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Diphenoxylate - a non-analgesic opiate

fastandbulbous

Bluelight Crew
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Does anybody have any information or ideas as to why diphenoxylate has all of the characteristics of other opiates (abuse potential, substitutes for others in preventing withdrawl, reduces gastric motility, depresses breathing etc) but shows no properties as an analgesic. I was under the impression that if a drug was a mu receptor agonist, then it would also have analgesic properties.

Any insights would be appreciated
 
Is it a mu agonist for sure?

I was thinking more in terms of it being a very strong delta or sigma agonist but not much for mu.

I am probably wrong though.. just taking a stab at it ;).
 
Martindales Extra Pharmacopia, among others, states that diphenoxylate has no analgesic activity. It does everything either pethedine or methadone does (it's structure is a hybrid of those two chemical families), except kill pain. It's hydrochloride salt is nigh on insoluble as well (not related, just another weird thing about it as well)
 
It probably doesn't enter the brain, similar to loperamide.
 
But it causes euphoria and will maintain a morphine dependance

See what I mean about strange?
 
I have taken high dosages of lomotil before and experienced definite opiate/analgesic effects. This is the first claim I know of that contends it is not an active narcotic.
 
i recently ttried 16 or so lomotil and used cwe ate the left over residue and didnt feel shit... maybe if i used more but as of now i wouldnt go out of my way for the stuff
 
Well in terms of equivalent potency in preventing onset of withdrawl, 50mg of diphenoxylate is equivalent to 100mg of pethedine, so it's not that potent - 16 lomotil contain 40mg of diphenoxylate.

MGS
I'm not saying it doesn't feel like an opiate (I've had lomotil with the atropine removed before and got a definite effect), just that it doesn't give any pain relief; every other aspect of opiate intoxications shows except for analgesia
 
It does enter the brain, just poorly... I just don't believe this statement that it is not anagesic... Maybe they mean "you shouldn't use it as an analgesic".
 
I think one of the refs given in Martindales is for a tail flick nocioception testing, and that it was almost as good as useless (my summary, not their words!)
 
I used diphenoxylate a few years ago and it definitely had opiate effects. It was quite nice. Not as strong as hydrocodone though. I do not remember the dosage but I took 5 or 6 of them.
 
Dipheoxylate hcl DOES cross the blood-brain barrier and DOES cause analgesia/"opiation" but not real opiate euphoria. Its a perfectly legitimate opiate, it just has a different character to it, which happens to not lend itself well to abuse. But obv it can work well to fight withdrawals/as a maintenance drug.

Its a VERY close cousin of demerol, which is obviously quite recreational, it just so happens that the slight chemical difference makes its...meh.
 
Oh well, this thread is oooold, but nonetheless I'd to provide some help with answering FnB's original question:

Diphenoxylate has 4.9 times more (tail clip assay) resp. 5.9 more (hot plate assay) analgesic activity than morphine sulfate, according to the resp. ED50-values. The ref is J Exp Pharmacol Ther 1977, 203(3), p.512.

The EC50-vaules for the tail clip assay / hot plate assay [mg/kg i.g.]:
Morphine-SO4: 43 / 56
l-Methadone: 13.8 / 15.0
Diphenoxylate: 8.8 / 9.5

I remember to have read somewhere that the analgesic properties of diphenoxylate come into effect only shortly before the toxic ones. That said, it's probably like Bilz0r said in post #10:
I just don't believe this statement that it is not anagesic... Maybe they mean "you shouldn't use it as an analgesic".

- Murphy
 
I used to quite like Diphenoxylate. I recall even when I shouldn't have been able to feel it, I would. I liken it to a long acting demerol with less of the demerol side effects. (less of the irritation and hallucinogenic effects of demerol).
Also very little sedation. But a definate euphoria. I used to note that it constricted my pupils to a great degree. In retrospect, something very bupe about it. More mu effects than bupe, but I think it's duration, especially in high doses, may be what triggers the comparison.

It takes awhile for the euphoria to build. I believe it's the main and active metabolite causing the euphoria. (don't recall the name, maybe difenoxic acid, or difenoxin or some similar.)

Sort of how ORLAMM had to build up to di-nor-lamm to really feel good.

I suspect it's analgesia was downplayed to keep it on the down-low, in C-V, and off the radar, so they could go ahead an market it as the Main go to drug to stop you up, before loperamide. If
it's analgesic effects were played up, and it was understood to be a full, strong mu-agonsit like the rest of em', then it wouldn't be such an easy to dispense drug. Time was, I could get it OTC easier than The codeine preparations. Time was, it was quite common to sign out.

Like I said I liked it, and don't agree with the 50mg= 100mg of pethidine.
From what I recall, 50mg, which I did take, and which I would be able to feel the atropine starting to have effect, would produce a very long lasting mu-agonist experience. 100mg of demerol wouldn't do much of anything at that point but even 15mg of lomotil would have me pinned.

My guesses as to the analgesia are just conjecture, but my memories of it's
experience are quite clear to me.. I had a fondness for this overlooked opiate.
I recall reading that it had a history of IV abuse, possibly abroad, and this is what lead
to the US formulation to add atropine.
 
I'm curious as to what a "recreational" dose of this would be. I was prescribed these awhile back for a GI Virus and IBS. I have about 19 2.5mg of these left.
 
I think I've heard of liquid formulations of diphenoxylate being injected but that is probably a very bad idea. but that is why the solubility doesn't matter people weren't mixing powdered diphenoxylate they were using the liquid formulations like liquid lomotil to start with.
 
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