My First Date With U-47700 Background: I am a physically fit, 5'11', 220lb male. I have had experience with many drugs in the past, particularly fond of opiates, but being recently subjected to random UA's as a result of pre-trial bond release, options are slim in that area.
U-47700
Well-documented
Well-documented
Multiple authoritative sources agree on dosing and effects.
- 4 corroborating sources
- 2 ROAs with full dose ladders
- duration data present
- 19 combo interactions documented
- PubChem toxicity data
- classified Research-chemical
Well-documented
Multiple authoritative sources agree on dosing and effects.
- 4 corroborating sources
- 2 ROAs with full dose ladders
- duration data present
- 19 combo interactions documented
- PubChem toxicity data
- classified Research-chemical
Aliases: U4, Pink, Pinky, Pink heroin, u47700
Summary
U-47700 is an extremely dangerous synthetic opioid with approximately 7.5 times the potency of morphine and very little history of human use. It is uniquely caustic to mucous membranes and can cause severe tissue damage with insufflated, sublingual, or smoked administration. A laboratory-grade milligram scale is absolutely essential as sub-milligram differences can mean the difference between an active dose and fatal overdose.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 5-7.5mg | 7.5-15mg | 15-25mg | 25mg+ |
| Insufflated | 4-6mg | 6-8mg | 8-10mg | 10mg+ |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset |
|---|---|---|---|---|
| Oral | 10-15 min | - | 2-3 hrs | 2-3 hrs |
| Insufflated | 5-15 min | 15-20 min | 1-2 hrs | 1-2 hrs |
| Intravenous | 0-1 min | - | 30-60 min | 30-60 min |
| Rectal | 10-15 min | - | 1-2 hrs | 1-2 hrs |
Effect Profile
9 reportsScores (1–10) curated from multiple sources:
- Effect keyword matching from PsychonautWiki catalog
- Weighted by importance: core (×3), major (×2), minor (×1)
Opioid
8.0
Intense
8/10
Strong euphoria and pain relief with mild sedation and itching/nausea
Euphoria / Warmth
×3
10
physical euphoria
cognitive euphoria
euphoria
mood lift
Analgesia
×2
8
pain relief
analgesia
Sedation / Relaxation
×1
4
sedation
dream potentiation
Itching / Nausea
×1
4
constipation
dry mouth
Based on reports from:
Tolerance
Build-up
develops within days of regular use; analgesic tolerance faster than respiratory depression tolerance
Reset
7–14 days for partial reset; full reset may take weeks — tolerance loss greatly increases overdose risk
Tolerance Decay
Full tolerance
1d
Half tolerance
21d
Baseline
~35d
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.
Effects
Aggregated from 9 Erowid experience reports
Positive Effects 3
Sedation
44.4%
70%
Euphoria
44.4%
70%
Anxiety Suppression
33.3%
70%
Adverse Effects 0
Combinations
Cross-Check U-47700 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 7 reports 6 neutral 1 cautionary visit
To start off, I've had experience with a wide variety of psychoactive substances ranging from the hardest of psychedelics like DMT, LSD, 60x Salvia to the bliss of opioids like Opium (tea), Tramadol, Oxycodone, and just about everything in-between.
I would like to share my experience since there is not much out there pertaining to U-47700. The day I ordered this substance I was not sure how much to get because I didn't know if this was going to be something I was just trying or something I was going to use on a daily basis.
As there was no real info on dosing I started very low. This is my first low dose experiment. I have no tolerance or dependance to opioids. I have used several types before (heroin, morphine, codeine, opium, Hydromorphone, Oxycodone) but non regularly.
I've written about U-4 before , but I thought I'd like to make a note about some very peculiar phenomena I've noticed after further experimentation. First, this drug shows remarkable tachyphylaxis (a special kind of rapid 'tolerance' to a drug).
Relaxing with U-47700 Yesterday, I was bored and decided to experiment with some U-47700 for the first time. It is a synthetic opiate, or at least mimics one. I poured saline solution into a 30 ml nasal spray bottle. Then, I weighed 300 mg of U-47700.
Introduction/Caution: This substance is a strong opioid and should be treated with the proper respect. It has been said it is 7.5x more potent than morphine, so a dose of as little as 25 or 30 mg could hypothetically be lethal to an opiate-sensitive person.
Bluelight 2 threads 2 neutral visit
this happend a long time ago so sice im a lazzy ass this is the first time i try to document it i cant remember the exact times of events, all i can remember is that time wasnt going normaly one hour would pass in a matter of minnets, he he, and another would go so slowwww, i hope u can understand what im wrighting sin...
man this little drug is basically like hydromorphone. Pure as hell, just dissolve in water and into the vein it goes. I've gone through 4 grams or so and yes it is horribly addicting. Brief overview of experience.
U-47700's nerd page
Pharmacology, chemical data, effect profiles, and more
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