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4F-EPH

This article is a stubmissing:
Subjective Effects
Pharmacology
Tolerance
History & Culture
4F-EPH molecule structure4F-EPH molecule structure
Ethyl 2-(4-fluorophenyl)-2-(piperidin-2-yl)acetate
4-Fluoroethylphenidate, 4-FEPH, 4F-TEP
Psychoactive Class

Dosage & Duration

Dosage

Doses are population estimates that vary widely between individuals.

Threshold5 mg
Light5-10 mg
Moderate10-15 mg
Strong15-30 mg
Heavy30+ mg

Duration

Onset10-25 minutes
After Effects4-12 hours
Total5-6 hours

Subjective Effects

Subjective Effects not written up yet

Reagent Testing

Expected colorimetric results for common reagent tests. Colors show reaction change over 1–2 minutes.

Marquis(MQ)
No reaction
No reaction
Mecke(ME)
No reaction
No reaction
Mandelin(MD)
No reaction
No reaction
Robadope(RB)
No reaction
No reaction
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Pharmacology

Pharmacology not written up yet

Interactions

Dangerous

Highest risk

These combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.

AlcoholDXMDissociativesMAOIsMDMAMXENBOMe compoundsStimulantsTramadol
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Tolerance

Tolerance not written up yet

Harm Potential

Addiction & Dependence

Psychological

Moderate

Chronic 4F-EPH use is viewed as moderately addictive, with substantial abuse potential and a risk of psychological dependence for some users. Once addiction develops, stopping abruptly may bring on cravings and withdrawal symptoms.

Toxicity

Nasal/Upper Respiratory

Insufflation can cause mild to moderate damage to the nasal mucous membranes; while less caustic than ethylphenidate, repeated intranasal use without adequate recovery time will likely result in nasal cavity damage.

Cardiovascular

Vasoconstriction occurs and can become uncomfortable or hazardous as very high doses wear off, or for people who already have circulatory problems; blue or purple discoloration of extremities indicates a medical emergency.

History & Culture

History & Culture not written up yet

Legality

By Country

Illegal3
Germany flagGermanyIllegal (analog/blanket ban)
Switzerland flagSwitzerlandIllegal
United Kingdom flagUnited KingdomIllegal

References

Source Pages

  1. Bluelight: 4F-EPH Review Thread
  2. Bluelight: 4F-MPH vs 4F-EPH Discussion
  3. Drug Users Bible by Dominic Milton Trott
  4. Isomer Design (TiHKAL/PiHKAL)
  5. PsychonautWiki
  6. TripSit Factsheets
  7. Wikipedia
  8. Wikipedia: 4-Fluoroethylphenidate

Citations

  1. PubChem PUG REST: 4-Fluoroethylphenidate, erythro- (CID 176489840). pubchem.ncbi.nlm.nih.gov (n.d.). https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/176489840/property/IUPACName,MolecularFormula,MolecularWeight,CanonicalSMILES,InChIKey/JSON1
  2. Neue-psychoaktive-Stoffe-Gesetz (NpSG), Anlage 1. gesetze-im-internet.de (n.d.). https://www.gesetze-im-internet.de/npsg/anlage_1.html1
  3. Neue-psychoaktive-Stoffe-Gesetz (NpSG), § 2 Begriffsbestimmungen. gesetze-im-internet.de (n.d.). https://www.gesetze-im-internet.de/npsg/__2.html1
  4. Neue-psychoaktive-Stoffe-Gesetz (NpSG), § 3 Unerlaubter Umgang mit neuen psychoaktiven Stoffen. gesetze-im-internet.de (n.d.). https://www.gesetze-im-internet.de/npsg/__3.html1
  5. Neue-psychoaktive-Stoffe-Gesetz (NpSG), § 4 Strafvorschriften. gesetze-im-internet.de (n.d.). https://www.gesetze-im-internet.de/npsg/__4.html1
  6. Neue-psychoaktive-Stoffe-Gesetz (NpSG), current consolidated text. gesetze-im-internet.de (n.d.). https://www.gesetze-im-internet.de/npsg/BJNR261510016.html1
  7. Deutscher Bundestag Drucksache 18/8579: Entwurf eines Gesetzes zur Bekämpfung der Verbreitung neuer psychoaktiver Stoffe. dserver.bundestag.de (n.d.). https://dserver.bundestag.de/btd/18/085/1808579.pdf1
  8. Betäubungsmittelverzeichnisverordnung (BetmVV-EDI), Stand am 13. März 2026, Anhang 6, Verzeichnis e. fedlex.data.admin.ch (n.d.). https://fedlex.data.admin.ch/filestore/fedlex.data.admin.ch/eli/cc/2011/363/20260313/de/html/fedlex-data-admin-ch-eli-cc-2011-363-20260313-de-html-3.html1
  9. Änderung der Betäubungsmittelverzeichnisverordnung vom 2. Februar 2018 (AS 2018 949). fedlex.admin.ch (n.d.). https://www.fedlex.admin.ch/filestore/fedlex.data.admin.ch/eli/oc/2018/132/de/pdf-a/fedlex-data-admin-ch-eli-oc-2018-132-de-pdf-a.pdf1
  10. Verordnung über die Betäubungsmittelkontrolle (BetmKV), Stand am 23. Januar 2023. fedlex.admin.ch (n.d.). https://www.fedlex.admin.ch/filestore/fedlex.data.admin.ch/eli/cc/2011/362/20230123/de/html/fedlex-data-admin-ch-eli-cc-2011-362-20230123-de-html-3.html1

Further Reading

  1. Corkery & Schifano (2022) - First Death Involving 4F-EPH (DOI)
  2. Drugs-Forum: 4F-EPH Thread
  3. First Death Involving 4F-EPH Case Report (PMC)

Article Status

  • Josie Kins avatar
    Step 1 · Automated synthesis

    An autonomous workflow built by Josie Kins compiled this article's foundation from information published across the web.

  • Step 2 · First-pass reviewPending

    Not yet reviewed — this article is pending editorial review by Lyrea.

  • Step 3 · Citation reviewPending

    No one has reviewed this article's citations yet. That second pass checks each claim against the source it cites.

Recent changes7 human edits · latest

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24 January 2026

  1. Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more

  2. Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more

  3. Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more

  4. Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more

  5. Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more

  6. Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more

  7. Josie Kins · Updated the article · also 1,4-Butanediol, 1B-LSD, 1cP-AL-LAD and 573 more

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