The market situation surrounding 4-FMA, a synthetic compound often categorized as a designer drug and research chemical, has evolved significantly in recent years. Initially, 4-FMA gained prominence in online communities as a novel psychoactive substance readily available from various vendors on the internet. It was sought after by individuals interested in exploring its potential effects, often described as stimulating and empathogenic.
However, the regulatory landscape concerning research chemicals has been dynamic. Many countries have implemented stricter controls and scheduling of substances like 4-FMA due to safety concerns and potential health risks. Consequently, the availability of 4-FMA for sale has decreased, and several online vendors have yet to offer it.
The dwindling number of sellers and the increased scrutiny from authorities have resulted in a more restricted market for 4-FMA. Buyers looking to purchase this substance now face more significant challenges in finding legitimate sources. Moreover, more comprehensive research on its long-term effects is needed to raise concerns about its safety.
- 1 Summary
- 2 Chemistry
- 3 Pharmacology
- 4 Subjective effects
- 5 Toxicity
- 6 Legal status
- 7 FAQ
- 7.1 1. What is 4-Fluoromethamphetamine (4-FMA)?
- 7.2 2. What are the effects of 4-FMA?
- 7.3 3. Is 4-FMA safe to use?
- 7.4 4. Are there any health risks associated with 4-FMA?
- 7.5 5. Can 4-FMA cause legal issues?
- 7.6 6. Can 4-FMA be used safely with other substances?
- 7.7 7. Is 4-FMA addictive?
- 7.8 8. Is 4-FMA suitable for nootropic or cognitive enhancement purposes?
- 7.9 9. Is there a safe dosage for 4-FMA?
- 8 References
4-Fluoromethamphetamine, commonly referred to as 4-FMA, belongs to the amphetamine class and is a relatively obscure stimulant-entactogen compound. Its chemical structure shares similarities with both 4-FA and methamphetamine, although its exact pharmacological mechanisms remain poorly understood. It is presumed that 4-FMA exerts its effects by increasing the levels of neurotransmitters such as dopamine, norepinephrine, and serotonin in the brain.
The emergence of 4-FMA can be traced back to its first appearance in the Japanese market as a legal high around 2006. Over time, it has been offered online as a research chemical, often alongside other fluorinated amphetamines like 2-FA, 3-FA, and 4-FA. Notably, when the Netherlands banned 4-FA in 2017, 4-FMA gained popularity as a legal alternative due to their similar names and effects. Consequently, the availability of genuine 4-FA decreased as an increasing number of analyzed samples contained 4-FMA and other fluorinated amphetamines in 2018.
User experiences with 4-FMA suggest a combination of traditional stimulant effects akin to amphetamine and empathogenic qualities resembling MDMA. However, it’s important to note that 4-FMA is associated with a higher likelihood of causing side effects such as headaches and cardiovascular issues compared to similar substances.
The limited knowledge regarding 4-FMA’s pharmacology, metabolism, and toxicity highlights the importance of using harm-reduction practices when considering its use. Its potential for dependence, abuse, and adverse health effects underscores the need for caution and responsible usage.
|CAS Number||351-03-1 |
|CompTox Dashboard (EPA)||DTXSID60874103|
|Chemical and physical data|
|Molar mass||167.227 g·mol−1|
4-Fluoromethamphetamine, commonly abbreviated as 4-FMA, belongs to the synthetic amphetamine family. Within this chemical class, molecules share a core structure comprising a phenethylamine base, characterized by a phenyl ring connected to an amino (NH2) group via an ethyl chain, with an additional methyl substitution at the Rα position. The term “amphetamine” is derived from the abbreviated name for alpha-methylphenethylamine.
What sets 4-fluoromethamphetamine apart is the presence of a fluorine atom at the R4 position of its phenyl ring. This unique feature distinguishes it as a fluorinated derivative of methamphetamine.
Much like its structural counterpart, 4-FA, 4-fluoromethamphetamine is believed to function as both a releasing agent and reuptake inhibitor for dopamine, serotonin, and norepinephrine neurotransmitters. At lower doses, it exhibits stimulating effects reminiscent of amphetamines. At the same time, at higher dosages (typically exceeding 125mg), it is reported to produce more euphoric and entactogenic effects akin to MDA, an empathogen.
Researchers have identified certain similarities in the “Serotonin Release” mechanisms of 4-FMA when compared to other popular empathogens like MDA, 4-methylmethcathinone, and 4-fluoroamphetamine.
The mode of action for 4-FMA involves increasing the levels of norepinephrine, dopamine, and serotonin neurotransmitters in the brain, particularly at higher doses. This is achieved by binding to and partially obstructing the transporter proteins responsible for clearing these monoamines from the synaptic cleft. Consequently, dopamine, norepinephrine, and serotonin accumulate in various brain regions, including reward pathways, resulting in stimulating, euphoric, and entactogenic effects.
It’s worth noting that 4-FMA possesses CYP450 inhibitory properties, which can impact the metabolism of methamphetamine. This inhibition can lead to increased potency, extended duration, heightened systemic toxicity, and reduced cellular toxicity when methamphetamine is co-administered with 4-FMA.
In lower doses, 4-FMA has been reported to exhibit suboptimal nootropic effects for general productivity. However, this usage is strongly discouraged due to the increased risk of neurotoxicity and other potentially harmful side effects. This caution stems from the understanding that 4-FMA shares similarities with MDA and falls into the entactogen category. Frequent use of entactogens is generally considered risky, and it is unwise to take “microdoses” below the minimum threshold required to induce a full “roll” characteristic of entactogens. At higher doses, 4-FMA is known to become dysfunctional and recreational, often characterized by scattered euphoria and stimulation.
Similar to substances like MDA, MDMA, and 4-FA, which elicit pleasurable tactile “roll”-like sensations often associated with serotonin release, 4-FMA has been reported to induce comparable entactogenic effects in addition to traditional stimulant effects. However, some reports suggest that it is accompanied by a higher incidence of side effects and physical strain compared to other fluorinated amphetamines, which may explain its relative lack of popularity and availability.
Disclaimer: The effects listed below are based on anecdotal user reports and the subjective analyses of contributors to the Subjective Effect Index (SEI) at PsychonautWiki. These effects should be approached with caution and skepticism.
It’s important to note that the manifestation of these effects may not be consistent or predictable, and higher doses are more likely to induce the full spectrum of products, including potential adverse outcomes such as addiction, severe injury, or even death ☠.
- Stimulation – The stimulation from 4-FMA is described as a blend of typical entactogen and methamphetamine-like stimulation.
- Tactile enhancement – Relative to other fluorinated amphetamines like 2-FA or 3-FA, this effect is notably distinct.
- Physical euphoria – The intensity of this effect is significantly higher compared to its physical stimulation.
- Bodily control enhancement
- Stamina enhancement
- Pupil dilation
- Appetite suppression
- Orgasm suppression
- Dehydration
- Increased perspiration
- Increased bodily temperature
- Increased heart rate
- Temporary erectile dysfunction
- Teeth grinding
- Vibrating vision
- Restless leg syndrome
- Tremor – Notably present at doses exceeding 150mg
- Muscle contractions
- Dizziness
- Abnormal heartbeat
- Euphoria – Occurs as waves of joy that intermittently intensify and diminish, primarily at dosages above 100mg.
- Empathy, affection, and sociability enhancement – Reports on the extent of this effect vary, with some comparing it to 4-FA and others to MDMA.
- Immersion enhancement
- Novelty enhancement
- Increased music appreciation
- Motivation enhancement
- Delusion – Like many potent stimulants, 4-FMA may induce delusional ideation, although the context of these delusions is not entirely clear.
- Ego inflation – Some users report that this aspect is distinct, although its comparison to other substituted and non-substituted amphetamines is uncertain.
- Stamina enhancement
- Thought acceleration
- Focus enhancement
- Analysis enhancement
- Increased libido
- Time distortion – Characterized by a perception of time passing faster than usual when sober.
- Compulsive redosing
- Paranoia – As with most strong stimulants, 4-FMA has the potential to induce paranoia, though the extent and conditions under which it occurs remain uncertain.
- The comedown effects experienced as a stimulant’s effects wane are often adverse and uncomfortable compared to the peak experience. These typically include:
- Cognitive fatigue
- Motivation suppression
- Thought deceleration
- Suicidal ideation
Do not use 4-FMA if you have a history of heart-related issues or experience severe headaches after its use. Recent reports from Trimbos-instituut and Nationaal Vergiftigingen Informatie Centrum (NVIC) have detailed cases of strokes occurring after increased usage of the closely related analog 4-FA. There is no reason to believe that this does not apply to 4-FMA as well. Alongside common amphetamine-like effects (agitation, anxiety, tachycardia, hypertension, chest pain, and others), serious cardio- and cerebrovascular complications have been reported, including irregular heart rhythms (sinus arrhythmia, ventricular extrasystoles or bigeminy), and acute cardiac failure. While a direct causal relationship has not been confirmed, any occurrence of severe headaches and lateralization following 4-FA or 4-FMA usage warrants immediate medical evaluation at an emergency department.
The toxicity and long-term health effects of recreational 4-FMA use have not been scientifically studied, and the precise toxic dosage remains unknown due to its limited history of human usage. Anecdotal evidence suggests that trying this substance at low to moderate doses by itself and using it sparingly does not appear to result in adverse health effects, although no guarantees can be made.
The LD50 (mouse; i.p.) of 4-FMA remains unknown. While 4-FA does not induce long-lasting depletion of brain serotonin, unlike MDMA or its analogs 4-CA and 4-BA, it is uncertain whether this also applies to 4-FMA.
It’s essential to be aware that 4-FMA can be particularly caustic compared to other compounds and may cause chemical burns in the nasal passage and throat when insufflated.
Using harm reduction practices is strongly recommended when using this substance.
Tolerance and Addiction Potential
Like other stimulants, chronic use of 4-FMA can be moderately addictive, with a high potential for abuse and the potential to lead to psychological dependence in certain users. Those who become addicted may experience cravings and withdrawal effects upon discontinuation.
Tolerance to many of the effects of 4-FMA develops with prolonged and repeated use. Users may need to consume increasingly higher doses to achieve the same impact. It typically takes about 3 to 7 days for the tolerance to be reduced by half and 1 to 2 weeks to return to baseline (in the absence of further consumption). Tolerance for the entactogenic effects may take a more extended period to reduce. Importantly, 4-FA’s usage results in cross-tolerance with all dopaminergic stimulants, meaning that after consuming 4-FMA, all stimuli will have a reduced effect.
Abusing substances within the amphetamine chemical class at high doses and for extended periods can potentially lead to stimulant psychosis, characterized by symptoms like paranoia, hallucinations, or delusions. Approximately 5–15% of users may fail to recover from amphetamine abuse-induced psychosis fully. Antipsychotic medications have been shown to effectively alleviate acute amphetamine psychosis symptoms, according to one trial. Psychosis very rarely arises from therapeutic use.
Warning: Many psychoactive substances, while individually reasonably safe, can become hazardous and even life-threatening when combined with specific other substances. The following list outlines some known dangerous interactions, although it may not cover all possibilities.
Always conduct independent research (e.g., Google, DuckDuckGo, PubMed) to ensure the safety of combining two or more substances. Some interactions are sourced from TripSit.
- Alcohol: Combining alcohol with stimulants is considered risky because it diminishes alcohol’s sedative effects, potentially leading to excessive drinking, liver damage, and dehydration.
- GHB/GBL: Stimulants may enhance the sedative effects of GHB/GBL, potentially leading to respiratory arrest if the stimulant’s effects wear off first.
- Opioids: Stimulants can raise respiration rates, allowing for higher opioid doses. If the stimulant’s effects wear off first, opioid overdose and respiratory arrest may occur.
- Cocaine: Combining cocaine and amphetamines can lead to cardiac effects due to serotonin-related valvulopathy, increasing the risk of heart issues.
- Cannabis: Stimulants may elevate anxiety levels, potentially leading to thought loops and paranoia during cannabis use.
- Caffeine: Combining stimulants like 4-FMA with caffeine may strain the heart, potentially causing anxiety and physical discomfort.
- Tramadol: Both substances can raise the risk of seizures, mainly when used together.
- DXM: Combining DXM and stimulants may lead to panic attacks and more severe heart problems.
- Ketamine: Amphetamine and ketamine together can result in psychoses resembling schizophrenia, potentially characterized by thought disorders and positive symptoms.
- PCP and Methoxetamine: These substances may raise the risk of tachycardia, hypertension, and manic states when combined with stimulants.
- Psychedelics: Combining stimulants with psychedelics can increase the risk of anxiety, paranoia, and thought loops.
- Specific substances like 25x-NBOMe, 2C-T-x, 5-MeO-xxT, DOx, and aMT may have unique interactions or increased risks.
- MAOIs: MAO-B inhibitors can potentiate phenethylamines unpredictably, while MAO-A inhibitors can lead to hypertensive crises when combined with amphetamines.
Australia: In Australia, 4-FMA is categorized as a Schedule 9 prohibited substance under the Poisons Standard (February 2021). A Schedule 9 substance is defined as a substance that may be susceptible to abuse or misuse, and its manufacture, possession, sale, or use is generally prohibited by law. Exceptions are granted for medical or scientific research, as well as for analytical, teaching, or training purposes, subject to approval from Commonwealth and State or Territory Health Authorities.
Austria: In Austria, 4-FMA is illegal to possess, produce, and sell under the Neue-Psychoaktive-Substanzen-Gesetz Österreich (NPSG).
Canada: In Canada, 4-FMA is classified as a Schedule I substance since it is considered an analog of Amphetamine.
China: As of October 2015, China has designated 4-FMA as a controlled substance.
Germany: In Germany, 4-FMA has been regulated under Anlage II BtMG (Narcotics Act, Schedule II) since July 26, 2012. It is unlawful to manufacture, possess, import, export, purchase, sell, procure, or dispense 4-FMA without the appropriate licensing.
New Zealand: 4-FMA is classified as a Schedule 3 controlled substance in New Zealand due to its status as an amphetamine analog.
Switzerland: 4-FMA is categorized as a controlled substance and is listed explicitly under Verzeichnis E in Switzerland.
United Kingdom: In the United Kingdom, 4-FMA is classified as a Class A drug according to the Misuse of Drugs Act. It falls under the provisions of the 1977 amendment to the Misuse of Drugs Act of 1971.
Italy: 4-FMA is designated as a Schedule I controlled substance in Italy.
1. What is 4-Fluoromethamphetamine (4-FMA)?
4-Fluoromethamphetamine (4-FMA) is a synthetic compound belonging to the substituted amphetamine family. It is chemically related to amphetamines like methamphetamine and is structurally similar to other fluorinated amphetamines.
2. What are the effects of 4-FMA?
The effects of 4-FMA can vary depending on the dosage and individual factors. In general, it may produce stimulant-like results at lower doses and entactogen-like effects similar to MDA at higher doses. These effects may include stimulation, euphoria, enhanced tactile sensations, increased sociability, and heightened alertness.
3. Is 4-FMA safe to use?
The safety of 4-FMA has not been extensively studied, and its long-term health effects have yet to be extensively studied. Anecdotal evidence suggests that moderate use at low to moderate doses may not lead to immediate adverse health effects, but this cannot be guaranteed. It is strongly recommended to use harm reduction practices and approach 4-FMA with caution.
4. Are there any health risks associated with 4-FMA?
There are potential health risks associated with 4-FMA use. These may include cardiovascular complications, such as increased heart rate and blood pressure, as well as headaches, anxiety, and even psychosis in some cases. Additionally, using 4-FMA frequently or at high doses may lead to dependence and withdrawal effects.
5. Can 4-FMA cause legal issues?
The legal status of 4-FMA varies by country. In some places, it is considered a controlled substance and is illegal to possess, produce, or sell. It is essential to be aware of the legal status of 4-FMA in your region to avoid potential legal issues.
6. Can 4-FMA be used safely with other substances?
Combining 4-FMA with other substances, especially alcohol and certain drugs, can be risky and potentially dangerous. It is essential to research potential interactions and exercise caution when using 4-FMA in combination with other substances.
7. Is 4-FMA addictive?
Like many stimulants, 4-FMA has the potential for abuse and addiction, especially with chronic use. Users may develop tolerance and experience cravings and withdrawal effects when discontinuing use.
8. Is 4-FMA suitable for nootropic or cognitive enhancement purposes?
Using 4-FMA for cognitive enhancement or nootropic purposes is discouraged due to the increased risk of neurotoxicity and other side effects associated with its use. It is not advisable to use it in this manner.
9. Is there a safe dosage for 4-FMA?
Determining a safe dosage for 4-FMA can be challenging due to limited research. Users are encouraged to start with low doses and exercise caution. It is vital to avoid excessive or frequent use to minimize potential health risks.
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