Fen-Phen
Aliases: Phen/fen
Summary
Daily Fen-Phen use was linked to valvular heart disease and pulmonary hypertension via 5-HT2B receptor agonism by fenfluramine's metabolite norfenfluramine; the combination was withdrawn from market in 1997. Nearly 30% of users taking the combination for up to 24 months developed abnormal valve findings. Phentermine alone does not cause valvular damage and remains available for short-term obesity treatment.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | - | - | - | 37.5+/80+mg(notrecommended)+ |
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset |
|---|---|---|---|---|
| Oral | 20-60 min | 30-60 min | 1-3 hrs | 3-6 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)
Strong euphoria and anxiety/jitters with moderate stimulation, low focus
Tolerance
Tolerance Decay
Tolerance to appetite suppression develops faster than to cardiovascular side effects; rest periods of several weeks reduce (but do not eliminate) risks. Data synthesized from clinical and anecdotal sources; quantitative estimates approximate.
Cross-Tolerances
Effects
- Stimulation
- Pain relief
- Physical euphoria
- Tachycardia
- Dry mouth
- Restlessness
- Insomnia
- Fatigue
- Respiratory depression
- Sedation
- Wakefulness
- Motivation enhancement
- Euphoria
- Alertness enhancement
- Cognitive euphoria
- Anxiety suppression
- Reduced anxiety
- Anxiety
- Constipation
- Talkativeness
- Warmth
- Increased music appreciation
- Increased libido
- Appetite suppression
- Light sensitivity
- Disinhibition
- Dehydration
- Dulled perception
- Internal hallucination
- Warm flush