Bromazepam

# Research Output: Bromazepam

## Chemical Identity

**Verified from PubChem CID 2441 [Ref 1]:**
- **Molecular formula:** C₁₄H₁₀BrN₃O  
- **Molecular weight:** 316.15 g/mol  
- **IUPAC name:** 7-bromo-5-pyridin-2-yl-1,3-dihydro-1,4-benzodiazepin-2-one  
- **InChIKey:** VMIYHDSEFNYJSL-UHFFFAOYSA-N  
- **CAS number:** 1812-30-2 (confirmed in PMID 11799841 [Ref 10] and PMID 41 [Ref 41])  
- **PubChem CID:** 2441  
- **DEA code number:** 2748 (confirmed from DEA Orange Book via web search [Ref 41])  
- **Roche development code:** Ro 5-3350 (confirmed in PMID 237849 [Ref 37])  

**SMILES (derived from structure; not returned by PubChem API — FLAG for editorial verification):**  
O=C1CN=C(c2ccccn2)c2cc(Br)ccc2N1

**InChI (web-retrieved [Ref 41]):**  
InChI=1S/C14H10BrN3O/c15-9-4-5-11-10(7-9)14(17-8-13(19)18-11)12-3-1-2-6-16-12/h1-7H,8H2,(H,18,19)

**Discrepancies with seed data:**  
The brief's seed data correctly lists the systematic name and chemical class. The PubChem CID (2441), molecular formula, and MW were absent from the brief but have now been confirmed. The SMILES and IUPAC fields were blank in the brief — both are now populated above.

**Stereochemistry:** No chiral centers; bromazepam does not exist as stereoisomers (confirmed from structure). No active isomers to specify.

**Physical properties (web-retrieved, unverifiable without primary source):** Melting point reported as ~237–238°C in chemical supplier data. Solubility in water is low (lipophilic compound, logP ≈ 2.8). Stability: standard benzodiazepine stability; light and temperature sensitive.

---

## Pharmacology

### Mechanism of Action
Bromazepam is a positive allosteric modulator (PAM) of the γ-aminobutyric acid type-A (GABA-A) receptor, acting at the classical benzodiazepine recognition site located at the interface of α and γ subunits (Braestrup & Squires 1978 [Ref 20]). Binding potentiates the frequency of chloride-channel opening in response to GABA without directly activating the channel. This mechanism was confirmed for bromazepam using flumazenil (a competitive BZD-site antagonist) as a reversal agent: flumazenil fully blocked bromazepam's anxiolytic-like phenotype in animal models (Vieira et al. 2022 [Ref 2]).

The anxiolytic action of bromazepam is attenuated in prodynorphin-knockout mice with altered GABA-A γ2 and β2 subunit expression, indicating opioid-GABAergic cross-talk modulates efficacy (Femení et al. 2011 [Ref 3]).

Bromazepam enhanced spinal presynaptic inhibition via GABA-mediated dorsal root reflex potentiation in cat preparations; this effect required intact GABA levels and was abolished by GABA-depleting agents (Suzuki 1984 [Ref 5]).

Compared to etifoxine (a non-BZD GABA-A modulator), bromazepam at 0.5–1 mg/kg i.p. produced neurological and locomotor impairments, quantifying its sedative vs. anxiolytic balance (Mattei et al. 2019 [Ref 4]).

### Receptor Binding Affinity
**FLAG — No bromazepam-specific Ki or EC50 values for GABA-A receptor subtypes were found in published primary literature via PubMed or OpenAlex searches.** Bromazepam is confirmed to bind the classical benzodiazepine recognition site (α/γ interface) and is sensitive to flumazenil reversal. Subunit-selectivity profile analogous to classic BZDs (likely α1-, α2-, α3-, α5-containing receptors) but no published selectivity studies specific to bromazepam were identified.

### Pharmacokinetics (Human)

**Absorption:**
- **Bioavailability:** ~84% oral (web-retrieved, from Wikidoc [Ref 41]; unverified against primary source — FLAG)
- **Tmax:** Approximately 2.3 hours fasting; prolonged to ~2.8 hours with food; food significantly reduces Cmax from 259 to 169 ng/mL and reduces AUC (Fujii et al. 1990 [Ref 7])
- Equivalent bioavailability between liquid (oral solution) and solid (capsule/tablet) formulations confirmed (Ascalone et al. 1984 [Ref 8])
- Nasogastric tube administration yields comparable pharmacokinetics to oral dosing (Podilsky et al. 2009 [Ref 6])

**Distribution:**
- **Volume of distribution:** 1.44 L/kg in young adults (mean age 21–29 years); reduced to 0.88 L/kg in elderly (60–81 years) (Ochs et al. 1987 [Ref 35])
- **Protein binding:** ~71% in young adults (28.8% free fraction); decreases to ~65% protein-bound in elderly (34.8% free fraction) (Ochs et al. 1987 [Ref 35])

**Elimination:**
- **Half-life:** 20–30 hours in young healthy adults (Ochs et al. 1987 [Ref 35]): baseline values of ~23 hours, extending to 29 hours with cimetidine co-administration and ~28 hours with propranolol
- **NOTE — Half-life discrepancy:** Web sources (Wikidoc [Ref 41], product prescribing information [Ref 42]) report 10–20 hours. The 20–30h range is from the only identified controlled human PK study (Ochs et al. 1987 [Ref 35], N=32 healthy volunteers). The 10–20h range appears in secondary sources without traceable primary citation. The generation agent should flag this and prefer the published primary study value, noting the discrepancy.
- **Oral clearance:** 0.76 mL/min/kg in young adults; reduced to 0.41 mL/min/kg in elderly — nearly 50% reduction (Ochs et al. 1987 [Ref 35])

**Metabolism:**
- Hepatic microsomal oxidation (Ochs et al. 1987 [Ref 35])
- Active metabolite: 3-hydroxybromazepam (hydroxylated at position 3), which retains pharmacological activity and has a half-life approximately equal to the parent compound (web-retrieved [Ref 41, 42])
- CYP enzyme involvement: fluvoxamine-mediated inhibition of bromazepam metabolism operates via CYP1A2, CYP3A4, and CYP2C19 (Sproule et al. 1997 [Ref 40]; van Harten 1995 [Ref 13]); the specific CYP isoform(s) primarily responsible for bromazepam oxidation have not been definitively assigned in controlled human studies — **FLAG for editorial clarification**
- Metabolite review: Mandrioli et al. 2010 [Ref 12] covers BZD metabolism updates including bromazepam analytical methods

**Excretion:** Primarily renal (web-retrieved [Ref 41])

**Special Populations:**
- **Elderly:** Significantly higher Cmax (132 vs. 82 ng/mL), smaller Vd, lower clearance (~50% reduction), and higher free fraction; dose reduction is recommended (Ochs et al. 1987 [Ref 35]; Greenblatt et al. 1991 [Ref 34])
- **Gender:** No significant influence on bromazepam PK (Ochs et al. 1987 [Ref 35])
- **Oral contraceptives:** No significant effect on bromazepam PK (Ochs et al. 1987 [Ref 35])
- **Hepatic disease:** Expected to impair clearance (hepatic microsomal pathway); no specific bromazepam hepatic impairment study found — **FLAG**

**Diazepam equivalency:** 3 mg bromazepam ≈ 5 mg diazepam (Wikidoc [Ref 41]); confirmed contextually by clinical trial dosing (bromazepam 18 mg/day vs. diazepam 15 mg/day used as comparators in Fontaine et al. 1983 [Ref 39])

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## History

Bromazepam was synthesized by F. Hoffmann-La Roche Ltd., as part of the systematic benzodiazepine medicinal chemistry program initiated after Leo Sternbach's discovery of chlordiazepoxide at Roche in 1955 (Wick 2013 [Ref 36]). Diazepam (Valium) followed in 1963. Bromazepam carried the development code **Ro 5-3350** (documented in the first published clinical comparison, Sonne & Holm 1975 [Ref 37]), indicating its position in Roche's systematic numbering of the 5,000+ compounds derived from the 1,4-benzodiazepine scaffold.

**Patented:** Reported as 1961 or 1963 in secondary web sources — the precise patent date could not be confirmed via available primary APIs. Roche authorship is confirmed by the "Ro" code designation.

**First clinical approval and marketing:** Bromazepam was approved for medical use reportedly in 1974 (web-retrieved). The first double-blind controlled clinical trials were published in 1975 (Sonne & Holm 1975 [Ref 37]; Cassano et al. 1975 [Ref 38]).

**Brand names:** Lexotan (Roche, Australia, UK historical, Brazil, Italy); Lexotanil (continental Europe); Lexomil (France); Lectopam (Canada); Lexaurin (Czech Republic, Slovakia); Lexilium; Normoc (historical); Brazepam; Calmepam; Somalium; Durazanil; Rekotnil; Brozam; Zepam [Ref 41].

**Regulatory history:**
- Approved and marketed in multiple European countries, Australia, Latin America, and parts of Asia
- Not FDA-approved in the United States (no marketing authorization); classified as DEA Schedule IV (CSN 2748) but not clinically available
- Withdrawn in UK and Canada as prescription drug (remains classified but no active marketing authorization)
- Placed on WHO Convention on Psychotropic Substances Schedule IV

---

## Subjective Effects

*Note: Controlled human subjective-effects studies specific to bromazepam were not identified. The following is derived from published controlled clinical trials comparing bromazepam to placebo or active comparators.*

**Anxiolytic effects:** Multiple double-blind RCTs document reduction in Hamilton Anxiety Rating Scale scores compared to placebo from the first week of treatment (Fontaine et al. 1983 [Ref 39]; Kragh-Sørensen et al. 1990 [Ref 44]). Effect on somatic anxiety factor of the Hamilton scale is particularly prominent (Fontaine et al. 1983 [Ref 39]).

**Sedation/somnolence:** Tiredness, sedation, and hypersomnia were the most consistently reported adverse effects compared to placebo in multicenter RCT data (Kragh-Sørensen et al. 1990 [Ref 44]; Cloxazolam vs bromazepam: Ansseau & von Frenckell [Ref 26]). Bromazepam produced dose-dependent neurological and locomotor impairment in preclinical comparisons (Mattei et al. 2019 [Ref 4]).

**Disinhibition:** An early clinical comparison noted that bromazepam "is likely to exert a disinhibiting or 'activating' action, unlike most other benzodiazepines in clinical use" (Cassano et al. 1975 [Ref 38]).

**Muscle relaxation:** Demonstrated in fibromyalgia (Quijada-Carrera et al. 1996 [Ref 25]) and preoperative anxiolysis contexts (Erb et al. 1998 [Ref 24]); enhanced spinal cord presynaptic inhibition confirmed in animal models (Suzuki 1984 [Ref 5]).

**Memory impairment:** No bromazepam-specific controlled amnesia studies identified; class-level evidence for anterograde amnesia is well-established for benzodiazepines (Edinoff et al. 2021 [Ref 19]).

**Duration data (seed data from brief):**
- Onset: 14–15 minutes oral
- Come-up: 15–120 minutes
- Peak: 2–12 hours
- Offset: 30–60 minutes
- Aftereffects: 12–22 hours
- Total: 6–15 hours

*These duration data are consistent with an intermediate-to-long-acting benzodiazepine (half-life 20–30h) but no controlled human timeline study specific to bromazepam's subjective onset/offset was identified in the literature. The long aftereffects and total duration are plausible given PK data. FLAG for editorial review.*

---

## Safety & Toxicity

### Overdose and Case Reports
- **Protracted deep coma** was reported following bromazepam poisoning alone, with the authors noting that "bromazepam intoxication is very common but surprisingly rarely reported" in the literature (Lakhal et al. 2010 [Ref 27]).
- **Fatal combined overdose (pharmacobezoar case):** Bromazepam was identified at 2,500 mcg/L in femoral blood alongside tramadol (34,000 mcg/L), propranolol (6,000 mcg/L), zopiclone (1,200 mcg/L), and citalopram (700 mcg/L) in a fatal multidrug case (Drevin et al. 2024 [Ref 28]).
- **Fatal combined overdose (planned complex suicide):** Bromazepam 2.06 mg/L at toxic concentration combined with citalopram, hydroxyzine, cocaine, and lidocaine (Pélissier-Alicot et al. 2021 [Ref 29]).
- **Methcathinone + bromazepam coma:** Bromazepam 8.89 mg/L in serum (highly elevated) combined with methcathinone and alcohol produced coma; remarkably, respiratory function was maintained despite this very high concentration in the presence of a CNS stimulant (Belhadj-Tahar & Sadeg 2005 [Ref 30]).
- **Drug interaction fatality:** Bromazepam was within therapeutic range in a case where fluvoxamine + levomepromazine caused fatal CYP2D6-mediated drug interaction (Takei et al. 2024 [Ref 31]).
- **Chemsex-context death:** Bromazepam found alongside 4-MPD, cocaine, sildenafil, and nevirapine in fatal intoxication (Cartiser et al. 2021 [PMID 33370656]; *this PMID was found in search results but not individually fetched — note as web_retrieved level*).

### Acute Toxicity
- **Toxic blood concentration threshold:** Case data indicate levels >2 mg/L (2000 mcg/L) are associated with severe toxicity or fatality in polydrug contexts [Ref 28, 29]. 
- **LD50:** Not identified for humans. Bromazepam-palladium complex LD50 was 780 ± 80 mg/kg (mouse, i.p.) (Vieira et al. 2022 [Ref 2]); specific bromazepam LD50 in humans is unknown — FLAG.
- The low acute lethality of benzodiazepines alone is a class feature; fatalities almost invariably involve polydrug combinations, especially with alcohol, opioids, or other CNS depressants (class-level evidence, Edinoff et al. 2021 [Ref 19]).

### Chronic / Long-term Risks
- **Dementia risk:** New use of benzodiazepines was associated with a 60% increased risk of dementia in a 15-year prospective population-based study (HR 1.60, 95% CI 1.08–2.38; Billioti de Gage et al. 2012 [Ref 17]).
- **Cognitive impairment:** Long-term benzodiazepine users show persistent cognitive deficits after withdrawal; meta-analysis showed significant impairment in most cognitive domains still present at ≥6 months post-cessation (Barker 2003 [Ref 18]).
- **Respiratory depression:** BZDs potentiate opioid-induced respiratory depression in a dose-dependent, additive-to-synergistic manner (class-level evidence from animal models; Xu et al. 2020 [PMID 32021808]).

### Organ Toxicity
No bromazepam-specific organ toxicity studies (hepatotoxicity, nephrotoxicity) were identified. As a hepatically metabolized drug, impaired liver function is expected to reduce clearance and increase exposure — **FLAG for no primary data available**.

### Contraindications (from product information [Ref 42])
- Hypersensitivity to benzodiazepines
- Severe respiratory depression
- Sleep apnea syndrome
- Myasthenia gravis
- First trimester of pregnancy (relative)

---

## Harm Reduction

### Polydrug Risk
The most significant acute harm from bromazepam is combination with CNS depressants. All fatal and near-fatal case reports in the literature involved polydrug use, predominantly: alcohol, opioids (tramadol, opioid analgesics), antidepressants (citalopram, fluvoxamine), antipsychotics (levomepromazine), and stimulants (cocaine, 4-MPD) [Ref 27–31]. Alcohol co-ingestion is particularly dangerous: benzodiazepines and ethanol both act on GABA-A receptors, producing synergistic CNS and respiratory depression.

### Flumazenil Reversal
Flumazenil (Romazicon), a competitive GABA-A benzodiazepine-site antagonist, reverses bromazepam's anxiolytic and sedative effects (Vieira et al. 2022 [Ref 2]). It is used in clinical settings for BZD overdose reversal; however, caution is required in patients with BZD dependence (risk of precipitating acute withdrawal and seizures) and its short half-life (~1 hour) means repeat dosing may be needed given bromazepam's long half-life of 20–30 hours.

### Testing
Bromazepam is detected on standard benzodiazepine immunoassays and confirmed by GC-MS or LC-MS/MS. The m/z transition 316→182 is used for bioanalytical quantification (Gonçalves et al. 2005 [Ref 11]).

### Diazepam Equivalency for Harm Reduction
For harm reduction purposes: 3 mg bromazepam ≈ 5 mg diazepam [Ref 41]. This is relevant for dose comparison, tolerance estimation, and withdrawal management planning.

---

## Tolerance & Dependence

### Tolerance Mechanism
Repeated benzodiazepine use produces tolerance via: (1) downregulation/uncoupling of GABA-A receptor subunits, particularly the α1 and γ2 subunits; (2) compensatory upregulation and sensitization of excitatory glutamatergic (NMDA) systems (Navarrete et al. 2026 [Ref 46]). Cross-tolerance with other benzodiazepines and alcohol is established at the class level.

Bromazepam-specific: prodynorphin knockout mice showed attenuated anxiolytic response to bromazepam with altered GABA-A β2/γ2 subunit expression, suggesting opioid system modulation of GABAergic tolerance mechanisms (Femení et al. 2011 [Ref 3]).

### Cross-tolerance
Class-level cross-tolerance exists between benzodiazepines and between benzodiazepines and alcohol (class evidence, Edinoff et al. 2021 [Ref 19]). No bromazepam-specific cross-tolerance studies were found.

### Dependence Liability and Withdrawal
Physical dependence and a clinically significant withdrawal syndrome have been documented for the benzodiazepine class. Bromazepam was specifically used as the reference compound for benzodiazepine withdrawal management in a 168-patient double-blind trial: 65.5% of patients in the bromazepam 3–6 mg/day group were successfully withdrawn over 6 months (Lemoine et al. 2006 [Ref 22]).

Abrupt cessation of benzodiazepines can produce: rebound anxiety, insomnia, tremor, sweating, irritability, and in severe cases, tonic-clonic seizures, nonconvulsive status epilepticus, and delirium tremens. Clinical management requires gradual tapering, typically with substitution to a long-acting benzodiazepine (Navarrete et al. 2026 [Ref 46]).

Cognitive deficits from long-term use persist after withdrawal — meta-analysis confirms significant impairment in most cognitive domains at ≥6 months post-cessation with incomplete recovery (Barker 2003 [Ref 18]).

**Tolerance onset rate (bromazepam-specific):** No published data on specific timeline for bromazepam tolerance development were found. Class-level evidence suggests tolerance to sedative effects develops within 1–2 weeks, while tolerance to anxiolytic effects is slower. This is not confirmed for bromazepam specifically — **FLAG**.

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## Interactions

### Pharmacokinetic Interactions (Affecting Bromazepam Levels)

| Interacting Drug | Mechanism | Effect on Bromazepam | Source |
|---|---|---|---|
| Fluvoxamine | CYP1A2, CYP3A4, CYP2C19 inhibition | Increased plasma levels | Ref 13, 40 |
| Cimetidine (1.2 g/day) | Hepatic microsomal inhibition | Clearance ↓50%; t½ 23→29h | Ref 35 |
| Propranolol (160 mg/day) | Hepatic blood flow reduction | t½ 23→28h | Ref 35 |
| Oral contraceptive steroids | No significant interaction | No clinically relevant PK change | Ref 35 |
| Phenobarbital | CYP enzyme induction (anticipated) | Potential clearance increase | Class inference — FLAG |

### Pharmacodynamic Interactions (Additive CNS Depression)
- **Alcohol:** Additive GABA-A potentiation; synergistic sedation and respiratory depression; documented in fatal overdose cases [Ref 30]
- **Opioids:** Additive/synergistic respiratory depression; FDA boxed warning class applies (class evidence [PMID 32021808])
- **Other CNS depressants** (antipsychotics, antidepressants, other BZDs): Additive CNS depression
- **Tramadol:** Abolishes tramadol-induced seizures but enhances respiratory depression (class evidence [PMID 27641627])

### Note on Fluvoxamine Interaction Specificity
The fluvoxamine–bromazepam interaction is specifically documented in pharmacokinetic review literature: fluvoxamine inhibits CYP3A4, CYP2C19, and CYP1A2, all of which are implicated in bromazepam's hepatic oxidation (Sproule et al. 1997 [Ref 40]; Perucca et al. 1994 [Ref 14]). This is considered a clinically significant drug–drug interaction requiring dose monitoring.

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## Legal Status

| Jurisdiction | Status | Schedule/Class | Notes |
|---|---|---|---|
| **International** | Controlled | Convention on Psychotropic Substances Schedule IV | Since approximately 1980s |
| **United States** | DEA Schedule IV (CSN 2748) | Not FDA-approved; no clinical availability | Prescription use not authorized |
| **United Kingdom** | Class C, Schedule 4 Part 1 | Misuse of Drugs Act 1971 / Misuse of Drugs Regulations 2001 | Confirmed GOV.UK controlled drugs list [Ref 43] |
| **Australia** | Schedule 4 (Prescription Only) | Standard for Uniform Scheduling of Medicines and Poisons | Lexotan 3mg and 6mg TGA-registered (ARTG 52269, 52270) [Ref 47]; PBS listed [Ref 48] |
| **Canada** | Schedule IV (CDSA) | Controlled Drugs and Substances Act | Marketed as Lectopam |
| **Germany, France, Italy, Switzerland, Belgium** | Prescription | Varies by country; general BZD prescription requirements | Widely available as branded generics |
| **Brazil** | Prescription (Lista C1) | Controlled via ANVISA | Marketed as Lexotan |

**US Note:** Bromazepam is DEA Schedule IV but has not received FDA approval for clinical marketing. It is therefore unavailable as a licensed prescription medicine in the US market, though it may be encountered as a diverted or unscheduled import.

---

## Clinical Trials

**ClinicalTrials.gov search** for "bromazepam" returned no trials with bromazepam as the specific primary intervention (4 results returned on broader anxiety queries; none specifically studying bromazepam as primary drug). 

**Historical published trials (not ClinicalTrials.gov registered — pre-registration era):**
- Sonne & Holm 1975 [Ref 37]: N=30, crossover, 15 mg/day, anxiety neurosis
- Cassano et al. 1975 [Ref 38]: N=58, parallel group, vs. diazepam, psychoneurotic inpatients
- Fontaine et al. 1983 [Ref 39]: N=48, placebo-controlled, 18 mg/day, generalized anxiety disorder
- Kragh-Sørensen et al. 1990 [Ref 44]: N=245, multicenter, 3 mg twice daily, GAD general practice
- Quijada-Carrera et al. 1996 [Ref 25]: N=164, placebo-controlled, 3 mg/day, fibromyalgia
- Lemoine et al. 2006 [Ref 22]: N=168, vs. cyamemazine, BZD withdrawal management
- Ansseau & von Frenckell ~1991 [Ref 26]: N=837 total, parallel group, 12 mg/day reference, vs. cloxazolam

No active or recently registered ClinicalTrials.gov studies were identified for bromazepam as primary intervention (as of May 2026).

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## Community Feedback Analysis

No community feedback was submitted in Part A2 of the brief. Standard research directives applied.

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## Gaps & Flags

### Safety-Critical Flags
1. **🚩 SMILES string not API-verified:** The SMILES for bromazepam (O=C1CN=C(c2ccccn2)c2cc(Br)ccc2N1) was derived from the confirmed molecular structure; the PubChem API used in this pipeline returns InChIKey and formula but not SMILES directly. Editorial confirmation against the PubChem compound page is recommended.

2. **🚩 Half-life discrepancy:** The published controlled human PK study (Ochs et al. 1987 [Ref 35]) reports half-life **20–30 hours**. Secondary sources (Wikidoc [Ref 41], prescribing information [Ref 42]) report **10–20 hours**. The seed data duration range (total 6–15h, aftereffects 12–22h) appears to be internally inconsistent with a 20–30h half-life, which would predict longer lingering effects. The generation agent should use the primary published study value (20–30h) and flag the discrepancy prominently.

3. **🚩 Bioavailability not verified from primary source:** The 84% figure appears in Wikidoc and the Lexotan prescribing information but no original controlled human bioavailability study was identified in PubMed. Some studies (Fujii et al. 1990 [Ref 7]; Ascalone et al. 1984 [Ref 8]) confirm food-effect and formulation comparisons but not absolute bioavailability vs. IV reference.

4. **🚩 CYP isoform assignment incomplete:** Fluvoxamine inhibits bromazepam metabolism via CYP1A2, CYP3A4, and CYP2C19 (indirect evidence from SSRI interaction studies [Ref 13, 40]). The *primary* CYP isoform responsible for the main oxidative metabolic pathway has not been definitively assigned in published primary studies for bromazepam. This is flagged as a gap.

5. **🚩 No specific Ki/EC50 binding data found:** No published binding affinity measurements (Ki at GABA-A subtypes, IC50 at BZD site) for bromazepam were identified in PubMed or OpenAlex searches. All mechanistic data is class-level or inferred from functional (behavioral) studies. The seed data's claim of "GABA-A receptor positive allosteric modulator" is pharmacologically accurate and confirmed at functional level.

6. **🚩 No LD50 in humans:** Lethal dose in humans is unknown. Bromazepam-palladium complex LD50 was 780 ± 80 mg/kg in mice (i.p.; [Ref 2]). Toxic blood concentrations from forensic cases suggest levels >2 mg/L are dangerous in polydrug contexts [Ref 28, 29]. Case data also suggest that even 8.89 mg/L may not be immediately fatal when CNS stimulants are co-administered [Ref 30] — highlighting the complexity of overdose toxicology.

7. **🚩 Tolerance timeline not established:** No published human study specifically measuring tolerance development rate for bromazepam was found. Class inference applies.

8. **🚩 Hepatic impairment pharmacokinetics:** No controlled bromazepam PK study in hepatic impairment was identified; class-level inference predicts impaired clearance.

9. **🚩 Seed dose data — clinical cross-check:** The seed dose data (common 3–6 mg oral) aligns well with published clinical trials using 3 mg/day (Kragh-Sørensen [Ref 44]) to 18 mg/day (Fontaine [Ref 39]) ranges. The "heavy" dose of 12+ mg aligns with the clinical maximum of 24 mg/day for hospitalized patients [Ref 41]. No discrepancy requiring correction identified; however, the dose data appears verified and plausible.

10. **🚩 Duration data — not verified from primary source:** No controlled human study measuring onset time, peak duration, or offset duration was identified. The seed data durations (onset 14–15 min, peak 2–12h, total 6–15h) are plausible for the formulation and PK profile but represent community consensus / class-inference rather than published controlled data.

11. **🚩 Social anxiety specific trial PMID not found:** Versiani et al. conducted a controlled trial of bromazepam in social anxiety disorder (referenced in Versiani 2000 [Ref 23] as one of two BZD controlled studies in SAD), but the specific PMID of the original social phobia trial was not identified via PubMed searches. The 2000 review article [Ref 23] is the best available citation for this claim.

### Data Not Found
- No published animal LD50 for bromazepam itself (only for bromazepam-palladium complex)
- No human bioavailability studies with IV comparator
- No studies on bromazepam in pregnancy/lactation (beyond class-level contraindications)
- No forensic detection window data for urine testing specific to bromazepam
- No studies on bromazepam use in renal impairment
- No direct receptor binding affinity (Ki) data for bromazepam at GABA-A subtypes