antihistamines to potentiate opiates

[Anon54]

Ive tried diphenhydramine, promethazine & doxylamine. I find promethazine to be the best sleeping aid with the least side effects although i havnt had much experience with doxylamine.

anyways im a bit confused about which antihistamines potentiate opiates
on wikipedia it says dph potentiates some opiates.

im assuming it works different with codeine to other opiates.

im mainly concerned with codeine & oxy.

would taking 25mg of promethazine potentiate codeine?
what about oxy?

I also am currently taking zyprexa which which like other antipychotics are also antihistamines but im not sure how strong antihistamines they are compared to the other ones.

Do u think Antipsychotics could potentiate opiates?

the one im confused about is codeine because i remember reading a debate on bl a long time ago saying that antihistamines potentiates opiates except codeine because it has to convert to morphine & it slows the process down. I cant remember exactly what was said & I cant find the old thread.

I think it was said that grape fruit juice works with the opiates except codeine. is this right?

 

[Deleted member 170540]

Last summer I tried opiate potentiation by taking 50mg hydroxyzine(atarax) with 200mg codeine... After an hour I noted only typical mild codeine effects with not much potentiation, so I decided to drink a six-pack of beer to potentiate it even more. After that I nodded so hard that I pissed myself and didn't notice it... lol

 

[nAON]

1st gen antihistamines are gonna potentiate because they have some sedative effects as well. I think promethazine also inhibits metabolism, which is why it may not work with codeine as codeine is mostly a prodrug, not sure about that though.

 

[Escapedysphoria]

You're right Anon, you don't want to use GFJ to potentiate codeine because it's slows the conversion of codeine into morphine, which is crucial for a proper codeine high. Antihistamines potentiate codeine just fine, promethazine is an especially good potentiator for codeine IME. Yes, I believe some antipsychotics which are also antihistamines at certain dosages can potentiate an opiate high. The only antipsychotic I found to be useful for potentiate were low doses of Seroquel (25 mg or below). Since oxy tends to be a more stimulating opioid high, I've found that more sedative antihistamines potentiate oxy best my preference being hydroxyzine. I haven't had the chance to use hydroxyzine lately, but its anxiolytic properties make it an ideal potentiator for opioids.

 

[Anon54]

but for the same reason GFJ doesnt work with codeine, should promethazine work either.
it all confuses me
I used to take seroquel now zyprexa. but fuck seroquel is so sedative. try taking 200mg.
I had like 75mg of valium the other night & didnt even come close to what 1-2 seroquel do.
ive got a friend who gets 150mg seroquels. 1 of them would knock anyone out.
i remember having 150mg when i was stoned once & i had to stagger my way to bed straight away.
i dont mind antipsyhotics. for someone who has imsomnia it can be a good feeling knowing that ya gunna have no trouble going to sleep.

 

[Escapedysphoria]

but for the same reason GFJ doesnt work with codeine, should promethazine work either.
it all confuses me
I used to take seroquel now zyprexa. but fuck seroquel is so sedative. try taking 200mg.
I had like 75mg of valium the other night & didnt even come close to what 1-2 seroquel do.
ive got a friend who gets 150mg seroquels. 1 of them would knock anyone out.
i remember having 150mg when i was stoned once & i had to stagger my way to bed straight away.
i dont mind antipsyhotics. for someone who has imsomnia it can be a good feeling knowing that ya gunna have no trouble going to sleep.

Liquid codeine w/ promethazine feels much more potentiated and euphoric as opposed to just plain codeine IMO. I'd much rather have diazepam than an antihistamine with my opioids though haha, or both

 

[effie]

"Potentiation" is a confusing term. To truly potentiate something a substance has to interfere with it's metabolism a la white GFJ. Often anything that adds to the sedation is said to potentiate opioids (benzos, sedating antihistamines etc) as the two combined have more of an effect than the opioids on their own.

Promethazine, diphenhydramine and other antihistamines do inhibit CYP2D6, which is involved in the metabolism of many opioids and benzos, so they could be said to be true potentiators as well as the added benefit of being sedating so adding to the nod.

CYP-450 chart for anyone who is interested (CYP-450 is a class of enzymes in the liver responsible for metabolising many drugs)

Codeine is a complicated one. It's metabolised by CYP2D6 to morphine, and this is inhibited by GFJ, cimetidine, promethazine, diphenhydramine etc, so you would think that it would be a bad idea to inhibit this. However, only approx 10% is converted to morphine and actually it seems that most of codeine's opioid effects come from a different metabolite, codeine-6-glucuronide, which follows a different metabolic pathway (can't remember which one, 3am here haha) or even from codeine itself. So actually, IMO (and IME) it is worth potentiating codeine the same way you would a different opioid or benzo.

Info on potentiating opioids:
Ultimate opioid potentiation megathread in Other Drugs

 

[Escapedysphoria]

Codeine and morphine do have very distinct differences in the highs IMO.

 

[mrflowers00]

i'm on zyprexa and it dose nothing to boost my opiate highs

 

[VaderisBaddAss]

What is the best time to take hydroxyzine before taking either Dilaudid or Oxy? Can I take them at the same time or do I need to take the hydroxyzine like an hour before?