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
- 29 combo interactions documented
- toxicity data (PsychonautWiki)
- 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
- 29 combo interactions documented
- toxicity data (PsychonautWiki)
- 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
Sources
Insufflated
Dose ladder — dose.wiki, PsychonautWikiOnset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset | Total |
|---|---|---|---|---|---|
| Oral | 10-15 min | - | 2-3 hrs | 2-3 hrs | 4.17-6.25 hrs |
| Insufflated | 5-15 min | 15-20 min | 1-2 hrs | 1-2 hrs | 2.33-4.58 hrs |
| Intravenous | 0-1 min | - | 30-60 min | 30-60 min | 1-2.02 hrs |
| Rectal | 10-15 min | - | 1-2 hrs | 1-2 hrs | 2.17-4.25 hrs |
Effect Profile
7 reportsScores (0–10) 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
Falls quickly once you stop, at a rate you can't judge. After any break, treat your tolerance as gone.
No tolerance chart. Our decay curves for opioids were estimates, and a curve can make tolerance look longer-lasting than it is, which is the dangerous direction.
Opioid tolerance drops fast when you stop, and even a few days off can be enough, so a dose that used to be normal can now stop your breathing. Overdose deaths rise sharply after prison, detox or leaving treatment, and tolerance also falls during a hospital stay. After any break, start with a much smaller amount, try a test dose first, don't use alone, and keep naloxone within reach. Alcohol, benzodiazepines, gabapentinoids and other sedatives make an opioid overdose much more likely.
Sources: FRANK: heroin · National Harm Reduction Coalition · WHO: opioid overdose · Merrall et al. 2010 · Binswanger et al. 2007 · Strang et al. 2003 · FDA 2019: gabapentinoids and breathing
Effects
Aggregated from 7 single-substance Erowid experience reports; 2 Erowid reports where another drug was taken too are left out
Each bar shows the share of analyzed reports whose text mentions that effect — a mention is not always a first-hand experience (fear of an effect or something witnessed can count). Mentions saying the effect did not happen are left out; that check reads keywords, so it can miss some. The shaded band on a bar, and the small range after its number, is the 95% interval: where the share could plausibly be with other reports of the same kind. Fewer reports, wider band. Tap or hover any number for details. The second value is the Bluelight extractor's per-effect confidence; a dash means the row is Erowid-derived, which has no confidence measurement.
Too few reports for bars: these effects come from 7 single-substance Erowid reports, and a bar is drawn only from 20 reports or more. With fewer, a percentage cannot tell a common effect from a rare one. Counts are shown instead. Why 20?
Effect glossary — · full glossary
Positive Effects 1
3 of 7
–
Adverse Effects 0
Combinations
Cross-Check U-47700 with another substanceCommunity Trip Reports
Anecdotal first-person accounts from Reddit, Erowid, Bluelight, and Dose.wiki. Click a source to expand. Reports are harm-reduction context, not medical guidance. Tags summarise each author's own verdict — how reports are classified.
Erowid 7 reports 1 positive 5 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 1 thread 1 cautionary visit
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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Helpful Links
Add missing routes to PsychonautWiki Journal
The PsychonautWiki Journal app already has U-47700, but its built-in entry only covers Insufflated. Here are the other routes we have data for. You can't edit a built-in substance, but you can add a Custom Unit for any of these routes to log it.
⬇ Download import file
Import this file as custom substances
and you get "U-47700 (Substance Search)" with every
route's full dose ladder and timeline, no typing. Works on iOS and
Android (v15+); the format is confirmed by the app's
developer. The manual values below work for older
versions.
Custom Unit doses
- Oralcommon ~ 11.25 mg
Dose & duration (reference)
U-47700: routes the PsychonautWiki Journal app is missing Source: SubstanceSearch (substancesearch.com) Oral dose (mg): light 5-7.5 · common 7.5-15 · strong 15-25 · heavy 25+ Oral duration: onset 10-15m · peak 2-3h · offset 2-3h · total 4.17-6.25h · after-effects 2-4h Intravenous duration: onset 0-1m · peak 0.5-1h · offset 0.5-1h · total 1-2.02h · after-effects 1-3h Rectal duration: onset 10-15m · peak 1-2h · offset 1-2h · total 2.17-4.25h · after-effects 2-4h Note: ranges are harm-reduction guidance, not a prescription. Start low, go slow, and test your substances.
Custom Units carry a single dose per route, so the full ranges live in the reference above. A route's suggested dose is the midpoint of its common range. Ranges are harm-reduction guidance, not a prescription.
Report an issue or suggest an edit
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