Isomethadone
Summary
Once a pharmaceutical drug also known as isoamidone, this opioid analgesic and methadone analogue was withdrawn from the market and is seldom seen today. Rarely abused, though reports state it is around twice as potent as methadone, and more euphoric.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 1.5-2.5mg | 2.5-7.5mg | 7.5-15mg | 15mg+ |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Peak | Total |
|---|---|---|---|
| Oral | 30-90 min | 30-40 hrs | 30.5-41.5 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)
Opioid
5.4
Moderate+
5/10
Moderate euphoria with mild pain relief and itching/nausea, low sedation
Euphoria / Warmth
×3
7
euphoria
cognitive euphoria
mood lift
Analgesia
×2
4
analgesia
Sedation / Relaxation
×1
3
sedation
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
7–14 days for partial reset; full reset may take weeks — tolerance loss greatly increases overdose risk
Tolerance Decay
Full tolerance
1d
Half tolerance
21d
Baseline
~35d
Effects
Positive
- Analgesia
- Stimulation
Negative
- Dry Mouth
- Increased heart rate
- Insomnia
- Pupil dilation
- Itchiness
- Relaxant
- Pupil constriction
- Sedation
Positive
- Euphoria
- Mood lift
- Reduced anxiety
- Cognitive euphoria
- Wakefulness
Negative
- Constipation
- Anxiety
- Confusion
- Compulsive redosing
- Time distortion
Positive
- Increased music appreciation
- Color enhancement
- Tactile enhancement
- Brightened colour
Negative
- Light sensitivity
- Disinhibition
- Appetite suppression
- Dehydration
- Dulled perception
- Drifting
Combinations
Isomethadone's nerd page
Pharmacology, chemical data, effect profiles, and more
→