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RCs Novel opioid 4-Fluoroisobutyrfentanyl (4-FiBF, p-FiBF)

I might try this one out.

My status:

Multiple years, more than a decade on strong MOR agonists. DHC/codeine for a few years, then on to oxy 80s a couple of times a day, before geting my doc to switch me to XR morphine (usually shot at 3-800mg a go) and lower dose oxycodone IR (nominally meant to be 40mg a day, taken in 10mg increments as and how I feel to be requisite.) for breakthrough.


Injury was originally falling on a big spike of broken glass, that went straight into my knee joint, had to break it off and face a several mile WALK to be able to seek medicial aid. And whilst recovering, had the shite luck to get jumped by a pack of 20-odd chavscum, stamped my kneecap in, used it like a fucking trampoline, before beating the absolute everfucking holy shit out of me and leaving me for dead in the street.

Surgery on the knee didn't help, made things worse even, a little, plus left me with some nerve damage that causes constant paraesthesia, spasticity and numbness, icy kind of pain down the side of my leg, gabapentin is far better than opiates to for neuropathic pain, but generally speaking, I still have quite a lot of pain left, and 'off' days when things just get to much to withstand, when my trochanteric bursitis flares up too and I can do nothing but crawl into bed and spend the day whacking morphine and oxy, go to the nearby toilet, and surf the net on my laptop etc.

Fed up with it, I really am. There are few things like intense and chronic pain to wear someone down, to turn someone from a hardened and healthy vital individual to an exhausted shade of their former self.


The docs of course are always very jealously guarding of their script pads where opiods are concerned, and I barely, barely get enough to remain physically functional with what I'm given, and even then I get left in a halfway state, just about maintained, some pain relief, but only enough to keep me more or less mobile if I haven't to travel any distance.

So I'd very much like the option at least, of actually selfcontrolled ability to judge intake, and have the capability available for a severe pain breakthrough med, for when a gram shot of morphine sulfate and a handful of oxy 10 IR caps emptied liberally into the prepping hit still leaves me wanting to curl up and howl, and esp for bursitis flares, those are the fucking very rectal sphincter of the abyss, let alone the crowbegotten PITS. Makes it impossible to lie in any position, back, frontal prone, sides, sat or anything else I can think of for that matter. And can't comfortably stand either for long.

BE EXTREMELY CAUTIOUS if IVing this substance!

The fentanyls, unlike other opioids, cause a specific effect on intravenous administration whereby respiration is temporarily paralyzed for a moment, its not long, but its there, and with additive effects from respiratory depressant effects, especially pronounced with the fentanyls.

This is NOT ordinary, dose-responsive respiratory depressant effect, its specific to the fentanyls as far as I am aware, although wouldn't be too shocked if the thebaine derivative types, etorphine and co, as well as such as the bentley, and knauss opioids do it too, and its specific to injection as the ROA. NOT respiratory depression, and dangerous, or it certainly can be. Don't even think about trying it alone. Make sure to have a sitter thats capable of providing assistance, or at the VERY least, if theres nothing else for it, contacting for emergency medevac.

Got a sod of a morph/oxy tolerance, have tried fent, alfentanil and I forget which but either remi- or su-fentanil. Not the ultrashort acting one, the longer acting of the two, although still really short acting. As well as one other, can't be certain as it was in a presurgical setting, but maybe lofent, name comes to mind for some reason, can't be sure which ones were used on me that time.

Definitely going to give this a go then after all is considered, not for in-out use but for intermittant rec use, and for breakthrough analgesia, when even the biggest syringe in the house cannot contain a sufficient dose of morphine sulfate to alleviate pain fully, well the second biggest, the biggest of all have a couple of feet long wide-bore ID size length of glass volumetric measurement tubing permanently attached to the end in place of a human needle, need a two-handed grip to operate those massive syringes. IMO maybe originally intended for farm animal use perhaps, or enteric tube feeds, etc. for those that cannot now eat by mouth.

Way too big for human use to be within the realms of the possible, and I use them for withdrawing liquids from containers that need to remain as closed off as posible, such as, for the last use I had involved some DIY-ing epoxy-like resin glue, so ended up using di-isocyanates as the crosslinker, and isocyanates.they suck big time, toxicity wise.
Worked well enough, to make some DIY quick and dirty two-part resin glue out from a polyol and a compound containing more than the single isocyanate group, to act by forming urea/amide bonds, resulting in a polyamide.

Worked well enough to have a satisfying conclusion, in which thy labours bear fruit

That's rough man. I often wondered why you got some of the meds you did. I knew you were in pain but I didn't know it could be so bad sometimes as to cause you such intense discomfort/agony.

I might try this one myself. I enjoy morphine but don't have the veins left anymore to shoot any solution over 2 mls. I don't use my groin and have ruined the larger more acssebile veins through years of shooting coke/crack with my h.
This sounds like it could be a good chemical to use iv along with coke or if it is not euphoric enough I might use it rectaly or nassaly once or twice a day as needed to keep withdrawals away until i get onto a methadone programme here.
 
What are the solubility differences between the freebase and maleate?
The maleate form is more soluble in water and the freebase form is more soluble in something like propylene glycol or vegetable glycerine. Does anyone know the oral dose range of what amounts are light, medium, and heavy doses for FIBF?
 
Thank you. That's honestly what I expected, but I wanted to be certain. I haven't tried the 4F-iBF yet, as I need to be cautious where opioids are concerned due to my tendency to go way too far, and with fentanyl and analogs, that's certain death. I want to read a good bit more before trying. I have only tried U-47700 yet, as far as RC op's go.
 
So, I received 1g of 4F-iBF maleate, of which I took Liminality's dosing method of using 25mg per 30ml (I did not add the extra 6ml because I have a 30ml vial). I actually left 0.6ml out of the solution, so that I could dissolve the 25mg in a spoon easily and then pour it into the solution. I am extremely opioid tolerant (by the 3rd day of using U-47700, I was up to 50mg per IV dose). It takes 160mg of oxycodone to do much of anything to me, and I don't use heroin anymore.

Everything seemed to be in order except that I could see particles at the bottom of my vial that I am assuming either; 1. did not dissolve properly, or 2. is a product of an impure batch (the U-47700 was from the same supplier and was very pure.) Any input?

Because of the undissolved substance, I made sure to filter before using. After an allergy test, I first tried 0.1ml IV and felt nothing. I waited about 15min, and then tried 0.2ml and felt nearly nothing. At 0.5ml I got a decent (though not overwhelming by any means) rush, and afterwards I was left with a warm, opioid glow that, as stated by others, was pleasant, but definitely lacking in euphoria. It did not last long, which had to do with the dose. I hadn't reached an amount that would sufficiently affect me.

I have since, over the past 4 hours, used two 1.0ml IV doses, and I am finally at a point where I can say that I am somewhat intoxicated. From what I was lead to believe about the substance, it shouldn't have taken nearly that much, but my tolerance is ridiculous. I am going to restrain from using any more until I come down completely. I am not naive to fentanyl, so I know what the respiratory effects can be like when you fall asleep. I think my next trial is going to be oral or rectal because my veins are too warped for these experiments, and I am looking for something that is a good bit longer lasting and (probably) a lot less dangerous.
 
Nose clogging?

What I received was a white powder made up of small shiny crystals, though it wasn't labeled I was told it was 4-FiBF.

I was looking for the traditional fentanyl characteristics in terms of effects but compared to the BF and FF I had before, both produced anesthetic effects when applied to the mouth, and both has an extremely-Fi similar appearance - both were extremely soft, flakey & sticky. So sticky that 50mg would easily stick to the bag (probably why it can be used transdermal - via the skin).

This 4-FiBF had none of those qualities, rather it wasn't sticky, it was a powder made of very crystalline grains. It didn't have the numbing qualities, maybe 1/10th the numbing, nothing comparable to the previous 2!

I don't inject so I put so on foil and smelt it, upon which I immediately recognized the smell! My hollowed out pen from the previous BF & FF smelt just like that! I got excited and decided to smoke 1-2 hits! It would turn into a yellow blob and if heated continuously it would start to run toward the end, and it wouldn't vaporize as easy rather it would sort of split up from one blob into several that would run into different parts. If heated with the lighter several times, flicking the lighter 2-3 times before it burned it wouldn't do this as much. Even smoked I never got the numbing of the mouth as I did previously! I didn't get a rush either like with FF or BF but I did feel it and felt pretty good.

I decided to snort some and as soon as I snorted my nose would become *very* clogged, so much so that I began suspecting what I had gotten to be U-447700 which is the only chemical that not only fucked my nose good but also made it impossible to breath (even taking 20mg-30mg ephedrine).

After snorting I felt much better, as I take methadone, the withdraws that were supposed to start never did and beside that I felt invigorated mentally as I would have on fentanyl though I felt more sedated than with BF or FF which felt almost like stimulants in effects. I kept doing lines and felt a sting/burn every time I snorted though I didn't really feel the drips.

I get clogged but its de-clogged within 1hr...and its not u4 since I don't experience a craving afterwards, also even though I get my nose as badly clogged it gets unclogged within the hour not within 2-3 days.

Most concerning, I realized that I did 400mg within 24hrs!
Without ever reaching the kind of euphoria or rush that FF or BF provided, and it is noticeably longer lasting than any of the others I've done before. Even longer than fentanyl! I also tried some orally - about 25mg-30mg.
If I had BF or FF 300mg would have lasted me ages!

I was thinking that I got some Acryl or u-447700 though because of the clogging of the nose but I can say for sure its not u-447700 since I've had it and still have some and when I put it on foil it smells the same way MDPV smelt like - that is to say like cum/semen - not joking! Also, my nose was *extremely* clogged on that and it remained so for a good 36hrs-48hrs! Also there was a distinct rush with u-4 with effects over in 45min and a noticeable fiendish feeling after! The powder not only burned more but it also tasted like shit going down/the drips.

Anyone notice the clogging of the nose?

Could it be that what I have is instead Acryl?

So far what I'm reading about 4-FiBF fits the description pretty good, though nobody speaks of the bad nose clogging!
 
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Can someone describe what the withdrawals are like on this substances?
 
I have had a half gram of 4-Meo-bf., it sucks. I had fu-f which I think is great for smoking. Ther e was no use for the former. Anyone know anything about acrtyl -fentanyl, misspelled, or any other analogues available.
 
Please disregard what I said in my post!

I thought that what I had was 4-FiBF but I am now 1000% sure what I received was actually u47!

The reason why I thought it was 4-FiBF is because the vendor that sent this did it as a re-shipment since my original 20g Fu-F ended up being U47. The re-send ended up being a more crystalized version of U47. I smoked it and when smoked it lasts much shorter than any other MOA, but it feels damn toxic that I think brain damage is a very real possibility if not from the molecule itself than from the lack of oxygen to the brain that this produces by constricting/plugging your nose when snorted and smoked doesn't produce much euphoria.

Another reason is because I used the dosages recommended with Fu-F or 4-FiBF so about 10mg-20mg at most, while if I was doing U47 I would line myself up at least 30mg+ so eventually I thought it may be Acryl....all of which were offered by the vendor! However there was 1 constant which I noticed with the 1st batch as well, which is when put on foil, even though this batch had a different taste to it, it wouldn't vaporize off the foil like normal with #4 dope or Fu-F, but always would run off without fully burning in one spot unless you'd flicker the lighter 10 times for 1 hoot. Also its not an anesthetic like Fu-F or BF!

I did this for several days (snorting also) and I was pretty confident it was 4-FiBF b/c I felt it was smooth like hell compared to the tears running down my face after a bump of U47 & I suppose that due to having some methadone in my system, other times numb from a couple drinks, while others maybe from smoking it, I never noticed how much it really hurt!

Until one day when I hadn't taken methadone for 3-4 days & been doing this opioid exclusively, bumps & chasing off foil for about 3-5 days. I had taken a long nap the night before and when I woke up I didn't smoke, instead I snorted. Instantly I couldn't even wait until the drips, before I had my nose running without doing anything, sneezing and huffing like I had ate too much hot souse (sp?). Soon after, I experienced the classic heart palpitations and sweats, like methadone times 100...which happened every time I've snorted U47 and many times if it was the 1st dose of the day, the gastro intestinal system would be so fucked up that I'd go to the washroom to shit like I had diarrhea. While on the toilet seat it would wear off in about a 3-5min period which would be how long it took to feel anything & the reason the pain would subside that quick I'm sure, is because its such a potent painkiller. So much so that on one occasion for the 1st dose of the morning I took 10mg in a gel cap (thinking it was something else) and after waiting about a half hour I lined up 2 bumps of 10mg-15mg. I snorted them, one in each nostril, and I thought to myself 'I finally got what I ordered, this cannot be U47 b/c that shit burns the hell out of your sinuses'....the analgesic effects are that powerful from U47 that 10mg taken 30min prior orally, had completely blocked any pain felt from the same snorting that makes your nose & eyes tear up like a hot pepper x 100!

Since around the beginning of the year what's been going on in the RC scene is that a vast majority of legit vendors that list RCs such as U47 & Fu-F on their site, will take your order for Fu-F but instead they send you U47! This has happened to me from 3-4 different vendors, all of whom were legit, some whom even sent me the 1st time Fu-F but when ordering a larger amount they send U47 in an effort to scheme you or maybe they think they are better protected from the law this way but as long as its not for human consumption the law doesn't discriminate! It really doesn't make sense as they the difference in price between those 2 RCs per gram, isn't *that big* of a difference, that is when you are buying more than a gram or two!

Apologies for making this post so long but hope that others in the same position may have found it useful, in which case it was worth it IMO!
 
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Parafluoroisobutyrfentanyl must be rare as fuck, since i find no experience reports or other information anywhere, which is the same with places selling that incredibly lovely (and incredibly dangerous!!!) substance.

I had the chance to try a sample (50mgs) some months ago but unfortunately never had the chance to aquire more of it, so if no one spreads information about it, at least i can tell a few things for ppl interested in it.

So it is BY FAR (honestly, BY FAR, FAR FAR!!!) the most potent Fentanyl Derivative there is, has an exceptionally long duration and extraordinary broad-spectrum effects-profile and has (at least when dosed rectally) a ridiculously fast onset, which means in detail:

Potency: it's a fuckin' TERMINATOR, honestly... I cannot name detailed numbers, but it's the strongest among all the F-Derivatives, and 1mg means overdose for most ppl (and yes, even those with a high Tolerance to Opioids/Opiates, and i've taken Hydromorphone for the past 7 months and am back to Oxycodone now, as i'm chronic Pain Patient and took doses of 80mg+ HM (plugged) or equivalent doses of Oxy without having ODs, i.e. those are my exceptional recreational doses if used (sparingly) for this purpose. See ONSET for a few other related infos about POTENCY!

Duration: it's hard to determine, but as far as i remember, effects are felt at least till the 6h mark, perhaps even longer (as i don't remember exactly, i won't name detailed numbers, again, as i don't wanna spread false data, so rough estimation is the only thing i can contribute - which is giving a good picture, even if not perfect, about this rare Compound and it's profile). What i can say is, after researching EVERY single one of all of the Fentanyl-Derivative RC Compounds, with the sole exception of the possibly toxic Acryl-Fentanyl (i don't wanna ingest Acryamide, not even in lowish' doses!), that Parafluoroisobutyrfentanyl, had the longest duration of effects compared to the other ones, just as is had the most full, or more precisely, broad...

EFFECTS-PROFILE: As said, PFIBF felt "full", it wasn't as (subjectively felt) good, or full-spectrum Opioid/Opiate-effects providing as my personal Favorite Acetyl-Fentanyl, which had the warmth and subtle euphoria of even classic Opiates like Morphine (to a degree, not totally, but to a degree, at least), but i rate it very high and it felt not sterile, or cold, but somewhat full and absolutely on par with stuff like Hydromorphon/e or Oxycodone (but that's just me, and i should point out that not one of those two provide euphoria to me, that's exceptionally the case in 1/10 times dosing O-DMT or, as it is totally outstanding for it's unrivaled Effects-profile and the sole exception Compound of this Class, which did this more than just once, i.e. providing euphoria (not in-your-face, but through muting my Pain-issues strongly, a subtle, trance-like and impossible to describe feeling of what i would call euphoria). But to feel it's effects, one must (and it's not easy to handle!) dose correctly, and be prepared (to not get wiped-out High-Kick Style) for a very fast...

ONSET: which is (i just dosed rectally) fast as fast can be, and it did hit me not just once like a plank (honestly, it REALLY felt like a plank, full-frontal...) in the face, and even if handled properly i ended two times in the corner of my kitchen, woke up after 2-3hrs as it came on way too fast, or better, way too far as expected (that was the first few times i tried it) and i think, if i remember correcty, it was for sure (!) under a minute, i'd say 30sec. at most, and i do know exactly that i didn't even had the chance to put the syringe and PFIBF containing flask aside, and this means something.

So that's it, i hope it helps someone to see that it's one of the best of this Derivatives, within my personal top 3, but also the most dangerous one to handle, even in the right hands... Stay safe ppl!
 
Creating a homogeneous mixture of two different powders is difficult.
More often than not you will have hot spots.
You have to trust that your supplier used the proper equipment and made no mistakes.
This, in my opinion, increases the risk of overdose not decreases it.

The best way to reduce the risk of overdose is volumetric dosing. Use a liquid To create a solution.

On a side note,
I have mixed feelings about opioids being available freely on the internet. It is great that people who know what they are doing and are possibly in chronic pain have access, but on the other hand, its hard to tell the difference between a capable experienced user and a 15 year old with moms credit card.

Not that my opinion makes a bit of difference in world events...

i asked how to do this properly, concerning the superpotent benzos. my plan was to dissolve the benzo in alcohol, along with inositol, evap the alcohol and chop. which would be a bitch, but there would be no hot spots. i'd really like for someone to write a tek on how to do this right.
 
^Why evaporate the alcohol if you've got a 'olution you can use do dose ?
And imo I would still be concerned about hotspots
 
Anyone know what the method of administration percentages are for any of the fentanyl analogues?..
I can't find any info on doses for the different routes of administration. Two tiny bumps (size of a match head) of white powder insufflated over an hour ago. SWIM is travelling very relaxed, classic opioid-like itches and somnolence. Very smooth.
Nodded off about 6 times during this very short post! Wary of amount to use for IV. Advice greatly appreciated.
 
I can't find any info on doses for the different routes of administration. Two tiny bumps (size of a match head) of white powder insufflated over an hour ago. SWIM is travelling very relaxed, classic opioid-like itches and somnolence. Very smooth.
Nodded off about 6 times during this very short post! Wary of amount to use for IV. Advice greatly appreciated.

We don't use SWIM and eyeballing powerful fentanyl analogs without knowing the dosage will most likely kill you, don't do it! Search for a proper dosage, get a milligram scale and make a solution with like 1mg/1ml
 
We don't use SWIM and eyeballing powerful fentanyl analogs without knowing the dosage will most likely kill you, don't do it! Search for a proper dosage, get a milligram scale and make a solution with like 1mg/1ml
Thanks for your reply kleinerkiffer.
First post on here so I used SWIM just in case, appreciate the head's up.
I know ... *hangs head* - I wouldn't usually try to eyeball something like this but my point scales were recently stolen and I was impatient to try it. Stupid I know. As is feeling like a wee bit more after not quite two hours...
 
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^At least make a solution. If you ordered 1g see it as 1.5g just to be safe (sometimes vendors are generous) and mix it, so you get 1mg/ml or better 0.5mg/ml and proceed as you would with normal fentanyl, so start with 50 microgram and slowly work your way up
 
This is the most frustrating thread - no scratch that - the most frustrating COMPOUND out there regarding the complete lack of information on it

I am stabilised on 110mg/day of methadone & have been on it for a year now

I got some 4-fibf due to its lack of recreational effects & most importantly duration - so that every once in a while on an isolated off day i could use it instead of methadone in order to save a couple days worth

I figured id start with 100ug nasally via 0.1ml nasal sprayer.... if anyone has any guess as to AROUND how much it MAY take to keep me well, id love to hear it

I'll start with 100ug regardless & leave 10-15 mins between redoses to be safe regardless. I dont have a death wish

I'll report back when i get a chance to try it. Wont be for a few weeks at least.

But i have the MALEATE form. If anyone can let me know how saturated of a solution i can make, and any tips to make it dissolve better (besides hot water bath) please tell me!!! I have read that this compound will dissolve 1mg/ml in sterile water alone...?
 
may I point out that waiting only 15 min between doses could be very problematic? this is an unresearched compound (I believe), so in practice, the levels of the drug in your body may be still rising from the first dose when you redose. just feeling that it doesn't get stronger isn't a safe indicator. I think you should wait longer than that, if you want to redose.
 
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