Flubromazolam
Viewing r1 — Apr 26, 2026 — CURRENT
Back to HistoryInteractions, related substances, and reports reflect the current entry and are not shown for historical revisions.
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]
Psychedex is in open beta. We are still fine-tuning the generation and review process. Please double-check sources.
benzodiazepines, alcohol, barbiturates +2 morebenzodiazepines, alcohol, barbiturates, z-drugs, gabapentinoids show less
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]
The name flubromazolam follows benzodiazepine naming conventions: "flu" for fluorine, "bro" for bromine, "maz" from the benzodiazepine core, and the "-olam" suffix marking the triazole ring shared with triazolam, alprazolam, and Clonazolam. No widely adopted street names exist — the compound distributed through online research chemical vendors rather than street-level markets.
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.
Key unknowns: whether flubromazolam activates specific GABA-A receptor subtypes differently (which would explain the balance between sedation, amnesia, and anxiety suppression); why blood concentration peaks so unusually slowly (~8 hours); and whether long-term use produces lasting brain changes beyond those seen with prescribed benzodiazepines.
Subjective Effects[edit]
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]
Effect Grid
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.
Sleep-transition hallucinations · Vestibular distortion · Depth perception distortion
Bodily heaviness · Dizziness · Nystagmus (eye wobbles) · Body high · Breathing alteration · Nausea · Nausea suppression
Breathing alteration · Nausea · Nausea suppression
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
Emotional lability · Anxiety · Dysphoria
Depersonalization · Derealization
Timeline
First alerts emerge as a subtle sense of relaxation and mild heaviness. The onset is gradual and easily overlooked, particularly by tolerant users.
Anxiolysis and sedation build progressively. Muscle relaxation becomes noticeable. Thought processes begin to slow.
Full sedation, pronounced amnesia, and maximum muscle relaxation. Euphoria is most prominent during the first hours of the peak. The unusually prolonged Tmax (~8 hours) means peak effects may not fully manifest until several hours into the experience.
Sedation remains substantial but intensity begins to diminish. Amnesia and motor impairment persist at clinically significant levels. Cognitive dulling continues.
Gradual return of cognitive clarity, though residual sedation, mild amnesia, and muscle relaxation linger. Motor coordination remains impaired. The long half-life (10–20 hours) means pharmacological activity continues well into this phase.
Residual drowsiness, mild cognitive fog, and subtle muscle relaxation may persist for 12–48 hours after subjective effects resolve. Psychomotor impairment can remain measurable even when the user feels baseline.
⚠ Do not drive or operate heavy machinery for at least 24 hours after last dose, and longer if any residual sedation or cognitive impairment is noticeable.
Safety[edit]
- Acute toxicity
- High
- Chronic toxicity
- High
- Withdrawal
- Life-threateningfatal risk
- Tolerance buildup
- rapid
- Tolerance reset
- 10.5 days
- Physical
- High
- Psychological
- High
- Compulsive redosing
- High
- Dose escalation
- High
- Cross-tol.
- benzodiazepines · alcohol · barbiturates
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.
Drug interactions
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
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
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.
Legal Status[edit]
Flubromazolam is controlled internationally under Schedule IV of the 1971 United Nations Convention on Psychotropic Substances[6] and has no approved therapeutic use in any jurisdiction.
| Jurisdiction | Classification | Key provisions |
|---|---|---|
| United States | Schedule I (Controlled Substances Act) | Permanent placement effective ~April 1, 2026; preceded by temporary Schedule I (December 2022, extended July 2023)[6][27] |
| United Kingdom | Class C, Schedule 1 (Misuse of Drugs Act 1971) | Amendment effective May 2017citation needed |
| Australia | Schedule 9 — Prohibited substance | Federal scheduling since approximately 2016[10] |
| Canada | Schedule IV (CDSA) | Controlled under Benzodiazepines and Other Targeted Substances Regulationscitation needed |
| Switzerland | Controlled | Scheduled since December 2015citation needed |
| Sweden | Scheduled | National scheduling circa 2015citation needed |
| United Nations | Schedule IV (1971 Convention) | CND 64th session, June 2021[6] |
Legal status varies by jurisdiction and changes over time. This table reflects available information as of the article's publication date and is not legal advice. Verify current status with local legal or regulatory authorities.
references
- [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] ^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]
- [4]
- [5]
- [6]