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Flubromazolam

Overview

Flubromazolam is a synthetic depressant of the benzodiazepine class. It is the triazolo-structural analog of flubromazepam and ranks among the most potent designer benzodiazepines identified to date.[1] It amplifies the brain's primary inhibitory signal — GABA — suppressing arousal, anxiety, and muscle tension throughout the central nervous system.[2]

Flubromazolam (8-bromo-6-(2-fluorophenyl)-1-methyl-4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazepine) is a synthetic depressant of the benzodiazepine class. It is the triazolo-structural analog of flubromazepam, among the most potent designer benzodiazepines identified to date.[1] Flubromazolam is a positive allosteric modulator of GABA-A receptors, producing its effects by amplifying the brain's primary inhibitory signaling system.[2]

Entity
Flubromazolam
PSX-0195
Flubromazolam 2D chemical structure
Open Beta

Psychedex is in open beta. We are still fine-tuning the generation and review process. Please double-check sources.

NoticeAll →
•Dangerous withdrawal, taper carefully
•High overdose risk, use caution
•Compulsive use risk, monitor frequency
•High dependence, taper carefully
•Chronic toxicity, limit exposure
•1 lethal interaction(all →)
Common namesFlubromazolam
Substitutive name8-bromo-1-methyl-6-(2-fluorophenyl)-4H-S-triazolo(4,3-a)(1,4)benzodiazepine
Threshold
< 50 µg
Light
75 – 150 µg
Common
150 – 250 µg
Strong
250 – 400 µg
Heavy
400+ µg
123450 h2 h4 h6 h8 h10 h11 h
1Onset
20m–45m2Come-up
45m–1.5h3Peak
3h–5h4Plateau
2h–4h5Resolution
1.5h–3hAftereffects8h–24h
Total10h–18h
Builduprapid
Full reset10.5 days
Cross-tol.
benzodiazepines, alcohol, barbiturates +2 more
Absolute5 entries
opioid co-usealcohol co-useother CNS depressant co-usepregnancy and breastfeedingbenzodiazepine hypersensitivity
Relative2 entries
epilepsyCYP3A4 inhibitor co-administration
Dosage varies by body weight, tolerance & metabolism · Not medical advice · Terms
See an error? Suggest correction
See an error? Suggest correction

Synthesized during the 1970s–1980s pharmaceutical research wave, flubromazolam was never approved for therapeutic use.[3] It appeared on research chemical markets from 2014 and was rapidly flagged as dangerous — its active dose falls in the sub-milligram range, making precise measurement nearly impossible.[4][5] Multiple countries controlled it within years; the UN placed it in Schedule IV in 2021 and the US finalized Schedule I in April 2026.[6]

Subjective effects include deep sedation, anxiety suppression, muscle relaxation, memory blackouts, and euphoria. The experience builds slowly over hours — a heavy, all-encompassing suppression of arousal that sets it apart from shorter-acting benzodiazepines. Amnesia impairs self-assessment during the experience, producing "delusions of sobriety" that drive compulsive redosing and disinhibited behavior.[3]

Flubromazolam produces rapid physical dependence, and stopping suddenly after regular use can trigger seizures.[7] The primary danger is combination with opioids — both drugs slow breathing through overlapping pathways, and nearly all documented deaths involve this pairing.[8] Human evidence is extremely sparse: the entire published pharmacokinetic dataset comes from a single self-experiment, and no controlled toxicity studies exist.[4]

History[edit]

Discovery

Flubromazolam was synthesized during the 1970s–1980s wave of pharmaceutical research into sedative-hypnotics. It was covered under a European patent and sometimes designated JYI-73,citation needed but no clinical trials were ever conducted and no country approved it for therapeutic use.[3]

Emergence as a designer benzodiazepine

It first appeared on online research chemical markets in 2014[4] and was characterized in forensic literature by 2015.[9] Researchers flagged it alongside clonazolam as particularly dangerous — capable of producing heavy sedation and amnesia at doses so small they are nearly impossible to measure accurately.[5]

Scheduling

Switzerland and Sweden controlled it by late 2015,citation needed the UK classified it as Class C in May 2017,citation needed and Australia listed it as Schedule 9 around 2016.[10] The UN placed it in Schedule IV of the 1971 Convention in June 2021,[6] and the United States finalized permanent Schedule I placement in April 2026.[6]

Chemistry[edit]

Structural class

Flubromazolam is a triazolobenzodiazepine — a benzodiazepine with a triazole ring fused to its core,[11] sharing this structural family with alprazolam and triazolam. It is specifically the triazolo-structural analog of flubromazepam, and this ring fusion is associated with greater potency compared to standard benzodiazepines.[11]

Its molecular formula is C₁₇H₁₂BrFN₄ (molecular weight 371.2 g/mol); two halogen atoms — bromine and fluorine — embedded in the scaffold contribute to its pharmacological profile and slow its breakdown in the body.[12]

Pharmacology[edit]

Mechanism of action

Flubromazolam amplifies the brain's main inhibitory signal (GABA) by binding to GABA-A receptors and increasing chloride flow into neurons.[2][13] This produces sedation, anxiety relief, muscle relaxation, memory suppression, and anticonvulsant effects. No compound-specific binding data have been published,safety citation needed but structural analysis places it among the most potent designer benzodiazepines.[1]

In the only published human experiment, a single 0.5 mg oral dose produced sedation lasting more than 10 hours and partial amnesia exceeding 24 hours.[3][5]

Pharmacokinetics

All human pharmacokinetic data come from a single self-experiment.[4] Blood concentration peaked around 8 hours after ingestion — unusually slow for a benzodiazepine — with a half-life of 10–20 hours; the parent compound remained detectable in urine for up to 6.5 days.[4] The liver breaks it down via CYP3A4 and CYP3A5,[12] so drugs that block these enzymes — including certain antifungals, ritonavir, and grapefruit juice — would substantially increase its effects and duration.[12]

Neuroscience[edit]

Where it acts

Flubromazolam amplifies inhibitory GABA signaling throughout the brain.[2][13] The sedation comes from cortical and thalamic regions that control arousal; anxiety relief from limbic structures including the amygdala;citation needed muscle relaxation from spinal cord receptors. Memory blackouts exceeding 24 hours reflect disruption of hippocampal processes that encode new memories.[3][13]

Tolerance and neuroadaptation

With continued use, GABA-A receptors decrease in number and the brain's excitatory signaling becomes overactivated.[14][13] More drug is needed to achieve the same effect. When it stops, the overactive excitatory system produces anxiety, insomnia, and potentially life-threatening seizures.

The lethal interaction with opioids stems from GABA-A and opioid receptors sharing brainstem neurons that control breathing.[15][16] Both drugs suppress the same system simultaneously.

Subjective Effects[edit]

Summary

Flubromazolam arrives slowly. Effects take hours to build, then settle into a heavy, pervasive calm — arousal and anxiety simply stop. At common doses the experience is dominated by sedation and amnesia rather than euphoria; the world becomes muted and distance grows between thought and action.

Compared to alprazolam, flubromazolam is active at a fraction of the dose and lasts substantially longer. Relative to clonazolam — its closest designer benzodiazepine comparator — it produces similar per-milligram potency but with a more gradual onset and a more protracted course.[5]

Synthesized as a pharmaceutical candidate during the 1970s–1980s, flubromazolam was never advanced to clinical trials or approved for therapeutic use.[3] It appeared on online research chemical markets from 2014 and was rapidly flagged as a public health concern due to sub-milligram active doses that are extremely difficult to measure accurately.[4][5] The compound was placed in UN Schedule IV in 2021 and in permanent US Schedule I effective April 2026.

Subjective effects include heavy sedation, anxiolysis, muscle relaxation, amnesia, and euphoria. The experience is defined by its depth and duration — a slow-building, all-encompassing suppression of arousal and anxiety accompanied by pronounced memory blackouts that distinguish it from shorter-acting benzodiazepines.[3] Delusions of sobriety, compulsive redosing, and disinhibition are characteristic unsought effects.

Flubromazolam produces rapid physical dependence, and abrupt cessation carries seizure risk — no established equivalence dose exists for clinical withdrawal management.[6] The sub-milligram active dose range creates a narrow margin between desired and dangerous effects; synergistic respiratory depression with opioids drives nearly all documented fatalities.[7] The entire published human pharmacokinetic dataset derives from a single researcher self-experiment, and no controlled toxicity studies have been conducted.[4]

History[edit]

Discovery

Flubromazolam was synthesized during the 1970s–1980s wave of triazolobenzodiazepine development by pharmaceutical companies seeking improved sedative-hypnotics. The compound, sometimes designated JYI-73, was covered under European Patent EP 0072029 B1 (registered 1978, published 1986).citation needed It was never advanced beyond early-stage evaluation — no clinical trials were conducted, and no country approved it for therapeutic use.[3]

Emergence as a designer benzodiazepine

Designer benzodiazepines as a class began appearing on online research chemical markets around 2012.[4] Flubromazolam was first offered online from 2014[4] and was formally characterized in forensic toxicology literature by Huppertz and colleagues in 2015.[8] Moosmann, King, and Auwärter flagged it alongside clonazolam as particularly dangerous: compounds capable of producing strong sedation and amnesia at doses as low as 0.5 mg — doses "extremely difficult to measure for users handling bulk materials".[5]

Scheduling

International scheduling followed rapidly. Switzerland and Sweden controlled the compound by late 2015,citation needed the United Kingdom classified it as Class C, Schedule 1 in May 2017,citation needed and Australia listed it as Schedule 9 from approximately 2016.[9] The UN Commission on Narcotic Drugs placed flubromazolam in Schedule IV of the 1971 Convention in June 2021,[10] and the United States finalized permanent Schedule I placement effective April 2026.[10]

Chemistry[edit]

Structural class

Flubromazolam is a triazolobenzodiazepine — a benzodiazepine in which a 1,2,4-triazole ring is fused to the diazepine ring, incorporating a methyl group at the triazole nitrogen. This modification, shared with triazolam and alprazolam, is associated with increased potency relative to non-fused benzodiazepines.[11] Flubromazolam is specifically the triazolo-structural analog of flubromazepam, formed by fusion of the methyl-triazole ring onto the parent scaffold.

The compound carries a bromine at the 8-position and a 2-fluorophenyl group at the 6-position. These halogen substitutions distinguish it from triazolam (which carries chlorine at both positions) and contribute to its pharmacological profile.[11]

Molecular properties

Molecular formulaC₁₇H₁₂BrFN₄
Molecular weight371.2 g/mol

The molecular scaffold consists of a seven-membered diazepine ring fused to a benzene ring, with the additional triazole creating a tricyclic system. The bromine and fluorine substituents are both electron-withdrawing halogens that influence receptor binding and metabolic stability.

Stereochemistry

Flubromazolam contains no chirality centres and exists as a single structural form. No stereoisomeric considerations apply.

Physical properties

No published data on melting point, solubility, or crystal form exist. High lipophilicity is implied by the compound's high plasma protein binding and large volume of distribution.[12] The halogenated aromatic system is consistent with low water solubility and high membrane permeability, typical of the triazolobenzodiazepine class.

Pharmacology[edit]

Mechanism of action

Flubromazolam acts as a positive allosteric modulator of GABA-A receptors. It binds to the interface between α and γ subunits of the GABA-A complex, amplifying the effect of the brain's main inhibitory neurotransmitter (GABA) by increasing chloride ion flow into neurons.[2][13] This mechanism — boosting existing inhibitory signals rather than directly activating the receptor — produces sedation, anxiety relief, muscle relaxation, memory suppression, and anticonvulsant effects.

No binding affinity data specific to flubromazolam have been published.safety citation needed Its exceptional potency — pharmacological effects at oral doses of 0.5 mg[3] — is inferred from its triazolobenzodiazepine structure and from modelling that predicts this subclass as the most potent among designer benzodiazepines.[1]

A single 0.5 mg oral dose produced sedation lasting more than 10 hours and partial amnesia exceeding 24 hours in the only published human experiment.[3][5]

Pharmacokinetics

The only published human pharmacokinetic data come from a single self-experiment in which a researcher ingested 0.5 mg orally.[4] Peak blood concentration was reached at approximately 8 hours — unusually slow for a benzodiazepine — with a terminal half-life estimated at 10–20 hours. The parent compound was detectable in urine for up to 6.5 days and the primary metabolite for up to 8 days.[4]

The liver enzymes CYP3A4 and CYP3A5 are the primary metabolic pathway, producing hydroxylated metabolites that are further processed into glucuronide conjugates.[12] Predicted liver clearance is low, consistent with the long half-life.[12] Metabolites confirmed in both laboratory and human studies serve as the primary forensic detection targets.[8][4]

All human pharmacokinetic values derive from a single subject. Individual variation in liver enzyme activity, body composition, and co-administered substances could substantially alter these parameters. Potent CYP3A4 inhibitors (certain antifungals, ritonavir, clarithromycin, grapefruit juice) would be expected to increase flubromazolam exposure and prolong its effects.[12]

Neuroscience[edit]

Where it acts

Flubromazolam amplifies inhibitory GABA signaling across the central nervous system.[2][13] Its sedative and amnestic effects are primarily driven by GABA-A receptors in cortical and thalamic regions that govern arousal and memory. Anxiety relief involves receptors concentrated in limbic structures including the amygdala and hippocampus, while muscle relaxation engages spinal cord receptors.citation needed

The pronounced memory blackouts — partial amnesia exceeding 24 hours at 0.5 mg[3] — reflect disruption of hippocampal processes required to encode new memories into long-term storage.[13]

Tolerance and neuroadaptation

Chronic use triggers the brain's compensatory response: GABA-A receptors are downregulated and internalized, while excitatory glutamate signaling (via NMDA and AMPA receptors) becomes sensitized.[14][13] This rebalancing is the molecular basis of tolerance — more drug is needed for the same effect.

When the drug is removed, the now-disinhibited excitatory system produces a hyperexcitable state: anxiety, insomnia, and potentially life-threatening seizures. The lethal synergy with opioids reflects the co-location of GABA-A and μ-opioid receptors on brainstem neurons that control breathing.[15][16]

Subjective Effects[edit]

Summary

Flubromazolam produces a slow-building wave of sedation and anxiety dissolution that deepens over hours rather than minutes, reflecting its unusually long time to peak effect. At low doses the experience is dominated by calm and mild euphoria; at common doses, heavy sedation and pronounced memory blackouts take over — users frequently cannot accurately assess their own level of impairment, a phenomenon described as "delusions of sobriety" that drives compulsive redosing.[3] Set and setting modulate the anxiolytic and euphoric components, but the sedative and amnestic effects are relatively context-independent at common doses.

Compared to alprazolam, flubromazolam is active at roughly one-quarter to one-half the dose with a substantially longer duration of both subjective effects and residual impairment. Relative to clonazolam — its closest comparator among designer benzodiazepines — it appears to produce comparable per-milligram potency but with a more gradual onset and more protracted course.[5]

Effect Grid

Dose Level:
Description

At common doses (150–250 µg oral), the characteristic flubromazolam profile fully manifests: pronounced sedation, significant anxiolysis, and clear muscle relaxation. Euphoria is frequently reported at this range. Emotional responses are blunted and social inhibitions markedly reduced. Disinhibition and increased talkativeness may occur.

Physically, motor impairment becomes substantial — coordination is visibly affected and gait may become unsteady. Slurred speech is possible. Drowsiness is prominent and many users will fall asleep during the experience.

Anterograde amnesia becomes a significant feature at this range — users may have incomplete or absent recall of events during the experience. Thought deceleration and disorganisation are pronounced. The risk of compulsive redosing is elevated due to delusions of sobriety. Total duration typically spans 10–14 hours with residual impairment persisting well beyond subjective effects.

Modeled from the effect's dose-dependence curve — not per-substance measurements.

Perception(8)likelihood · intensity
Dreaming suppression
likely
Proprioceptive distortion
possible
Spatial disorientation
possible
Visual acuity suppression
possible
Sleep-transition hallucinations
possible
Vestibular distortion
possible
Depth perception distortion
possible
Double vision!
possible

Sleep-transition hallucinations · Vestibular distortion · Depth perception distortion

Body(12)likelihood · intensity
Sedation
likely
Motor control impairment!
likely
Muscle relaxation
likely
Physical fatigue
likely
Bodily heaviness
likely
Dizziness
possible
Nystagmus (eye wobbles)
possible
Body high
possible
Respiratory depression!
rare

Bodily heaviness · Dizziness · Nystagmus (eye wobbles) · Body high · Breathing alteration · Nausea · Nausea suppression

Breathing alteration · Nausea · Nausea suppression

Thinking(20)likelihood · intensity
Cognitive impairment
likely
Decision impairment!
likely
Thought deceleration
likely
Analysis suppression
likely
Cognitive fatigue
likely
Focus suppression
likely
Information processing suppression
likely
Delusions of sobriety!
possible
Suggestibility enhancement!
possible

Cognitive fatigue · Focus suppression · Information processing suppression · Memory suppression · Thought disorganization · Creativity suppression · Language suppression · Memory fragmentation · Motivation suppression · Suggestibility enhancement · Confusion · Compulsive redosing urge · Cognitive euphoria · Amnesia · Delirium

Memory suppression · Thought disorganization · Creativity suppression · Language suppression · Memory fragmentation · Motivation suppression · Confusion · Compulsive redosing urge · Cognitive euphoria · Amnesia · Delirium

Feeling(8)likelihood · intensity
Anxiety suppression
likely
Emotional suppression
likely
Euphoria
possible
Irritability
possible
Emotional lability
possible
Anxiety
rare
Depression!
rare
Dysphoria
rare

Emotional lability · Anxiety · Dysphoria

Self(7)likelihood · intensity
Disinhibition
likely
Communication suppression
possible
Craving
possible
Sociability enhancement
possible
Depersonalization
rare
Derealization
rare
Self-control suppression!
rare

Depersonalization · Derealization

Time(2)likelihood · intensity
Temporal disorientation
possible
Time alteration
possible
Awareness(1)likelihood · intensity
Reality testing impairment!
rare
report missing effect
Likelihood: how common this effect is at the selected dose level.This effect has safety implications — review before use.

Timeline

Safety[edit]

Harm
Acute toxicity
High
Chronic toxicity
High
Withdrawal
Life-threateningfatal risk
Tolerance buildup
rapid
Tolerance reset
10.5 days
Dependence
Physical
High
Psychological
High
Compulsive redosing
High
Dose escalation
High
Cross-tol.
benzodiazepines · alcohol · barbiturates
Risk Shape
TOXPHYPSYWDRREDTOL

Toxicity

Acute toxicity

No lethal dose data have been published for flubromazolam in any species.safety citation needed Used alone, its intrinsic toxicity appears low — typical of the benzodiazepine class, which has a wider safety margin than older sedatives like barbiturates. The first published poisoning case involved prolonged unconsciousness, dangerously low blood pressure, and muscle breakdown requiring hospital admission.[17]

Three factors make it acutely dangerous despite that class-level margin: its sub-milligram active dose makes accurate dosing nearly impossible in unregulated preparations;[5] amnesia and delusions of sobriety drive compulsive redosing;[3] and combination with opioids drives nearly all documented deaths.

Fatality data

No published case establishes flubromazolam as the sole cause of death — all fatal cases involved co-administered central nervous system depressants. In Victoria, Australia (2018–2022), it appeared in 12 of 133 designer benzodiazepine-associated deaths.[18] In North Carolina (2020–2022), it was found in counterfeit prescription pills linked to multiple deaths.[19]

Broader surveillance shows 92.7% of US illicit benzodiazepine-involved deaths involved opioids,[8] and flubromazolam ranked among the top three designer benzodiazepines in adverse events and deaths reported to UNODC.[20] Impaired driving cases with flubromazolam as the sole intoxicant confirm significant psychomotor impairment from the drug alone.[3][21]

Drug supply contamination

Flubromazolam has been detected as an adulterant in unregulated opioid supplies[22] and in counterfeit prescription pills.[19] The WHO specifically noted its "potential to increase unintentional opioid overdoses".[3] Standard fentanyl test strips do not detect benzodiazepines, and no widely validated point-of-care test for flubromazolam exists.[22]

Psychological risks

The main psychological risk is anterograde amnesia — memory blackouts lasting more than 24 hours documented at a single low dose.[3] Combined with delusions of sobriety — the inability to recognize one's own impairment — this reliably produces additional dosing without memory of prior ingestion.[3]

Disinhibition and loss of behavioral control are consistently reported[11][23] and documented in impaired driving cases.[21] The combination of amnesia, disinhibition, and high potency has led to flubromazolam's identification as a drug-facilitated sexual assault risk.[24] Severe withdrawal brings anxiety, panic attacks, dissociation, and perceptual distortions.[3]

Tolerance & dependence

Tolerance to flubromazolam's sedative effects develops within days of continuous use.[11] The WHO noted this rapid tolerance onset "suggests that taking increased doses and developing physical dependence is likely".[3] The mechanism: GABA-A receptors decrease in number and the brain's excitatory signaling becomes sensitized.[14][13]

When the drug stops, this imbalance produces withdrawal: muscle aches, insomnia, severe anxiety, panic, dissociation, vomiting, and seizures.[3] No established equivalence dose exists for converting to a longer-acting benzodiazepine for tapering — withdrawal must be symptom-guided and individually titrated by a clinician.[7] Cross-tolerance with all benzodiazepines, Z-drugs, alcohol, and barbiturates is expected.

1LETHAL
21DANGEROUS
26CAUTION
12UNGRADED
60 rules0 SOURCE-VERIFIED1 EDITOR-REVIEWED

The primary lethal interaction is with opioids. Both drugs suppress breathing through overlapping brainstem pathways,[15][16] and 92.7% of illicit benzodiazepine-involved deaths in US surveillance involved opioids.[8] Naloxone does not reverse benzodiazepine respiratory depression; flubromazolam appears as an adulterant in unregulated opioid supplies;[22] and its half-life may outlast naloxone.

Alcohol and other CNS depressants produce additive-to-synergistic depression.[18] In English and Welsh coronial cases, flubromazolam co-occurred with at least one other designer benzodiazepine in 48% of deaths.[25] CYP3A4 inhibitors (itraconazole, ketoconazole, ritonavir, clarithromycin, grapefruit juice) substantially increase flubromazolam levels by slowing its metabolism.[12] Kratom (Mitragyna speciosa) complicates withdrawal management via liver enzyme inhibition.[7]

Contraindications

7 known
5ABSOLUTE
2RELATIVE

Opioid co-use is an absolute contraindication due to synergistic respiratory depression.[13]

Alcohol and other central nervous system depressants carry absolute contraindication status given documented synergistic lethality.

CYP3A4 inhibitor co-administration is a relative contraindication — potent inhibitors substantially increase flubromazolam exposure.[12]

Pregnancy and breastfeeding: No data exist for flubromazolam specifically. Class-level benzodiazepine concerns include neonatal withdrawal syndrome.[13]

Seizure disorders: Benzodiazepines are anticonvulsant during use, but abrupt withdrawal can trigger seizures.[7] Individuals with seizure disorders face compounded risk.

Known benzodiazepine hypersensitivity is an absolute contraindication.

Harm Reduction[edit]

Forms & Identification

Reagent ResultsNot recorded+ add reagent results
AppearanceNot recorded+ add appearance
Red FlagsNot recorded+ add red flags

Flubromazolam's active dose is measured in fractions of a milligram — small enough that minor variations in preparation cause dramatically different outcomes. Volumetric dosing from a verified solution is the only reliable method. Weighing raw powder at this scale requires laboratory-grade equipment most people don't have access to.

Counterfeit pharmaceutical tablets containing flubromazolam have been documented in place of prescription benzodiazepines and opioids. Standard fentanyl test strips do not detect benzodiazepines. Drug checking services using mass spectrometry or benzodiazepine immunoassay strips offer the most reliable identification.

Guidelines

  • Test all substances with a drug checking service when possible — benzodiazepine immunoassay strips provide a baseline check but cannot confirm specific compounds.
  • Use volumetric dosing from a calibrated solution. Do not attempt to measure sub-milligram quantities by eye or with consumer-grade scales.
  • Pre-measure a single dose and secure or remove the remaining supply before ingesting. Amnesia and delusions of sobriety reliably lead to unintended redosing.
  • Write down the time of ingestion and dose on paper and place it somewhere visible — this information may be critical if memory loss occurs.
  • Do not drive or operate machinery. Impairment may persist well beyond 24 hours and is not reliably self-assessed.
  • Do not use alone. A sober companion should be briefed on what to watch for and when to call for help.
  • Allow at least 48 hours for full recovery before any activity requiring coordination, judgment, or memory.

Set & Setting

The slow onset — peak effects may not arrive for 6–8 hours — is a primary cause of dangerous overdose. Redosing before the full effect arrives amplifies exposure far beyond the intended level.

A familiar, safe environment with a sober companion present is strongly advised. The amnesia and delusions of sobriety mean that a trusted person capable of preventing redosing is more important here than with most other benzodiazepines.

Aftercare & integration. Memory gaps are expected and may span hours to days. Reviewing notes, messages, and speaking with anyone present during the experience can help reconstruct the timeline. Residual sedation, cognitive fog, and impaired coordination may persist for 24–48 hours after the last dose.

Prioritize sleep, hydration, and light nutrition during recovery. Avoid driving, important decisions, or additional substance use until full cognitive clarity has returned. If memory blackouts, disinhibited behavior, or unplanned redosing occurred, honest self-assessment of the experience is important for future risk decisions.

Recovery & Support

Flubromazolam dependence requires medical supervision to manage safely — abrupt cessation can cause seizures. No established equivalence dose exists for converting to a longer-acting benzodiazepine for tapering, so withdrawal management is symptom-guided and must be individually titrated by a clinician experienced in benzodiazepine withdrawal.

Peer support communities and addiction medicine specialists can provide critical help. The Benzodiazepine Information Coalition (benzoinfo.com) offers resources specifically for benzodiazepine dependence and withdrawal. SAMHSA's National Helpline (1-800-662-4357) provides free referrals in the United States.

Recovery resources, crisis lines, and support pathways → View all

Emergency Response

Recognizing an emergency:

  • Breathing becomes very slow, shallow, or stops
  • Blue or grey lips and fingertips
  • Unresponsive to loud voice or sternal rub
  • Seizure activity (especially during withdrawal)
  • Prolonged unconsciousness beyond expected sedation

Immediate steps:

  • 1. Call emergency services immediately if breathing is impaired or the person is unresponsive.
  • 2. Place the person in the recovery position (on their side) to protect the airway.
  • 3. Do not induce vomiting.
  • 4. Stay with the person and monitor breathing until help arrives.

What to tell the dispatcher:

  • The substance taken (flubromazolam, a designer benzodiazepine), estimated dose and time.
  • Current symptoms — breathing rate, consciousness level, skin color.
  • Whether any other substances were taken.
  • Good Samaritan laws in many jurisdictions protect people who call for help during an overdose.

Reversal agents:

  • Naloxone does not reverse benzodiazepine effects but should be administered if opioid co-exposure is suspected.
  • Flumazenil can reverse benzodiazepine sedation but carries serious risks including seizures, especially in dependent users — it is not recommended for routine use.[26]
  • Flubromazolam's long half-life (10–20 hours) may outlast reversal agents, requiring extended monitoring.

Safety[edit]

Harm
Acute toxicity
High
Chronic toxicity
High
Withdrawal
Life-threateningfatal risk
Tolerance buildup
rapid
Tolerance reset
10.5 days
Dependence
Physical
High
Psychological
High
Compulsive redosing
High
Dose escalation
High
Cross-tol.
benzodiazepines · alcohol · barbiturates
Risk Shape
TOXPHYPSYWDRREDTOL

Toxicity

Acute toxicity

No lethal dose data have been published for flubromazolam in any species.safety citation needed When used alone, the compound's intrinsic toxicity appears low — consistent with the benzodiazepine class generally, which has a wider safety margin than older sedatives like barbiturates. The first published case report described a severe single-drug poisoning with prolonged unconsciousness, dangerously low blood pressure, and muscle breakdown requiring hospital admission.[17]

Three factors converge to make flubromazolam acutely dangerous despite its class-level safety margin: (1) the sub-milligram active dose range makes accurate dosing extremely difficult in unregulated preparations,[5] (2) amnesia and delusions of sobriety drive compulsive redosing,[3] and (3) synergistic respiratory depression with opioids drives nearly all documented deaths.

Fatality data

No published case establishes flubromazolam as the sole cause of death — all fatal cases have involved co-administered central nervous system depressants. In Victoria, Australia (2018–2022), it was detected in 12 of 133 designer benzodiazepine-associated deaths, always alongside other drugs.[18] In North Carolina (2020–2022), it appeared in counterfeit prescription pills linked to multiple deaths.[19]

Broader surveillance confirms the pattern: US illicit benzodiazepine-involved deaths increased 519.6% from 2019 to mid-2020, with 92.7% involving opioids.[7] Flubromazolam ranked among the top three designer benzodiazepines in adverse events and deaths reported to UNODC.[20] Impaired driving cases where flubromazolam was the sole identified intoxicant confirm substantial psychomotor impairment from the drug alone.[3][21]

Drug supply contamination

Flubromazolam has been detected as an adulterant in unregulated opioid supplies[22] and in counterfeit prescription pills.[19] The WHO specifically noted its "potential to increase unintentional opioid overdoses".[3] Standard fentanyl test strips do not detect benzodiazepines, and no widely validated point-of-care test for flubromazolam exists.[22]

Psychological risks

The dominant psychological risk is anterograde amnesia — memory blackouts lasting more than 24 hours are documented at a single 0.5 mg dose.[3] Combined with delusions of sobriety, this creates a high risk of compulsive redosing — users may take additional doses without memory of prior ingestion.[3]

Disinhibition and loss of behavioral control are consistently reported[11][23] and documented in impaired driving cases.[21] The combination of amnesia, disinhibition, and high potency has led to flubromazolam's identification among designer benzodiazepines with drug-facilitated sexual assault risk.[24]

Severe withdrawal-related psychological symptoms — including anxiety, panic attacks, dissociative symptoms, and perceptual distortions — are reported following cessation of regular use.[3]

Tolerance & dependence

Tolerance to flubromazolam's sedative effects develops rapidly — within days of continuous use.[11] The WHO documented online reports of rapid tolerance onset, noting this pattern "suggests that taking increased doses and developing physical dependence is likely".[3]

The underlying mechanism involves downregulation of GABA-A receptors and compensatory sensitization of excitatory glutamate signaling.[14][13] When the drug is stopped, this imbalance produces withdrawal symptoms including muscle aches, sleep disturbances, severe anxiety, panic attacks, dissociative symptoms, cramping, vomiting, and seizures.[3]

No established long-acting benzodiazepine equivalence dose exists for flubromazolam, making clinical withdrawal management particularly difficult — symptom-based treatment is required.[6] Cross-tolerance with all benzodiazepines, Z-drugs, alcohol, and barbiturates is expected from the shared GABA-A mechanism.

1LETHAL
21DANGEROUS
26CAUTION
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60 rules0 SOURCE-VERIFIED1 EDITOR-REVIEWED

The primary lethal interaction is with opioids. Synergistic respiratory depression occurs because opioid and GABA-A receptors are co-located on brainstem neurons that control breathing.[15][16] US surveillance shows 92.7% of illicit benzodiazepine-involved deaths involved opioids.[7]

Three factors make this interaction especially hazardous: naloxone does not reverse benzodiazepine-mediated respiratory depression; flubromazolam has been found as an adulterant in unregulated opioid supplies;[22] and the drug's long half-life (10–20 hours) may exceed naloxone's duration of action.

Alcohol produces additive-to-synergistic central nervous system and respiratory depression, documented in polydrug fatality series.[18]

Other central nervous system depressants — including other benzodiazepines, Z-drugs, gabapentinoids, muscle relaxants, antipsychotics, and sedating antihistamines — produce additive or synergistic depression. In English and Welsh coronial cases, flubromazolam co-occurred with at least one other designer benzodiazepine in 48% of cases.[25]

CYP3A4 inhibitors (itraconazole, ketoconazole, ritonavir, clarithromycin, grapefruit juice) are expected to substantially increase flubromazolam blood levels based on CYP3A4/5 as the primary metabolic pathway.[12]

Kratom (Mitragyna speciosa) was noted as a complicating factor in benzodiazepine withdrawal management via liver enzyme inhibition.[6]

Contraindications

7 known
5ABSOLUTE
2RELATIVE

Opioid co-use is an absolute contraindication due to synergistic respiratory depression.[13]

Alcohol and other central nervous system depressants carry absolute contraindication status given documented synergistic lethality.

CYP3A4 inhibitor co-administration is a relative contraindication, as potent inhibitors would be expected to substantially increase flubromazolam exposure.[12]

Pregnancy and breastfeeding: No data exist for flubromazolam specifically. Class-level benzodiazepine concerns include neonatal withdrawal syndrome.[13]

Seizure disorders: While benzodiazepines are anticonvulsant during use, abrupt withdrawal can trigger seizures.[6] Individuals with seizure disorders face compounded risk.

Known benzodiazepine hypersensitivity is an absolute contraindication.

Harm Reduction[edit]

Forms & Identification

Reagent ResultsNot recorded+ add reagent results
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Red FlagsNot recorded+ add red flags

Flubromazolam's sub-milligram active dose range means that even small variations in preparation can produce dramatically different effects. Volumetric dosing from a verified solution is the only reliable method — weighing raw powder at this scale requires laboratory-grade equipment beyond what most users possess. Any dose handled as loose powder or broken from a pressed tablet should be treated as imprecise.

Counterfeit pharmaceutical tablets containing flubromazolam have been documented in place of prescription benzodiazepines and opioids. Standard fentanyl test strips do not detect benzodiazepines. Drug checking services that use mass spectrometry or immunoassay-based benzodiazepine strips offer the most reliable identification.

Guidelines

  • Test all substances with a drug checking service when possible — point-of-care benzodiazepine immunoassay strips offer a baseline check but cannot confirm specific compounds.
  • Use volumetric dosing from a calibrated solution. Do not attempt to measure sub-milligram quantities by eye or with consumer-grade scales.
  • Pre-measure a single dose and secure or remove remaining supply before ingesting. Amnesia and delusions of sobriety reliably lead to unintended redosing.
  • Write down the time of ingestion and dose on paper and place it somewhere visible — this information may be critical if memory loss occurs.
  • Do not drive or operate machinery. Impairment may persist well beyond 24 hours and is not reliably self-assessed.
  • Do not use alone. A sober companion should be briefed on what to watch for and when to call for help.
  • Allow at least 48 hours for full recovery before any activity requiring coordination, judgment, or memory.

Set & Setting

The slow onset (peak effects may not arrive for 6–8 hours) makes patience essential — redosing before the full effects manifest is a leading cause of dangerous overdose with this compound. A familiar, safe environment with a sober companion present is strongly advised. The pronounced amnesia and delusions of sobriety mean that a trusted person who can prevent redosing is more important with this substance than with most other benzodiazepines.

Aftercare & integration. Memory gaps are expected and may span hours to days. Reviewing notes, messages, and speaking with anyone present during the experience can help reconstruct the timeline. Residual sedation, cognitive fog, and impaired coordination may persist for 24–48 hours after the last dose.

Prioritize sleep, hydration, and light nutrition during recovery. Avoid driving, important decisions, or additional substance use until full cognitive clarity has returned. If memory blackouts, disinhibited behavior, or unplanned redosing occurred, honest self-assessment of the experience is important for future risk decisions.

Recovery & Support

Flubromazolam dependence requires medical supervision to manage safely — abrupt cessation can cause seizures. No established equivalence dose exists for converting flubromazolam to a longer-acting benzodiazepine for taper, so withdrawal management is symptom-guided and must be individually titrated by a clinician experienced in benzodiazepine withdrawal.

Peer support communities and addiction medicine specialists can provide critical help. The Benzodiazepine Information Coalition (benzoinfo.com) offers resources specifically for benzodiazepine dependence and withdrawal. SAMHSA's National Helpline (1-800-662-4357) provides free referrals in the United States.

Recovery resources, crisis lines, and support pathways → View all

Emergency Response

Recognizing an emergency:

Immediate steps:

  • 1. Call emergency services immediately if breathing is impaired or the person is unresponsive.
  • 2. Place the person in the recovery position (on their side) to protect the airway.
  • 3. Do not induce vomiting.
  • 4. Stay with the person and monitor breathing until help arrives.

What to tell the dispatcher:

  • The substance taken (flubromazolam, a designer benzodiazepine), estimated dose and time.
  • Current symptoms — breathing rate, consciousness level, skin color.
  • Whether any other substances were taken.
  • Good Samaritan laws in many jurisdictions protect people who call for help during an overdose.

Reversal agents:

  • Naloxone does not reverse benzodiazepine effects but should be administered if opioid co-exposure is suspected.
  • Flumazenil can reverse benzodiazepine sedation but carries serious risks including seizures, especially in dependent users — it is not recommended for routine use.[26]
  • Flubromazolam's long half-life (10–20 hours) may outlast reversal agents, requiring extended monitoring.

Frequently asked questions

What is Flubromazolam?

Flubromazolam is a triazolobenzodiazepine and GABA-A positive allosteric modulator active at sub-milligram oral doses, never approved for therapeutic use. It emerged on research-chemical markets from 2014 and was placed in UN Schedule IV in 2021 and US Schedule I in 2026.

How long does Flubromazolam last?

Total duration by route of administration — Oral: 10 – 18 hours. Ranges vary with dose and individual factors; see the duration table for onset, peak, and after-effect phases.

Where can I find dosage information for Flubromazolam?

Psychedex publishes a dosage table for Flubromazolam on this page covering these routes of administration: oral. Dose values are presented only in that table, always alongside their route of administration.

What are dangerous combinations with Flubromazolam?

The highest-severity documented interactions for Flubromazolam: Opioids (Lethal), Alpha-2 adrenergic receptor antagonist (Dangerous), Antipsychotics (Dangerous), Atypical antipsychotics (Dangerous), Benzodiazepines (Dangerous). See the interactions section for the full list with mechanisms and severity levels.

Is Flubromazolam addictive?

Psychedex records tolerance and dependence data rather than a yes/no rating. Recorded tolerance indicators for Flubromazolam: tolerance builds rapid; full reset takes 10.5 days; cross-tolerance develops with benzodiazepines, alcohol, barbiturates, z-drugs, gabapentinoids. See the article's dependence and safety sections for recorded dependence data.

experience reports

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First-person accounts of subjective effects, timing, and outcomes — submitted for harm reduction.

references

  1. [1] 
    ^abWaters LJ, Manchester KR, Maskell P, Haegeman C, Haider S (2017) The use of a quantitative structure-activity relationship (QSAR) model to predict GABA-A receptor binding of newly emerging benzodiazepines — Science & Justice doi:10.1016/j.scijus.2017.12.004
  2. [2] 
    ^abcZhu S, Sridhar A, Teng J, Howard RJ, Lindahl E, Hibbs RE (2022) Structural and dynamic mechanisms of GABAA receptor modulators with opposing activities — Nature Communications doi:10.1038/s41467-022-32212-4
  3. [3] 
    ^abcdefghijklmWHO Expert Committee on Drug Dependence (43rd ECDD) (2020) Critical Review Report: FLUBROMAZOLAM Link
  4. [4] 
    ^abcdeHuppertz LM, Moosmann B, Auwärter V (2018) Flubromazolam - Basic pharmacokinetic evaluation of a highly potent designer benzodiazepine — Drug Testing and Analysis doi:10.1002/dta.2203
  5. [5] 
    ^abcdeMoosmann B, King LA, Auwärter V (2015) Designer benzodiazepines: A new challenge — World Psychiatry doi:10.1002/wps.20236
  6. [6] 
    ^abcdefDEA (2026) Federal Register: Schedules of Controlled Substances: Placement of Clonazolam, Diclazepam, Etizolam, Flualprazolam, and Flubromazolam in Schedule I of the Controlled Substances Act Link

references

  1. [1] 
    ^abWaters LJ, Manchester KR, Maskell P, Haegeman C, Haider S (2017) The use of a quantitative structure-activity relationship (QSAR) model to predict GABA-A receptor binding of newly emerging benzodiazepines — Science & Justice doi:10.1016/j.scijus.2017.12.004
  2. [2] 
    ^abcZhu S, Sridhar A, Teng J, Howard RJ, Lindahl E, Hibbs RE (2022) Structural and dynamic mechanisms of GABAA receptor modulators with opposing activities — Nature Communications doi:10.1038/s41467-022-32212-4
  3. [3] 
    ^abcdefghijklmnoWHO Expert Committee on Drug Dependence (43rd ECDD) (2020) Critical Review Report: FLUBROMAZOLAM Link
  4. [4] 
    ^abcdefgHuppertz LM, Moosmann B, Auwärter V (2018) Flubromazolam - Basic pharmacokinetic evaluation of a highly potent designer benzodiazepine — Drug Testing and Analysis doi:10.1002/dta.2203
  5. [5] 
    ^abcdefMoosmann B, King LA, Auwärter V (2015) Designer benzodiazepines: A new challenge — World Psychiatry doi:10.1002/wps.20236
  6. [6] 
    ^abcdButler M, Pirkle J, Carmichael A, Carlson-Dexter P, Rosella T (2025) Successful symptom-based management of active withdrawal from multiple illicit benzodiazepines — BMJ Case Reports doi:10.1136/bcr-2025-266077
Last updated Jun 4, 2026