Combining opiates

[OpioidDopioid]

I'm curious exactly how the effects add up when mixing opiates.

For this case-scenario say I'm taking 30mg hydrocodone and 20mg oxycodone. The conversion charts here tell me that these are equivalent doses. So, what I'm wondering is this: Do the opiate effects continue to build despite the drug being different, or do they each act on their own and the effects just combine?

I'll try to be as clear as possible:

Does taking different opiates add up just like taking a single opiate would, or do they each give you their individual effects but combined?

If I take 30mg hydrocodone, and then take 20mg oxy codone, am I going to get a stronger opiate effect than I would with the hydrocodone alone, or do they just sort of cancel each other out?

 

[Cane2theLeft]

Picture it like this: you have empty opioids receptors. Each dose you take that is an agonist for the same receptor adds a bit more to that receptor. 30mg of hydrocodone will add X to that. Taking the equivalent in oxy (20mg - presumably orally) will add the same amount doubling the agonism or effects.

There are exceptions such as with the strong partial agonist buprenorphine. At very low doses, it will have an additive effect with other opioids. The higher you go, the more of a bully it becomes knocking the other opioids off the receptors preventing them from working. Once you take enough bupreonorphine (equal the agonism of 30mg of methadone) essentially no standard doses of other opioids will be able to bind to them because the bupe has blocked the receptors and you would need massive doses to override it's ability to bind to the receptors.