Home Drug Guide Trimethadione

Drug Guide

Generic Name

Trimethadione

Brand Names Tridione

Classification

Therapeutic: Anticonvulsant

Pharmacological: Hydantoin derivative

FDA Approved Indications

  • Absence seizures (petit mal)

Mechanism of Action

Trimethadione reduces neuronal hyperexcitability by inhibiting T-type calcium channels, thereby suppressing abnormal electrical activity associated with absence seizures.

Dosage and Administration

Adult: Initial dose: 300 mg twice daily, titrate based on response and tolerability.

Pediatric: Same as adults; dosing based on weight and age, usually starting at 150-300 mg/day divided into multiple doses.

Geriatric: Use with caution due to potential for increased side effects; start at lower doses and titrate slowly.

Renal Impairment: Adjust dose as needed; monitor renal function.

Hepatic Impairment: Use cautiously; no specific adjustments but monitor liver function.

Pharmacokinetics

Absorption: Rapidly absorbed from gastrointestinal tract.

Distribution: Widely distributed in body tissues, crosses the blood-brain barrier.

Metabolism: Metabolized minimally in the liver.

Excretion: Primarily excreted unchanged in urine.

Half Life: Approximately 50-72 hours in adults, allowing for once or twice daily dosing.

Contraindications

  • Hypersensitivity to trimethadione or related compounds.
  • History of blood dyscrasias.

Precautions

  • Monitor blood counts regularly due to risk of blood dyscrasias.
  • Use with caution in hepatic or renal impairment.
  • Pregnancy Category D: risk to fetus; weigh benefits vs. risks.

Adverse Reactions - Common

  • Drowsiness, dizziness (Common)
  • Gastrointestinal disturbances (Common)

Adverse Reactions - Serious

  • Blood dyscrasias (aplastic anemia, agranulocytosis) (Rare)
  • Hepatotoxicity (Rare)
  • Dermatological reactions, including Stevens-Johnson syndrome (Rare)

Drug-Drug Interactions

  • CNS depressants, increasing sedation.
  • Valproic acid may increase serum levels of trimethadione.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor seizure frequency, blood counts, liver and renal function.

Diagnoses:

  • Risk for injury due to seizures or adverse effects.
  • Impaired laboratory parameters (blood counts, liver enzymes).

Implementation: Administer with food to reduce gastrointestinal upset. Educate patient on adherence and side effects.

Evaluation: Assess seizure control and monitor for adverse effects regularly.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Report signs of blood dyscrasias (e.g., sore throat, fever, unusual bleeding).
  • Avoid alcohol and CNS depressants.
  • Regular blood tests are necessary.

Special Considerations

Black Box Warnings:

  • Risk of blood dyscrasias, including aplastic anemia and agranulocytosis.

Genetic Factors: No specific genetic factors identified.

Lab Test Interference: May falsely elevate certain laboratory liver and blood parameters.

Overdose Management

Signs/Symptoms: Drowsiness, ataxia, nausea, vomiting, dizziness, or coma in severe cases.

Treatment: Supportive care, activated charcoal if early, and close monitoring. Hemodialysis may be considered in severe overdose.

Storage and Handling

Storage: Store at room temperature, 20-25°C (68-77°F).

Stability: Stable under recommended storage conditions; check expiry date.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.