Main: 4-Fluoroamphetamine (4-FA; PAL-303; "Flux", "R2D2"), also known as para-fluoroamphetamine (PFA) is a psychoactive drug and research chemical of the phenethylamine and amphetamine chemical classes. It produces stimulant and possibly entactogenic effects. The usual dosage for individual consumption varies greatly per individual but is typically between 60 and 200 milligrams. 4-FA is a relatively rare drug on the illicit market, although it is sometimes sold as a designer drug along with related analogues such as 2-fluoroamphetamine and 4-fluoromethamphetamine, among others.
The subjective effects of 4-FA include euphoria, increased energy, mood elevation, excessive talking, bruxism (jaw clenching), insomnia and suppressed appetite. 4-Fluoroamphetamine is a potent stimulant and serotonin releaser as with other para-substituted amphetamine derivatives, but is both significantly less potent as a serotonin releaser and much less neurotoxic than related compounds such as parachloroamphetamine and paraiodoamphetamine, with both serotonin-releasing potency and neurotoxicity increasing down the halogen series 4-FA << PCA < PBA < PIA, while conversely the dopamine reuptake inhibition produced by 4-FA is stronger than that of either PCA or PIA. 4-FA also produces less hyperthermia than similar compounds such as PMA, 4-MTA and 4-methylamphetamine, but both hyperthermia and neurotoxicity are still likely to be complications of overdose or excessive use of 4-FA.
4-fluoroamphetamine was banned in Lithuania in July 2009. 4-fluoroamphetamine will be banned in Switzerland the 1st December 2010. 4-fluoroamphetamine is illegal in Sweden.