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RCs 2-FMA & 4-FA cross-tolerance?

HighestWhenLow

Bluelighter
Joined
Dec 11, 2012
Messages
84
Location
Neither here nor there
Hello all, I'm looking for some info regarding potential cross-tolerance between the fluorinated amphetamines 2-FMA and 4-FA and to what extent such cross tolerance exists. My instinct (purely speculative of course) tells me that some cross tolerance most likely exists because of their structural similarity and the fact that both act on dopamine & norepinephrine, but I would also guess that cross tolerance might not be too significant because of 4-FA's significant serotogenic qualities and 2-FMA's complete lack of serotonin action (as far as I can tell from personal experience, anecdotal reports and some speculation of 2-FMA's affinity for DA/NE/5HT receptors I read in another BL thread).

So really, my question to any informed bluelighters is if using functional, not recreational doses of 2-FMA (40-60mg/day spread out over multiple doses) on 3 or 4 weekdays of a given week would damper the empathic, serotogenic effects of a recreational 4-FA dose that Saturday (note that I would not use 2-FMA the same day).

Right now I'm thinking the 2-FMA may diminish the DA/NE effects of 4-FA but would not significantly affect the serotonin release caused by 4-FA. However, my knowledge on this topic is pretty basic and I could be totally misguided in my assumptions, so can anyone more knowledgeable weigh in on this issue?

Thanks all, peace & love

- HWL
 
My instinct (purely speculative of course) tells me that some cross tolerance most likely exists because of their structural similarity and the fact that both act on dopamine & norepinephrine, but I would also guess that cross tolerance might not be too significant because of 4-FA's significant serotogenic qualities

That's pretty much on the money. Although 2-FMA, like methamphetamine, actually does release serotonin its effects are not as significant as 4-FA.
 
Thanks for the response, I wouldn't have guessed 2-FMA releases much serotonin based on subjective experiences. I'm still very curious as to how much or how little 2-FMA acts on serotonin.My guess as to 2-FMA's degree of serotonin release is based on the following speculative in vitro potency of inhibition of monoamine uptake in nano-moles of 2-FMA:

DA : 20, NE : 16, 5-HT : 750

This speculation was based on the known figures for 4-FA, 3-FA, d-amphetamine and methamphetamine, which are:

4-FA
DA : 33.3, NE : 18.3, 5-HT : 218

3-FA
DA : 24.2, NE : 16.1, 5-HT : 1937

Dextroamph
DA : 8.0, NE : 7.2, 5-HT : 1756

Meth :
DA : 4.67, NE : 6.47, 5-HT : 116

A few questions here:

1. Are the figures for 4-FA, 3-FA, meth and d-amp accurate?
2. Are the suggested numbers for 2-FMA reasonable this evidence?
3. And if so, how significant would the cross tolerance be between 2-FMA and 4-FA with regards to serotonin?

Sorry for all the specific questions, I've just searched the web high and low for all of this info for 2-FMA and there's almost no trace of it from any credible source, and virtually nothing scientific.

Any input is much appreciated.

-HWL
 
Thanks for the response, I wouldn't have guessed 2-FMA releases much serotonin based on subjective experiences. I'm still very curious as to how much or how little 2-FMA acts on serotonin.My guess as to 2-FMA's degree of serotonin release is based on the following speculative in vitro potency of inhibition of monoamine uptake in nano-moles of 2-FMA:

DA : 20, NE : 16, 5-HT : 750

This speculation was based on the known figures for 4-FA, 3-FA, d-amphetamine and methamphetamine, which are:

4-FA
DA : 33.3, NE : 18.3, 5-HT : 218

3-FA
DA : 24.2, NE : 16.1, 5-HT : 1937

Dextroamph
DA : 8.0, NE : 7.2, 5-HT : 1756

Meth :
DA : 4.67, NE : 6.47, 5-HT : 116

A few questions here:

1. Are the figures for 4-FA, 3-FA, meth and d-amp accurate?
2. Are the suggested numbers for 2-FMA reasonable this evidence?
3. And if so, how significant would the cross tolerance be between 2-FMA and 4-FA with regards to serotonin?

Sorry for all the specific questions, I've just searched the web high and low for all of this info for 2-FMA and there's almost no trace of it from any credible source, and virtually nothing scientific.

Any input is much appreciated.

-HWL

where did you get those figures? this sounds about right to me, as i find a combination of d-amphet salts and 4-FA to create a nice well rounded feeling.
 
Those numbers are Ki or binding coefficients, lower numbers = more effective binding = (generally) more effective at causing release

Your speculative figures, how did you derive them? There are actual accurate figures out there for the fluoromethamphetamines I am sure.
 
Theres a list here on wikipedia with seemingly reliable sources. http://en.wikipedia.org/wiki/Releasing_agent Not sure where the others might have come from, probably the same place but different page.

But look:

4-Fluoroamphetamine NE:28 DA:51.5 5HT:939

Completely different than that which is above.

Again from experience, there doesn't seem to be any cross tolerance.
 
Those numbers are Ki or binding coefficients, lower numbers = more effective binding = (generally) more effective at causing release

Your speculative figures, how did you derive them? There are actual accurate figures out there for the fluoromethamphetamines I am sure.

Theres a list here on wikipedia with seemingly reliable sources. http://en.wikipedia.org/wiki/Releasing_agent Not sure where the others might have come from, probably the same place but different page.

But look:

4-Fluoroamphetamine NE:28 DA:51.5 5HT:939

Completely different than that which is above.

Again from experience, there doesn't seem to be any cross tolerance.

To answer both of you: I didn't derive the speculative figures myself, I got them from this post in the 2-FMA Megathread:

I believe, 2-FMA indeed binds to SERT. In order to underline my statement I've collected some info from papers regarding the effects of X-F(M)A's.
I've made a comparison chart with gathered scientific data coupled with personal experience.
Unfortunately, I cannot say anything to the in vitro potency of 2-FMA but I tried to derive data from experience in the end.
Would be great if someone could complement the summary with data for 2-FMA.


potency expressed in mean of self-administered dose in mg per kilogram body weight (tested on apes), that is sufficient as cocaine replacement:
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

4-FA

0.32

3-FA

0.23

Meth-A

0.10

In vitro potencies of inhibition of monoamine uptake in nano-moles (the lower the stronger) :
-------------------------------------------------------------------------------------------------------------------------------------------------------

4-FA

DA : 33.3, NE : 18.3, 5-HT : 218

3-FA

DA : 24.2, NE : 16.1, 5-HT : 1937

Dextroamph

DA : 8.0, NE : 7.2, 5-HT : 1756

Meth :

DA : 4.67, NE : 6.47, 5-HT : 116

LD_50s of fluoroamphs vs. amph in mice :
--------------------------------------------------------------------

2-FA

100mg/kg

4-FA

46mg/kg

d-methamphetamine

55mg/kg

d-amphetamine

98mg/kg


Correlations between experience and scientifically obtained effects profile (speculation) :

4-FA :

Is far less potent but has a worse LD50 than d-Amph and d-meth -> overall higher toxicity. For me it also feels very draining the next day (if more than 80mg is consumed).
4-FA has half of the potency of Meth regarding 5-HT reuptake inhibition. The DA/5-HT-ratio of 0,15, which is the highest in the above data, underlining it is better suited for social settings
than any of the other compounds. 4-FA is the most similar compound to Meth of the above, if you can say that, because DA inhibition it lacks significantly.

3-FA :

3-FA is less potent but has a similar effect on monoamine reuptake as d-Amph. If you just take the above data into account, the effects shall be the same as d-Amph with a slightly better DA/NE-ratio, meaning less jittery, but a slightly worse DA/5-HT-ratio, meaning supposedly more head fog but perhaps the activity on 5-HT is too weak anyway. Also 3-FA was considered the most effective cocaine replacement of every substituted amphetamine (including meth and d-amph). That means that it is highly addictive/moreish.

Meth :

Is somewhat outstanding, as the DA/NE-ratio is <1 (more dopamine, less norepinephrine) . That would explain the absence of side effects, that users describe and also the addiction potential. The pretty high DA/5-HT-ratio could also be a contributor for that. The high DA/5-HT-ratio is responsible for the depression when in withdrawal.

2-FMA :

Is not mentioned above. But I guesstimate from the effects that its profile is something like that :

2-FMA

DA : 20, NE : 16, 5-HT : 750

For my taste there is too much serotonine action going on, making the effects unpredictable. Also it has completely different effects if you change the ROA. Insufflated it is okay, but orally
it has too much SRI - qualities ! Please correct the data, if there are errors. If you can provide data on 2-FMA, it would be great.

@ Seiko: I scoured the web to exhaustion and found no concrete figures for 2-FMA specifically, but hopefully there are some out there even if I couldn't track em down. Do you think an estimate for 2-FMA could be made from the figures of other fluoromethamphetamines, maybe 4-FMA, which seems to be the most popular of the fluromethamps? All I could find specifically on 2-FMA was this: http://ewsd.wiv-isp.be/Publications%20on%20new%20psychoactive%20substances/Mephedrone/Camilleri_2010_Chemical%20analysis%20of%20four%20capsules%20containing%20the%20controlled%20substance.pdf. The citations for the works cited in this section are these:

[6] P. Rosner, B. Quednow, U. Girreser, T. Junge, Isomeric, Fluoro-methoxy-phenylalkylamines: a new series of controlled-substance analogues (designer drugs),
Forensic Sci. Int. 148 (2005) 143–156.

[20] G.L. Alexander, Characterisation of aromatic fluoro-analogs of phenylacetone,
amphetamine and methamphetamine, Microgram XXVII 8 (1994) 268–275.

The section relevant to 2-FMA is this:

"Many fluoroamphetamines, including 2-fluoromethamphetamine, have been characterised by both GCMS and NMR [6,20]. Previous reporting has demonstrated that each of the three possible fluoromethamphetamine regioisomers has different retention times [20] however, it has been reported that there is only a slight difference between the retention times of 3- and 4- fluoroamphetamine [6]. The Kovats retention index of 2-fluoroamphetamine shows baseline separation from the other two regioisomers [6]. Initially, without a reference standard or NMR, this compound was suspected to be 4 fluoromethamphetamine and reported to consumers as such through the hastily prepared posting of a preliminary report on the Internet-based drug discussion forum ‘‘Bluelight’’ [14]. Subsequently, 2-fluoromethamphetamine and 4-fluoromethamphetamine standards were obtained and a retention time match and resolution from 4-fluoromethamphetamine (2.62 min) confirmed 2-fluoromethamphetamine (2.56 min) within the capsule."

Kinda funny that it references BL haha. But I don't know enough to make much of this passage, anyone a little more knowledgeable able to shed some light on it?
 
Last edited:
UPDATE:

I found the answer to my original question yesterday through personal experience. I found that, for me personally, there appears to be significant cross tolerance between 2-FMA and 4-FA, at least when used on the same day.

I used 70mg 2-FMA broken up into 4 doses spread throughout the day for productivity purposes, and about 3 hours after my last 2-FMA dose I took 110mg 4-FA orally, which is my go-to recreational dose. I experienced absolutely NONE of the serotogenic, empathic qualities 4-FA usually has, and only felt a boosted speedy feeling, not unpleasant but far short of what I was expecting.

The reduction in effects was far greater than anything I've experienced prior with 4-FA. Even when using it for multiple consecutive days, 4-FA has never failed to provide any mood-boosting effects whatsoever. The dramatic spike in tolerance I experienced may have been due to dosing both substances on the same day, and sometime in the future I may report back on the effectiveness of 4-FA taken the day after 2-FMA but not on the same day.
 
Would the dopamine release triggered by 2-FMA inhibit the serotogenic effects of 4-FA? I'm definitely no chemist so I could be asking an obvious question, but I would have thought that my serotonin molecules would be relatively intact from just 2-FMA, which is why I'm still a little puzzled as to why my experience seemed to completely lack any 5HT activity whatsoever. Thanks for your input
 
I'm not suggesting that it inhibited them, but mabye 2fma synergized with the 4fa and created a strong domapinergic activity that just outshined any potential 5ht activity. The empathic effects of 4fa are subtle compared to other serotonin releasers.
 
^^^
Ahhh, makes sense now, thanks to both of you for your responses. In any case, I'll be able to comment on the cross-tolerance of 2-fma and 4-fa when taken within a couple days of each other but not the same day very soon, so I guess I'll discover the answer for myself. I'll be sure to report back though so there's some anecdotal points of reference for anyone else asking the same question in the future.
 
UPDATE:

I found the answer to my original question yesterday through personal experience. I found that, for me personally, there appears to be significant cross tolerance between 2-FMA and 4-FA, at least when used on the same day.

I have to retract this claim for cross-tolerance between 2-FMA and 4-FA. Last night I took my usual recreational dose of 4-FA (110mg) and gave a friend the same. I had used 2-FMA two days prior to this, and my friend had never used 2-FMA and only used 4-FA once a month ago. Both of us felt very little from the 4-FA, and definitely no empathogenic effects. Note that the previous time we took 4-FA together (his first time) we both had fantastic experiences with very noticeable serotonin activity. I have to conclude that my current batch of 4-FA is of sub-par quality compared to the batch I had a month ago.

Additionally, I wanted to note that 2-FMA didn't seem to damper the empathic/entactogenic effects of methylone in the slightest. We both dosed 220mg of methylone at T+3:00 after taking the 4-FA and went from mild stimulation to an intensely amazing experience that made for one of the most fun nights in recent memory, I've been light-hearted and smiling all day just from the memory of the experience, and have had absolutely no hangover symptoms. Complete and beautiful afterglow :)
 
i wonder if the sequence of dosing matters as well, like say you take 4fa one day and decide for 2fma the next... i suspect some cross tolerance to be present, as well as increased after effects due to physical exhaustion..
 
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