With my own curiosity and research been motived to find an RC similar to coke I stumbled on this one and made a order. First I tried about 16mg intranasal with no burn. About 5 minutes later felt some euphoric fuzzy feelings.
Methylnaphthidate
Encyclopedic
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 4 corroborating sources
- 2 ROAs with full dose ladders
- duration data present
- PubChem toxicity data
- classified Tentative
- classified Research-chemical
Encyclopedic
Typical encyclopedia coverage. Cross-reference for important decisions.
- 4 corroborating sources
- 2 ROAs with full dose ladders
- duration data present
- PubChem toxicity data
- classified Tentative
- classified Research-chemical
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 | 2-4 hrs |
| Insufflated | 1-5 min | 60-90 min | 1-2 hrs | 2-4 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
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 4 Erowid experience reports
Positive Effects 1
Euphoria
100.0%
70%
Adverse Effects 0
Community 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 4 reports 1 positive 2 neutral 1 cautionary visit
My brother received a sample of the piperidine drug HDMP-28 aka Methylnaphtidate from an online vendor. My past experiences with subtances include cocaine, amphetamines, MDxx, Mushrooms, LSD, LSA, DMT as well as 4-AcO-DMT and 5-MeO-DMT, various opiates/oids, kratom, salvia, nitrous oxide, DXM, syrian rue, Phenibut, Tia...
I went into this blind, no info exists on the use of this chemical online at this point. I had previous experience with ethylphenidate, and had a small amount of HDMP-28. It's legal at the moment, or at least unscheduled everywhere. I put 20 mg in a capsule, and 20mg sugar in another.
I have depression and find certain substances actually help far greater than the conventional antidepressants. For instance LSD is extraordinary for treating my depression. Once a month and I am not depressed. Mushrooms, and peyote also work quite nicely though depression returns slightly faster than with lsd.
Methylnaphthidate's nerd page
Pharmacology, chemical data, effect profiles, and more
→
Helpful Links
Report an issue or suggest an edit
Spotted incorrect or dangerous information, have a correction, a new study, or a useful addition for Methylnaphthidate? Let us know. Reports are reviewed by moderators — this is not posted publicly.