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    🧪 This is a research chemical with limited data on its long-term health effects, toxicity profile, and safe dosage ranges.

    Isophenidine Encyclopedic
    Encyclopedic
    Typical encyclopedia coverage. Cross-reference for important decisions.
    • 1 source
    • 2 ROAs with full dose ladders
    • duration data present
    • classified Research-chemical

    Aliases: NPDPA, Isopropylphenidine, N-isopropyl-1,2-diphenylethylamine, NSC 34569

    Dissociative Research-chemical

    Summary Drugs.Wiki

    Isophenidine (NPDPA) is a dissociative research chemical of the 1,2-diarylethylamine (phenidine) family, acting as an NMDA-receptor antagonist with possible weak dopaminergic/noradrenergic reuptake inhibition. Human data are extremely sparse — most dose, timing and effect information comes from a handful of anecdotal self-reports rather than clinical studies. Identity confusion is a notable risk: it has been mis-sold as or confused with isopropylphenidate. Treat dose figures as approximate and start low.

    Dose Information Drugs.Wiki

    ROA Light Common Strong Heavy
    Oral 75-125mg 125-200mg 200-250mg 250mg+
    Insufflated 60-100mg 100-150mg 150-200mg 200mg+
    Light Common Strong Heavy
    Sources

    Oral

    Dose ladder — Drugs.Wiki

    Insufflated

    Dose ladder — Drugs.Wiki

    Onset, Duration & After-effects Drugs.Wiki

    ROA Onset Peak Offset Total
    Oral 30-60 min 1-3 hrs 2-3 hrs 3-6 hrs
    Insufflated 5-15 min 15-60 min 0.5-2 hrs 1-3 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

    Dissociative 4.4
    Moderate 4/10

    Mild dissociative depth with low mania and motor impairment

    Dissociative Depth ×3
    5
    derealization depersonalization
    ⚠ Mania / Compulsion ×1
    2
    euphoria
    Insight / Novel Thought ×2
    0
    ⚠ Motor / Sensory Impairment ×1
    2
    numbness
    View methodology →

    Tolerance

    Effects Drugs.Wiki

    Positive
    Negative
    Neutral
    Positive
    Negative
    Neutral
    Positive
    Neutral
    Isophenidine's nerd page Pharmacology, chemical data, effect profiles, and more
    →

    Helpful Links

    📘 Experience Reports 📖 Drugs.Wiki 📖 PsychonautWiki
    Add to PsychonautWiki Journal

    The PsychonautWiki Journal logging app doesn't include every substance. To track Isophenidine there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:

    ⬇ Download import file Import this file as custom substances and you get "Isophenidine (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.
    Name
    Isophenidine
    Unit
    mg
    Description 
    Isophenidine
Source: SubstanceSearch (substancesearch.com)

Oral dose (mg): threshold 75 · light 75-125 · common 125-200 · strong 200-250 · heavy 250+
Insufflated dose (mg): threshold 40-60 · light 60-100 · common 100-150 · strong 150-200 · heavy 200+

Oral duration: onset 0.5-1h · peak 1-3h · offset 2-3h · total 3-6h
Insufflated duration: onset 5-15m · peak 0.25-1h · offset 0.5-2h · total 1-3h

Note: ranges are harm-reduction guidance, not a prescription. Start low, go slow, and test your substances.

    Tip: for quicker logging you can also add a Custom Unit in the app, e.g. common dose ~ 162.5 mg (Oral).

    The app keeps custom substances simple, so the full dose ranges live in the description text above. Ranges are harm-reduction guidance, not a prescription.