5-APB

The synthesis of 5-APB was first reported by a team led by the medicinal chemist and psychedelic researcher David E. Nichols at Purdue University. They were examining the role of the MDA dioxle ring structure in interacting with serotonergic neurons. It was also partly an effort to find an alternative to MDMA, which was gaining recognition as a potentially useful adjunct in psychotherapy, but was also being linked to neurotoxic effects.^[1]

Human usage was not documented until 2010, when it emerged for sale on the research chemical market. It was particularly prominent in the UK "legal highs" market, where it was sold under the name "Benzofury".^{[citation needed]}

On June 10, 2013 5-APB and a number of analogues were classified as Temporary Class Drugs in the UK following an ACMD recommendation.^[3] On November 28, 2013 the ACMD recommended that 5-APB and related benzofurans should become Class B, Schedule 1 substances. On March 5, 2014 the UK Home Office announced that 6-APB would be made a class B drug on 10 June 2014 alongside every other benzofuran entactogen and many structurally related drugs.^[4]

5-(2-aminopropyl)benzofuran, also known as 5-APB, is a benzofuran and phenethylamine, meaning it has an ethylamine chain and a furan ring attached to the core benzene ring. It can also be classified as an amphetamine derivative because the ethylamine chain is alpha methylated. Molecules of the amphetamine class contain a phenethylamine core featuring a phenyl ring bound to an amino (NH2) group through an ethyl chain with an additional methyl substitution at R_α. The oxygen in the furan ring is placed at the 5 position, which generally constitutes more stimulating effects than when the oxygen is placed at the 6 position, which is usually described as being more psychedelic in effects. 5-APB is commonly found as the succinate and hydrochloride salt.^{[citation needed]} The hydrochloride salt is 10% more potent by mass so doses should be adjusted accordingly.

5-APB is a triple reuptake inhibitor for norepinephrine, dopamine and serotonin as well as being an agonist for the 5-HT_2A and 5-HT_2B receptors.^[5][6] It has also been speculated that 5-APB acts as a releasing agent for the previously mentioned neurotransmitters.

This means it effectively boosts the levels of the serotonin, norepinephrine and dopamine neurotransmitters in the brain by binding to and partially blocking the transporter proteins that normally remove those monoamines from the synaptic cleft. This allows dopamine and norepinephrine to accumulate within the brain, resulting in stimulating and euphoric effects.

Disclaimer: The effects listed below cite the Subjective Effect Index (SEI), an open research literature based on anecdotal user reports and the personal analyses of PsychonautWiki contributors. As a result, they should be viewed with a healthy degree of skepticism.

It is also worth noting that these effects will not necessarily occur in a predictable or reliable manner, although higher doses are more liable to induce the full spectrum of effects. Likewise, adverse effects become increasingly likely with higher doses and may include addiction, severe injury, or death ☠.

Experience reports

Anecdotal reports which describe the effects of this compound within our experience index include:

Additional experience reports can be found here:

• Erowid Experience Vaults: 5-APB

The toxicity and long-term health effects of recreational 5-APB use do not seem to have been studied in any scientific context and the exact toxic dosage is unknown. This is because 5-APB has very little history of human usage.

Anecdotal evidence from people who have tried 5-APB within the community suggest that there do not seem to be any negative health effects attributed to simply trying this drug at low to moderate doses by itself and using it sparingly (but nothing can be completely guaranteed).

5-APB's high affinity for the 5-HT2b receptor makes it likely that 5-APB would be cardiotoxic with long-term use, as seen in other 5-HT2B agonists such as fenfluramine and MDMA.

It is strongly recommended that one use harm reduction practices when using this substance.

Tolerance and addiction potential

As with other stimulants, the chronic use of 5-APB can be considered moderately addictive with a high potential for abuse and is capable of causing psychological dependence among certain users. When addiction has developed, cravings and withdrawal effects may occur if a person suddenly stops their usage.

Tolerance to many of the effects of 5-APB develops with prolonged and repeated use. This results in users having to administer increasingly large doses to achieve the same effects. After that, it takes about 3 - 7 days for the tolerance to be reduced to half and 1 - 2 weeks to be back at baseline (in the absence of further consumption). 5-APB presents cross-tolerance with all dopaminergic stimulants, meaning that after the consumption of 5-APB all stimulants will have a reduced effect.

Psychosis

Abuse of compounds within the amphetamine chemical class at high dosages for prolonged periods of time can potentially result in a stimulant psychosis that may present with a variety of symptoms (e.g., paranoia, hallucinations, or delusions). A review on treatment for amphetamine, dextroamphetamine, and methamphetamine abuse-induced psychosis states that about 5–15% of users fail to recover completely. The same review asserts that, based upon at least one trial, antipsychotic medications effectively resolve the symptoms of acute amphetamine psychosis. Psychosis very rarely arises from therapeutic use.

Dangerous interactions

Warning: Many psychoactive substances that are reasonably safe to use on their own can suddenly become dangerous and even life-threatening when combined with certain other substances. The following list provides some known dangerous interactions (although it is not guaranteed to include all of them).

Always conduct independent research (e.g. Google, DuckDuckGo, PubMed) to ensure that a combination of two or more substances is safe to consume. Some of the listed interactions have been sourced from TripSit.

• 25x-NBOMe & 25x-NBOH - 25x compounds are highly stimulating and physically straining. Combinations with 5-APB should be strictly avoided due to the risk of excessive stimulation and heart strain. This can result in increased blood pressure, vasoconstriction, panic attacks, thought loops, seizures, and heart failure in extreme cases.
• Alcohol - Combining alcohol with stimulants can be dangerous due to the risk of accidental over-intoxication. Stimulants mask alcohol's depressant effects, which is what most people use to assess their degree of intoxication. Once the stimulant wears off, the depressant effects will be left unopposed, which can result in blackouts and severe respiratory depression. If mixing, the user should strictly limit themselves to only drinking a certain amount of alcohol per hour.
• DXM - Combinations with DXM should be avoided due to its inhibiting effects on serotonin and norepinephrine reuptake. There is an increased risk of panic attacks and hypertensive crisis, or serotonin syndrome with serotonin releasers (MDMA, methylone, mephedrone, etc.). Monitor blood pressure carefully and avoid strenuous physical activity.
• MDMA - Any neurotoxic effects of MDMA are likely to be increased when other stimulants are present. There is also a risk of excessive blood pressure and heart strain (cardiotoxicity).
• MXE - Some reports suggest combinations with MXE may dangerously increase blood pressure and increase the risk of mania and psychosis.
• Dissociatives - Both classes carry a risk of delusions, mania and psychosis, and these risk may be multiplied when combined.
• Stimulants - 5-APB may be dangerous to combine with other stimulants like cocaine as they can increase one's heart rate and blood pressure to dangerous levels.
• Tramadol - Tramadol is known to lower the seizure threshold^[7] and combinations with stimulants may further increase this risk.

• MAOIs - This combination may increase the amount of neurotransmitters such as dopamine to dangerous or even fatal levels. Examples include syrian rue, banisteriopsis caapi, and some antidepressants.^[8]

Serotonin syndrome risk

Combinations with the following substances can cause dangerously high serotonin levels. Serotonin syndrome requires immediate medical attention and can be fatal if left untreated.

• MAOIs - Such as banisteriopsis caapi, syrian rue, phenelzine, selegiline, and moclobemide.^[9]
• Serotonin releasers - Such as MDMA, 4-FA, methamphetamine, methylone and αMT.
• SSRIs - Such as citalopram and sertraline
• SNRIs - Such as tramadol and venlafaxine
• 5-HTP

• Brazil: Possession, production and sale is illegal as it is listed on Portaria SVS/MS nº 344.^[10]
• Germany: 5-APB is controlled under Anlage II BtMG (Narcotics Act, Schedule II)^[11] as of July 17, 2013.^[12] It is illegal to manufacture, possess, import, export, buy, sell, procure or dispense it without a license.^[13]
• Japan: 5-APB is a controlled substance in Japan effective September 16th, 2015.^[14]
• The Netherlands: 5-APB is currently legal, but it is part of a substance group that may be banned soon as part of a recently passed law on New Psychoactive Substances (NPS). ^[15]
• Switzerland: 5-APB is a controlled substance specifically named under Verzeichnis E.^[16]
• United Kingdom: 5-APB is a Class B drug.^{[citation needed]}
• United States: 5-APB could be considered an analogue of MDA and therefore would be covered under the Federal Analogue Act if intended for human consumption.^{[citation needed]}

• Responsible use
• Designer drug
• Entactogen
• Stimulant
• 5-MAPB
• 6-APB
• MDA

• 5-APB (Wikipedia)
• 5-APB (Isomer Design)

Community

• The Big and Dandy 5-APB Thread (Bluelight)

• Greene, S. L. (2013). Benzofurans and benzodifurans. In Novel Psychoactive Substances (pp. 383-392). https://doi.org/10.1016/B978-0-12-415816-0.00016-X