I felt I had to write this report out of duty to the drugs community and cause I could not find a single decent report online about it. Now I'm all for recreational drug use and advocate the legality of weed, LSD, Shrooms, XTC etc.
Phenazepam
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 3 corroborating sources
- partial dose data
- duration data present
- 17 combo interactions documented
- classified Research-chemical
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 3 corroborating sources
- partial dose data
- duration data present
- 17 combo interactions documented
- classified Research-chemical
Aliases: Fenaz, Panda, Bonsai, Soviet benzo, Bromdihydrochlorphenylbenzodiazepine
Summary
Phenazepam is an extremely potent, long-acting benzodiazepine developed in the Soviet Union in 1975, reportedly 5-10 times stronger than diazepam. Its extremely long half-life and delayed onset of peak effects create severe risks: users often redose before feeling effects, leading to dangerous accumulation and blackouts lasting days or weeks. Not approved in most Western countries but sometimes sold online or found in counterfeit pharmaceuticals.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 0.5-1mg | 1-2mg | - | 2-4mg+ |
| Sublingual | 0.5-1mg | 1-2mg | - | 2-4mg+ |
Light
Common
Strong
Heavy
Benzo Equivalence Calculator
mg
1.0
mg
Phenazepam
=
—
mg
Diazepam
| Substance | Equivalent Dose | Potency |
|---|
⚠ 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
| ROA | Onset | Comeup | Peak | Offset | Total |
|---|---|---|---|---|---|
| Oral | 20-60 min | 1-3 hrs | 2-4 hrs | 24-72 hrs | 18 hrs |
| Sublingual | 15-45 min | 30-90 min | 2-4 hrs | 24-72 hrs | 18 hrs |
| Insufflated | 10-30 min | 30-90 min | 2-4 hrs | 24-72 hrs | 18 hrs |
Effect Profile
11 reportsScores (1–10) curated from multiple sources:
- Effect keyword matching from PsychonautWiki catalog
- Weighted by importance: core (×3), major (×2), minor (×1)
Benzodiazepine
6.6
Strong+
7/10
Strong anxiolysis and cognitive impairment with moderate euphoria, 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
cognitive impairment
amnesia
delusions of sobriety
double vision
Euphoria / Mood Lift
×1
6
physical euphoria
disinhibition
Based on reports from:
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
Acute tolerance: develops within a single session — the reset numbers above apply after sustained heavy use, not after one binge. Within-session tachyphylaxis usually resets largely overnight.
Based on general benzodiazepine patterns and user reports: noticeable tolerance can develop with repeated use over days to weeks; partial reversal over 2–4 weeks of abstinence. Individual variability is high; data are anecdotal.
Cross-Tolerances
Effects
Aggregated from 11 Erowid experience reports
Positive Effects 3
Sedation
36.4%
70%
Euphoria
36.4%
70%
Anxiety Suppression
36.4%
70%
Adverse Effects 2
Memory Suppression
36.4%
70%
Confusion
27.3%
70%
Combinations
Cross-Check Phenazepam with another substanceCommunity Trip Reports
Anecdotal first-person accounts from Reddit, Erowid, and Bluelight. Click a source to expand. Reports are harm-reduction context, not medical guidance.
Erowid 8 reports 1 positive 3 neutral 4 cautionary visit
[Erowid Note: The dose described in this report is very high, potentially beyond Erowid's 'heavy' range, and could pose serious health risks or result in unwanted, extreme effects.
So while seeking bzd for some legitimate medical purposes I talked to my doc and ended up with a decent product but which takes too long to kick in. I then resorted to self-medication and got pharma-grade Fenazepam shipped from the East. It has strong anxiolytic effects and naturally some sedative/hypnotic aspect too.
4:46 AM - Placed white crystals onto a piece of tin foil. As I began to melt them the crystals became a purple glob and did not yield much smoke. 4:52 AM - Smoking again..
[Erowid Note: Two samples of powder (even of the same chemical) with equivalent volumes won't necessarily weigh the same. For this reason, eyeballing is an inaccurate and potentially dangerous method of measuring, particularly for substances that are active in very small amounts.
Phenazepam...Seeking Disaster Let this story serve as a warning to anyone tempted by this cheap and legal benzo. It put me in the hospital and cost me my job. I am what you may call a benzo afficionado. I have tried them all, with a particular love for Etizolam (also currently legal) and Xanax.
As an avid research chemical user, I wanted to test out this phenazepam everyone was yapping about. I assumed it would be similar to benzos and produce a mild sleepy feeling, so I took it after a stimulant binge to help me sleep. Mistake #1.
Well, some of you may or may not know about this whole phenazepam craze that started cause it was marketed as 'liquid xanax' if you did a little chemistry with high proof alcohol. But it was sent as powder cause it's pure. I ordered 100mg for like $13 and was real safe with it at first.
Bluelight 6 threads 4 neutral 2 cautionary visit
He gets up early this one morning awaiting mail, browses the internet, checking this and that. *thunk* He's thinking, "was that the door latch?" It was indeed the door latch, a brown bag with a white envelope and a small plastic bag of some substance, little did he know what he was in for.
In an attempt to provide more information on this particularly interesting and legal benzodiazepine, SWIM will be assaying phenazepam for the next 3-4 weeks. The information SWIM has noted thus far (see the bottom for the initial experience): -Onset of roughly 60-90 minutes when taken orally.
As a long term drug abuser this cheap, legal, fairly easy to obtain, and relatively strong benzo (phenazepam) sounded like a dream drug. I'm not a complete idiot these days though, so I looked around at various trip reports and what the prospective downside of the drug might be.
After reading the countless countess horror stories on here about encounters with the ultra potent benzo Phenazepam, I reluctantly ordered 100mg from a fairly reliable vendor.
Background: I am heavily experienced with sedatives. My favorites are clonazepam (Klonopin), temazepam (Restoril), and phenobarbital. I'm sure secobarbital (Seconal, Tuinal) would also be added to that list if I were ever given the opportunity to try it.
Phenazepam ---- experienced with Benzos -No Mg scale, still lived fine (so far) 25-01-2011, 01:31 #1 smokeymcpot42088 Bluelighter Online Join Date: Dec 2006 Posts: 1,029 Phenazepam ---- experienced with Benzos -No Mg scale, still lived fine (so far) ----------------------------------------------------------------------...
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