happens when you mix two opiates that metobolise differently

[Altered Perception]

I am very sensitive to drugs however if i dont overdo it I can tolerate them hence the following question...

I take oxycodone liquid daily for chronic pain, I used to take tramadol but I found that I have an exteremly slow onset reponse to tramadol as it takes me 4-5 hours for the tramadol to work after ingesting it possibly due to it being a pro drug that gets converted by the liver.

So my question is...The Oxycodone liquid takes 30 minutes to kick in, the tramadols takes around 5hours, if I took them together at the exact same time is it a safe bet to say that the tramadol would not at all interact with the oxycodone ? or would it likely to interact due to the chemicals being mixed up during digestion? so I guess what I want to know is even though tramadol takes 5 hours to kick in would it have any immideate noticable interaction on the metobolisation of oxycodone?

 

[Altered Perception]

let me rephrase this in another way: I made the mistake of taking tramadol bout 5 minutes ago and my my pain has got worse since so i cant wait 5 hours for the tramadol to take effect so im considering taking oxycodone now, however because both drugs have a considerable effect on me due to my a chemical sensitivity, and depsite the difference in onset time Im still concerened whether they may have any influence on one another on a pharmacological level when taken at the same time?

 

[amapola]

I'm not familiar enough with their exact metabolic pathways to fully comment. It is safe to say though that there would be interaction as both of these are substrates of similar enzymes (mainly CYP3A4 and CYP2D6) and will both be passing through the liver from the moment they begin to be absorbed from the GI tract which if taken at the same time will be almost simultaneously.

edit:
For your personal situation Altered Perception if you must take some oxycodone, all I can recommend is that you titrate up extremely slowly which I know is hard if it takes 30min to kick in

The tramadol though could very well limit the effect of CYP3A4 on the first pass metabolism of the oxycodone and though it won't be inhibited like grapefruit juice and just compete with it there are no guarentees one way or the other how much of an effect it will have. Sorry.

 

[Altered Perception]

Yes thats exactly what I was asking, even though I wont feel the tramadol working for another 5 hours I am still aware that the process of conversion begins in the liver long before as soon its absorbed from the GI tract , so essentially what I wanted to know was what happens if you drop another substance in there like oxycodone during the conversion process in the liver.

I've ended up in hopsital twice now when I took oxycodone 6 hours later after having taken tramadol but I was already feeling the effects of the tramadol at the time when I took the oxy however in this case I have another good 5 hours so somehow i thought maybe there is a chance I can take the oxycodone which is rapid onset and will keep me painfree for 3 hours and by the time it wears off the tramadol would begin to kick in and it would be just ideally perfect, but as you pointed out its not that simple, thanks for your help

 

[amapola]

Yeah you won't have to worry about the effects of the tramadol combining with the effects of the oxycodone. Just if the tramadol which is currently being metabolized causes more of the oxycodone to pass through the liver unchanged and result in too high of a dose for you.

 

[Altered Perception]

I see, thanks very much you have clearly answered my question.

So I guess if the interaction is that of a inhibitory or inducing type then I suppose a formula would potentially exist where one could take more or less of the oxycodone and get the same effects as have taken their regular dose?

Im not willing to experiment but its just good to know, although im tempted to just take 1/3 of my usual dose and see if the tramadol balances out the rest, but i'l play it safe for now.

 

[amapola]

So I guess if the interaction is that of a inhibitory or inducing type then I suppose a formula would potentially exist where one could take more or less of the oxycodone and get the same effects as have taken their regular dose?

Yes. However I'll clarify that tramadol does not from what I know notably inhibit nor induce any enzymes. It is merely a substrate which will (if you will) use up some of the enzymes. In small doses there are likely enough of the enzymes left over to properly process the oxycodone as well but of course even a small increase in dosage can have unwanted effects for someone in your situation.