Halazepam - Substance Search

Summary TheDrug.Wiki TripSit

Halazepam is a trifluoromethyl derivative of nordazepam (desmethyldiazepam) with anxiolytic, anticonvulsant, sedative, and muscle relaxant properties. It is metabolized into pharmacologically active desmethyldiazepam with a half-life of 30-100 hours, contributing to prolonged effects and accumulation with repeated use. Halazepam was marketed as having lower toxicity and less tendency to cause paradoxical hostility than diazepam, though it was withdrawn from the US market in 2009 due to poor sales.

Dose Information TheDrug.Wiki TripSit

ROA	Light	Common	Strong	Heavy
Oral	10-20mg	20-40mg	40-80mg	80mg+

Light Common Strong Heavy

Benzo Equivalence Calculator

Convert from

mg

Convert to

20.0 mg Halazepam

=

— mg Diazepam

⚠ These are approximate equivalences for educational and cross-tapering reference. Individual response, tolerance, and half-life differences mean actual equivalence varies. Always consult a healthcare provider for tapering guidance.

Onset, Duration & After-effects TheDrug.Wiki TripSit

ROA	Onset	Comeup	Peak	Offset	After Effects	Total
Oral	30-60 min	1-2 hrs	1-3 hrs	6-12 hrs	24-48 hrs	8.5-18 hrs

Effect Profile

Scores (1–10) curated from multiple sources:

Effect keyword matching from PsychonautWiki catalog
Weighted by importance: core (×3), major (×2), minor (×1)

Full methodology

Benzodiazepine 7.1

Strong+ 7/10

Strong anxiolysis, cognitive impairment, and euphoria with mild sedation

Anxiolysis ×3

10

anxiety suppression anxiolytic muscle relaxation muscle relaxant emotion suppression

Sedation / Relaxation ×2

5

sedation muscle relaxation

⚠ Motor / Cognitive Impairment ×1

10

motor control loss memory suppression amnesia delusions of sobriety double vision

Euphoria / Mood Lift ×1

10

cognitive euphoria physical euphoria disinhibition

Based on reports from:

Erowid Experience Reports PsychonautWiki Halazepam

Tolerance

Build-up develops over 1–4 weeks of daily use; hypnotic tolerance faster than anxiolytic tolerance

Reset weeks to months depending on half-life and duration of use; taper recommended

Tolerance Decay

Full tolerance 14d Half tolerance 14d Baseline ~60d

Sedative and anticonvulsant effects exhibit rapid tolerance with repeated dosing over days to weeks, similar to other benzodiazepines. Cross-tolerance is substantial across benzodiazepines and extends partially to other GABAergic sedatives (alcohol, barbiturates, Z-drugs). Tolerance generally recedes gradually over weeks to months of abstinence; individual variability is large. Data quality is limited; values are heuristic to support harm reduction, not precise pharmacometrics.