Methylnaphthidate
Aliases: Hdmp-28, Methylnapthidate, methylnaphtidate
Summary
Methylnaphthidate is a research chemical with very little data on its pharmacological properties, metabolism, and toxicity. It has a limited history of human use and appeared on the research chemical market around 2014. Unlike typical methylphenidate analogs, it displays notable serotonin reuptake inhibition, giving it subjective effects more similar to cocaine or amphetamine.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 10-15mg | 15-30mg | 30-50mg | 50mg+ |
| Insufflated | 4-8mg | 8-14mg | 14-28mg | 28mg+ |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Peak | Offset | Total |
|---|---|---|---|---|
| Oral | 1-10 min | 1.5-2 hrs | 1.5-2 hrs | 3-4.2 hrs |
| Insufflated | 1-5 min | 60-90 min | 1-2 hrs | 2-3.6 hrs |
Effect Profile
4 reportsScores (1–10) curated from multiple sources:
- Effect keyword matching from PsychonautWiki catalog
- Weighted by importance: core (×3), major (×2), minor (×1)
Stimulant
5.4
Moderate+
5/10
Strong anxiety/jitters and focus with mild stimulation and euphoria
Stimulation / Energy
×3
5
stimulation
wakefulness
Euphoria / Mood Lift
×2
5
euphoria
motivation enhancement
Focus / Productivity
×2
9
focus enhancement
analysis enhancement
motivation enhancement
thought acceleration
Anxiety / Jitters
×1
10
anxiety
increased heart rate
teeth grinding
vasoconstriction
Based on reports from:
Tolerance
Build-up
develops over days to weeks of regular use
Reset
3–7 days for acute tolerance; longer for full reset
Tolerance Decay
Full tolerance
1d
Half tolerance
10d
Baseline
~18d
Effects
Aggregated from 4 Erowid experience reports
Positive Effects 1
Euphoria
100.0%
70%
Adverse Effects 0
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