What drugs does grapefruit juice potentiate?

[Anon54]

I just took some valium & temazepam. I drank about 350mL of white GFJ 45 mins before dosing. I also had my usual milk thistle pill today which is suppose to also potentiate benzos.
http://www.bluelight.ru/vb/threads/608295-Potentiate-benzos-with-milk-thistle
Im still waiting for the benzos to kick in anyways. I found this website on wikipedia stating which drugs interact with grapefruit juice.
Im partially interested in whether it helps potentiate codeine & also temazepam.
http://en.wikipedia.org/wiki/Grapefruit_drug_interactions#Affected_drugs

The benzodiazepines triazolam (Halcion), orally administered midazolam (Versed), orally administered diazepam (Valium), alprazolam (Xanax) and quazepam[3]

I noticed it didnt include temazepam although ive seen other websites say it does.
http://www.bluelight.ru/vb/threads/606434-what-benzos-does-grapfruit-juice-potentiate/page2

Benzodiazepines, especially diazepam and temazepam, may have increased blood levels and augmented effects when taken with grapefruit juice, especially in the elderly.

although kokaino wrote this in the thread "what benzos does GFJ potentiate:
http://www.bluelight.ru/vb/threads/606434-what-benzos-does-grapfruit-juice-potentiate

GFJ potentiates almost all benzodiazepines. The only ones that aren't potentiated by GFJ are the 3-hydroxy family of benzos. These benzo's are temazepam, lorazepam, lormetazepam, oxazepam, and a couple of other more rare benzodiazepines that belong to the same family.

http://www.marinmedicalsociety.org/magazine/articles/?articleid=434

Codeine and Tramadol.[10] It reduces the amount of codeine converted by CYP3A4 into norcodeine thus increasing the amount metabolized into morphine.[citation needed] Morphine itself, however, is not affected by grapefruit juice, as it is not metabolized by the cytochrome P450 system.

In a mouse study, blood concentrations of acetaminophen/paracetamol (Tylenol) were found to be increased by white and pink grapefruit juice, with the white juice acting faster

So there is some conflicting info whether codeine is potentiated but as the last quote says be careful if ya trying to potentiate after popping pills with apap. maybe only with cwe.
This is the interesting one because some ppl think it actually reduces the effect of codeine.

The interaction caused by grapefruit compounds lasts for up to 24 hours and its effect is the greatest when the juice is ingested with the drug or up to 4 hours before the drug.

It says it's Ok to take at the same time as the dosing but some ppl say wait till 30mins-1 hour before hand.
I seen a study saying that 250mL of white GFJ is sufficient to make valium 1.5 stronger & last longer but i dont know if the juice I got is 100% GFJ.
So from the standard white GFJ u get from the shop. how much do u think u need?
does anyone know how long after drinking the GFJ is best to dose?
any experiences with any drugs?
especially with codeine & temazepam?

http://en.wikipedia.org/wiki/Grapefruit_drug_interactions#Affected_drugs
I'll mention this site again because it seems to include all the drugs interactions with GFJ

geez this thread took me a while to make valium & temzepam are kicking in a bit. I dont know why I bother. even though I havnt had it in 2 weeks the tolerance never seems to go away

 

[Anon54]

I see I have no responses.
doesnt anyone know if GFJ can potentiate codeine or temazepam?

OK so like I said I had 60mg diaz & 80mg temaz after drinking GFJ 45 mins before hand. As usual I basically feel nothing from the benzos so I dont know if the GFJ worked but it has been atleast proven with diaz

anyways I just had my usual 400mg dose of codeine & it feels stronger than it has for months. Ive never drank GFJ before taking codeine. Could it be placebo?

any ideas anyone? Wikipedia says GFJ potentiates codeine. usually i feel nothing from codeine cuz of tolerance but im feeling pretty mellow & it was after i had the codeine. i had the benzos hrs ago its not because of them.
Ive mixed benzos with codeine many times so its not because of that combo either. Im actually starting to beleive it's from the GFJ
heres some more info on GFJ from erowid:
http://www.erowid.org/ask/ask.php?ID=2726

One psychoactive drug that grapefruit juice is known to affect is valium (diazepam). In a paper by Ozdemir in the European Journal of Drug Metabolism and Pharmacokinetics in 1998, they found that 250ml of grapefruit increased the peak concentration by 50% and increased the time to peak from 1.5 hours to 2 hours.

Added Aug 2008: While grapefruit juice is known to inhibit enzymes involved in the metabolism of codeine and other opiates, I've been unable to find a clear answer about whether codeine's effects are increased or decreased when combined with grapefruit juice.

it also says that GFJ may potentiate LSD, Psilocybin, and Ecstasy

 

[allegator]

Grapefruit juice inhibits CYP3A4. Here is a list of substrates.
http://www.bluelight.ru/vb/threads/191439-Awesome-CYP-450-Chart!

The effects of codeine (a prodrug) are caused primarily by conversion to c-6-g (and c-3-g) via phase II metabolic pathways and somewhat by phase I CYP2D6 conversion to morphine (which then quickly undergoes glucuronidation itself). Grapefruit juice would likely not affect this at all (and might actually make it worse) however it may affect the absorption of codeine from the gut for better or worse, I don't know.

For temazepam, from wikipedia it is already very well absorbed, and ends up with 90% of metabolites due to conjugation and 10% demethylation so once again P450 will at most be minimally involved. If grapefruit juice is only acting on inhibiting CYP3A4 it won't be of much assistance here either.

 

[Anon54]

^^which inhibitor is GFJ?
oh, I found it. I didnt realize there was more than 1 page lol
it says that GFJ potentiates temazepam.
also, codeine isnt potentiated by codeine.
but it says that diphenhydromine potentiates codeine. what about the other anthistamines?

 

[Pjkt2501]

but it says that diphenhydramine potentiates codeine. what about the other anthistamines?

Gen1 antihistamines are known for being excellent potentiators of opioids.

 

[effie]

Other first gen antihistamines also potentiate in the same way, by inhibiting CYP-450 enzymes (can't remember which right now, or if all do?) but regardless they all also add to the sedation, help with itching/nausea etc.. so are a good choice to take with opioids

 

[allegator]

^^which inhibitor is GFJ?
oh, I found it. I didnt realize there was more than 1 page lol
it says that GFJ potentiates temazepam.
also, codeine isnt potentiated by codeine.
but it says that diphenhydromine potentiates codeine. what about the other anthistamines?

The chart I linked to doesn't talk about potentiation at all, merely how different substances effect the function of your P450 enzymes. You have to understand what they are being broken down into and how much they really on the enzymes first.

For example it says that GFJ inhibits CYP3A4 and that temazepam is a substrate of CYP3A4. However from wikipedia only 10% of temazepam is processed this way and the rest is by phase II conjugation so it won't have that much of an effect. Furthermore it says that codeine is a substrate of CYP2D6 and you were ruing that codeine isn't also a inhibitor of CYP2D6. As I mentioned before though codeine is a prodrug (basically inactive on its own) so you want to induce CYP2D6 which converts codeine to morphine.

 

[Anon54]

i only take oxy sometimes. i know it works for that.
but what about codeine?
its a little complicated as its conversion to morphine & its other metabolites that work

 

[allegator]

For codeine you want to induce CYP2D6 to assist conversion to morphine. Grapefruit juice doesn't effect that nor the phase II metabolization of C-6/3-G. Whether GFJ's acidity helps for absorption of codeine from the gut or not I don't know.

 

[Survival0200]

Also methadone, right? Alfentanil? (And yes: alprazolam, midazolam, triazolam)

 

[benzofan]

Diazepam fore sure

 

[webbykevin]

I don't understand what the purpose of doing this is, why not just take a larger dose of Valium instead of trying to potentiate it ?

I guess if you were trying to make your Valium go a bit further that would be a reason but it's not exactly expensive so I would just up the dose.

 

[THE_REAL_OBLIVION]

Necro alert. I just want to say that if one can take less actual pills for a better effect and save on their so controlled RX (doctors script benzos easily, but 3/4 of pharmacists really hate people with prescriptions) and never try and renew a day or two before the (28 days instead of 30, sometimes someone is shopping that one day because they don't live in town but close enough to it, but it costs 25-30 minutes of gas to get to their damn pharmacy), because most of the time you'll be told you're supposed to have still 4 tablets left or whatever, and often I still do have some, 75% of the time) If somebody who is unfortunate enough to have a valid reason for using benzos everyday, that's a one less source of stress for you.

I've looked through the whole site from a search engine doing "Site:bluelight.org triazolam grapefruit" and there's conflicting posts everywhere.

The benzos I know for sure are not potentiated by grapefruit itself or GFJ is clonazepam, nitemazepam (and all nitrobenzodiazepines you can think of, they don't go through the same enzyme pathways as other benzos) oxazepam (that molecule really has no redeeming qualities) temazepam and lorazepam. Diazepam and particularly alprazolam is....(I had 2mg of xanax this morning, before that I drank 2 full glasses of white grapefruit juice and I still feel the Xanax, we lack Xanax XR in Canada but I don't see a need for it). :D

As for opiates, never bothered, benadryl, promethazine or hydroxyzine was a must, particularly obligatory with oxycodone which gives me one hell of a histamine reaction, often delayed if I take oxycontins, if I do it with a couple or three OxyIR 20's, it doesn't, although I always like a little of one of those three, or pheniramine if feel like chugging a Neo-Citran. Hydroxyzine in particular makes a meh drug like Demerol kick in hard, same with Talwin. But GFJ? Nope, I tried a lot when I had script for CodeineContins 150 and then 200 + 2 or 3 Percodans prn. Then when I snorted Dilaudid, it worked so well with me, I kept it at that for a whole 6 months until I just slammed it and then it was not useful again. If it does turn hydrocodone more into hydromorphone, it's actually a bad thing, to actually feel Hydromorphone orally, when I had a low tolerance to opiates, I had to eat a 24mg Hydromorph Contin minimum (there's 30's after that and then that's it). Once I naively, not wanting to snort so much powder since it wasn't brand name Dilaudid but some generic hydromorphone pill, and they were 1mg, from my dentist, I ate 12 of 'em and it did nothing.

Hydrocodone's way of being so balanced and also very orally bio-available, is not something to hinder, like those who do it with codeine and wonder why it doesn't help much at all (including myself when I was told I would be put on a treatment of CodeineContins 150 and a week later 200mg and have that every day for good while, since the specialist I saw thought it was way too dangerous to do surgery in that area (trigeminal nerve area/right above the jaw where tons of nerves come out from the back of the neck).

 

[THE_REAL_OBLIVION]

Found the answer re: triazolam, it works, a lot, especially if you have 2-3 full glasses of white gfj. https://www.ncbi.nlm.nih.gov/pubmed/11009051 N.B. Chewing and then subbing the pill gives on a rush similar to opiates...I've had this happen with high quality Etizolam blotter before. It's that strong, and the feeling just doesn't go away 10 seconds after like with Etizolam, it will last a good 5 minutes and then continue on as if you had taken it orally but without the wait. Which is pretty much awesome considering the quantity I have one sole tablet is needed for this to happen, and grapefruit eaten before one or two, or two tall wgfj glasses.