Potentiating Fentanyl with grapefruit juice

[t00cr4zy]

Tried posting in general opoid area, but no responses

SWIM has taken quite a bit of fentanyl; always transmucosaly, but only when SWIM can't get OC's. And his tolerance to OC is getting too high even though he only does opiates every couple months now(and has been doing it this infrequently for over a year now) it takes him 160mg snorted just to get a good nod going.

Anyways....SWIM wants to get a good rush/nod going so this time is he is going to smoke the gel on some foil. But would also like to experiment with potentiating it oraly.

So we all know grapefruit juice inhibits CYP3A4. Which is the main enzyme that breaksdown fentanyl in the intestine. Just wondering if anyone knows somebody who has tried potentiating fentanyl with it.

[jerbles]

I think grapefruit juice works only with oral opiates, and since fentanyl is administered via patch or blotter (sublingual) I don't think it will work at all.

[t00cr4zy]

I know GFJ only works to inhibit CYP3A4 in the intestine, and not the liver. I am talking about if you eat the gel(I said oraly). Eating the gel is the way of ingestine which results in 30% bioavailbility.

I don't doubt GFJ would potentiate eating the gel, really just wondering how much it would increase levels.

[Paracelsus]

You are correct that small amounts (~200 ml) of grapefruit juice only inhibit intestinal CYP3A4 and therefore just first-pass metabolism (therefore only effective with oral use).

But it was shown that large amounts of grapefruit juice also inhibit hepatic (liver) CYP3A4 and therefore should also somewhat potentiate and prolong parenterally administered substrates of CYP3A4.

Few published data are available on this, so I would be careful and start at no more than 30% of the usual dose.

[Psych0naut]

Oral bioavailability for Fentanyl is pretty low. It would be a waste to take it orally, sublingual administration has a much higher bioavailabity. In case SWIY doesn't know what sublingual administration is, it's placing a substance under ones tongue, and letting it absorb through the vein under the tongue. Swirling it around ones cheeks(bucal administration) works very well too. Ow, could SWIY post a experience report in the Fentanyl experience thread? Only a few Fentanyl experiences have been posted yet. Thanks!

[t00cr4zy]

SWIM understands oral bioavailbility is low, and SWIM has a good amount of experience with fent sublingualy although his preffered ROA is INasal.

SWIM just wanted to try expirementing(he gets large amounts of fent pretty cheap, and doesn't have a habit to support ie; no WD) potentiating it oraly. So he doesn't care if he "wastes" a little in the name of 'science'.

From what SWIM knows about potentiating, using GFJ(and possibly benadryl/tagament also) might go a long way to increase the oral bioavailibility of fent. Correct him if he is misunderstanding how fent is metabolized and and absorbed when taken oraly and if GFJ and other potentiators won't be as effective as he thinks.

I'll see if he is up to writing a report when he tries his potentiation expirement.

[Paracelsus]

The reason why many drugs have a low bioavailability usually is that they undergo first-pass metabolism in the gut. Grapefruit juice inhibits intestinal CYP3A (which is one of the enzymes that metabolize fentanyl), therefore increasing bioavailability. Might be worth experimenting with.

[jerbles]

hmmm... swij cuts his H with diphenhydramine (benadryl, dormin) as it potentiates the nod greatly for him.

I wonder if the fentanyl gel could be mixed with benadryl and set out to dry, then snorted. Anyone think this would work?