Fenfluramine
Limited data
Limited data
Sparse data. Doses and effects may be unreliable or untested.
- 1 source
- duration data present
- 20 combo interactions documented
- PubChem toxicity data
- dose data not in PW/TripSit (unverifiable)
- 1 source
- duration data present
- 20 combo interactions documented
- PubChem toxicity data
- dose data not in PW/TripSit (unverifiable)
Aliases: Pondimin, Fintepla
Summary
Fenfluramine was withdrawn from market as an appetite suppressant in 1997 due to cardiotoxicity (valvular heart disease and pulmonary hypertension). Reintroduced in 2020 for seizures associated with Dravet syndrome and Lennox-Gastaut syndrome at lower therapeutic doses. Available only through restricted REMS program requiring cardiac monitoring via echocardiogram.
Dose Information
| ROA | Threshold |
|---|---|
| Oral | 2mg |
Only a threshold dose is documented for this substance — the smallest amount with a noticeable effect. There is no published light/common/strong ladder to show above it.
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset | Total |
|---|---|---|---|---|---|
| Oral | 30-60 min | 1-2 hrs | 3-5 hrs | 3-6 hrs | 7.5-14 hrs |
Add to PsychonautWiki Journal
The PsychonautWiki Journal logging app doesn't include every substance. To track Fenfluramine there, start adding an ingestion, search for the name, and choose to add it as a custom substance. Paste these values:
Fenfluramine Source: SubstanceSearch (substancesearch.com) Oral dose (mg): threshold 2 Oral duration: onset 0.5-1h · come-up 1-2h · peak 3-5h · offset 3-6h · total 7.5-14h · after-effects 6-12h Note: ranges are harm-reduction guidance, not a prescription. Start low, go slow, and test your substances.
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.
Tolerance
Tolerance Decay
Robust human data describing pharmacodynamic tolerance to fenfluramine’s antiseizure effect are lacking; some tolerance to anorectic effects likely develops with repeated exposure, as seen historically with serotonergic anorectics, but magnitude and timeline are poorly characterized. Treat as unknown; avoid dose escalation outside medical guidance.
Cross-Tolerances
Effects
- Muscle relaxation
- Anxiolytic
- Muscle Relaxant
- Physical euphoria
- Lethargy
- Nausea
- Motor impairment
- Respiratory depression
- Sedation
- Sedative
- Euphoria
- Anxiety suppression
- Anxiety
- Dizziness
- Cognitive impairment
- Amnesia
- Motor control loss
- Thought deceleration
- Decreased arousal
- Time distortion
- Appetite suppression
- Disinhibition
- Decreased Libido
- Acuity Suppression
- Visual acuity suppression
- Hallucinations
- Dulled perception
- Perception of bodily heaviness
- Appetite fluctuation
Combinations
Cross-Check Fenfluramine with another substanceHelpful Links
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