Baclofen

Baclofen was synthesized in 1962 by Heinrich Keberle at Ciba (pharmaceutical company) in Basel, Switzerland, based on the idea of enhancing the lipophilicity of GABA in order to achieve penetration of the blood-brain barrier.^[3] It was marketed as Lioresal in 1972.^[3]

In his 2008 book, Le Dernier Verre (translated literally as "The Last Glass" and published in English as "The End of my Addiction"), French-American cardiologist Olivier Ameisen described how he treated his alcoholism with baclofen. Inspired by this book, an anonymous donor gave $750,000 to the University of Amsterdam to initiate a clinical trial of high-dose baclofen, which Ameisen had called for since 2004.^[5]

Baclofen is a derivative of γ-aminobutyric acid (GABA), except with a chlorine-substituted phenyl group in the β-position of the molecule.

It has an almost identical chemical structure to F-phenibut (only replacing a fluorine with a chlorine atom in the para-position of the phenyl group).

It is a chiral molecule and thus has two potential configurations as (R)- and (S)-enantiomers.

Baclofen is a white (or sometimes off-white) mostly odorless crystalline powder, with a molecular weight of 213.66 g/mol and it is somewhat soluble in water.

Baclofen produces its effects by activating the GABA_B receptor, similar to the drug phenibut which also activates this receptor and shares some of its effects. Baclofen is postulated to block mono-and-polysynaptic reflexes by acting as an inhibitory ligand, inhibiting the release of excitatory neurotransmitters.

Similarly to phenibut (β-phenyl-GABA), as well as pregabalin (β-isobutyl-GABA), which are close analogues of baclofen, baclofen (β-(4-chlorophenyl)-GABA) has been found to block α2δ subunit-containing voltage-gated calcium channels (VGCCs). However, it is weaker relative to phenibut in this action (Ki = 23 and 39 μM for R- and S-phenibut and 156 μM for baclofen).

Moreover, baclofen is in the range of 100-fold more potent by weight as an agonist of the GABA_B receptor in comparison to phenibut, and in accordance, is used at far lower relative dosages. As such, the actions of baclofen on α2δ subunit-containing VGCCs are likely not clinically-relevant.^[6]

The drug is rapidly absorbed after oral administration and is widely distributed throughout the body. Biotransformation is low: the drug is predominantly excreted unchanged by the kidneys.^[7]

Baclofen is often compared to phenibut, but more "messy", less euphoric, anxiolytic, and causing a stronger dizziness.

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

There are currently no anecdotal reports which describe the effects of this compound within our experience index. Additional experience reports can be found here:

• Erowid Experience Vaults: Baclofen

Baclofen has a low toxicity relative to dose.^[2] However, it is potentially lethal when mixed with depressants like alcohol, benzodiazepines or opioids.

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

Dependence and abuse potential

Baclofen is moderately physically and psychologically addictive. Discontinuation of baclofen can be associated with a withdrawal syndrome which resembles benzodiazepine withdrawal and alcohol withdrawal. Withdrawal symptoms are more likely if baclofen is used for long periods of time (more than a couple of weeks) and can occur from low or high doses.

The severity of baclofen withdrawal depends on the rate at which it is discontinued. Abrupt withdrawal is more likely to result in severe withdrawal symptoms. Acute withdrawal symptoms can be stopped by recommencing baclofen.^[8]

Tolerance will develop to the sedative-hypnotic effects within a couple of days of continuous use. After cessation, the tolerance returns to baseline in 7 - 14 days.

Withdrawal symptoms or rebound symptoms may occur after ceasing usage abruptly following a few weeks or longer of steady dosing and may necessitate a gradual dose reduction. Withdrawal symptoms may include auditory hallucinations, visual hallucinations, tactile hallucinations, delusions, confusion, delirium, disorientation, fluctuation of consciousness, insomnia, dizziness, nausea, inattention, memory impairments, perceptual disturbances, itchiness, anxiety, depersonalization, hypertonia, hyperthermia, psychosis, mania, mood disturbances, tachycardia, seizures, tremors, autonomic dysfunction, hyperpyrexia (fever), extreme muscle rigidity resembling neuroleptic malignant syndrome and rebound spasticity.^[9]

Baclofen produces cross-tolerance with all GABAgenic depressants, meaning that after its consumption, depressants will have a reduced effect.

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.

• Depressants (1,4-Butanediol, 2M2B, Alcohol, ^[10] Benzodiazepines, Barbiturates, GHB/GBL, Methaqualone, Opioids) - This combination can result in dangerous or even fatal levels of respiratory depression. These substances potentiate the muscle relaxation, sedation and amnesia caused by one another and can lead to unexpected loss of consciousness at high doses. There is also an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If this occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.
• Dissociatives - This combination can result in an increased risk of vomiting during unconsciousness and dying from the resulting suffocation. If a sudden loss of consciousness occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.
• Stimulants - It is dangerous to combine baclofen with stimulants due to the risk of excessive intoxication. Stimulants mask the sedative effect of baclofen, which is the main factor most people consider when determining their level of intoxication. Once the stimulant wears off, the effects of baclofen will be significantly increased, leading to intensified disinhibition as well as other effects. If combined, one should strictly limit themselves to only dosing a certain amount of baclofen per hour. This combination can also potentially result in severe dehydration if hydration is not monitored.

• Germany: Baclofen is a prescription medicine, according to Anlage 1 AMVV.^[11]
• Russia: Baclofen is available through a prescription.^{[citation needed]}
• Sweden: Baclofen is available through a prescription.^[12]
• Turkey: Baclofen is available at pharmacies without prescription.^{[citation needed]}
• United States: Baclofen is not a scheduled substance, but may only be sold with a prescription.^[13]

• Responsible use
• Depressant
• Gabapentinoid
• GABA
• Phenibut
• F-Phenibut
• Gabapentin
• Pregabalin

• Baclofen (Wikipedia)
• Baclofen (Erowid Vault)
• Baclofen (Isomer Design)