Tablet (Peganone; Discontinued)
- Strengths
- 250 mg
- Product note
- Strength in the cited 2010 archived label.
Ethotoin
Peganone · Discontinued
Historical antiseizure indications · Discontinued
Indication / use
- Label / evidence summary
- Discontinued. Historical label: tonic-clonic (grand mal) seizures and complex partial (psychomotor) seizures.
- Role
- Historical maintenance use · Discontinued
- Class
- Hydantoin antiseizure medication
Historical reference only. The linked FDA PDF is an archived label, not a current DailyMed product label. Discontinued marketing status does not by itself establish the reason for discontinuation or withdrawal of approval.
- Peganone tablets (Discontinued) Discontinued · historical U.S. label
Generalized tonic-clonic seizures, Focal seizures · No numeric age limits specified in this label · MaintenanceHistorical label: tonic-clonic and complex partial seizures; not current product availability.
Formulations & strengths
Archived U.S. label; historical strengths, not current availability.
Brand & formulation labels
Each link names the product and formulation it covers. Archived labels do not establish current availability.
Dosing & administration
- Adult / product-specific schedule
- Historical label: initially 1 g/day or less; increase gradually over several days. Usual maintenance 2–3 g/day in 4–6 divided doses after food.
- Pediatric
- Historical label: initial total no more than 750 mg/day; usual maintenance 500–1,000 mg/day in divided doses, individualized to age and weight. Higher totals were occasionally described. No numeric minimum age is stated.
- Titration / repeat dosing
- Historical dosing only. Increase conservatively and taper other antiseizure drugs gradually during any supervised conversion; avoid abrupt withdrawal.
- Dose basis
- Historical archived-label dosing for a discontinued drug; included for reference, not current prescribing.
Practical administration
- Product instructions
- Historical label: oral doses after food, spaced as evenly as practicable.
Dose adjustment & concentrations
- Renal impairment
- No numeric dose-adjustment algorithm is supplied in the cited label.
- Hepatic impairment
- Contraindicated with hepatic abnormalities.
- Serum reference information
- Historical suggested range 15–50 mcg/mL; the label explicitly states this is not well documented. Nonlinear kinetics complicate dose–level predictions.
Safety
- Boxed warning
- No boxed warning in the cited label.
- Contraindications
- Hepatic abnormalities or hematologic disorders.
- Serious precautions & monitoring
- Blood dyscrasias, liver injury, rash and suicidal thoughts or behavior. Archived label recommends initial and periodic blood counts / urinalysis and liver testing when clinically indicated.
Common / selected adverse effects
- Nausea / gastrointestinal symptoms
- Dizziness
- Diplopia
- Ataxia
- Rash
Selected label-reported effects; frequencies cannot be compared across drugs.
Drug interactions: toxicity & clinical action
| Partner / combination | Clinical effect | Clinical action |
|---|---|---|
| Other drugs affecting blood-cell production | Potential additive hematologic toxicity. | Archived label advises avoiding combinations where possible. |
| Coumarin anticoagulants | Interaction proposed by analogy with phenytoin, not documented specifically for ethotoin. | Use caution and appropriate anticoagulation monitoring; do not present the interaction as proven. |
Selected interactions; consult the full label and complete medication list.
Pregnancy & contraception
- Fetal / neonatal risk
- Archived label warns of fetal harm; drug-specific human data are limited. It also discusses possible neonatal coagulation problems and transfer into breast milk.
Clinical evidence
Research summaries describe studied populations and outcomes; they do not add indications or constitute treatment recommendations.
Product-label evidence
Trial summary
- Study design / duration
- No modern pivotal randomized trial is summarized in the cited label.
- Primary endpoint
- No quantified pivotal endpoint supplied in the cited label.
This profile uses product-label evidence; no pivotal journal publication is asserted.
Comparative evidence
- Findings
- No head-to-head efficacy comparison is summarized.
Mechanism of action
- The historical label proposes action similar to phenytoin: stabilization of seizure threshold and limitation of seizure spread. It does not establish a specific molecular target.
Pharmacology
Adult values unless specified. Vd/F denotes apparent oral distribution volume.
Pharmacokinetics
- Bioavailability
- Fairly rapidly absorbed, but the extent of oral absorption is unknown in the archived label.
- Elimination half-life
- 3–9 hours at concentrations below approximately 8 mcg/mL; the label also reports 6–9 hours in a dosing study. Saturable metabolism makes elimination concentration dependent.
- Volume of distribution
- Not quantified in the cited product label.
- Active metabolite(s)
- Metabolites are described, but their contribution to clinical antiseizure activity is not established in the archived label.
- Active-metabolite half-life
- No clinically established active-metabolite half-life supplied in the archived label.
- Protein binding
- Not quantified in the cited product label.
- Metabolism / elimination
- Hepatic, saturable N-deethylation and hydroxylation; major metabolites include 5-phenylhydantoin and p-hydroxyethotoin.
Values reflect the cited product and study population; they are not interchangeable across formulations.
Molecular structure
NIH PubChem structure and record ↗
Product history
- Initial U.S. approval
- April 22, 1957 — Peganone (NDA 010841)
- Market / formulation history
- FDA application lists Peganone products as Discontinued; this entry preserves the 2010 label, not a currently marketed product.
- Brands
- Peganone · Discontinued
- Manufacturer / marketer
- Lundbeck / Abbott in the archived label
- Generic availability
- No currently marketed U.S. product is identified in the cited FDA application.
- Related drugs
- Phenytoin is another hydantoin.
Sources & review status
Archived FDA label and product marketing status checked: 2026-09-27. Other profile sources reviewed: 2026-09-27 · label revision noted at that review: Archived FDA Peganone label: May 2010.. This is a draft reference; final review is pending.