Home Drug Guide Phensuximide

Drug Guide

Generic Name

Phensuximide

Brand Names Milontin

Classification

Therapeutic: Anticonvulsant, Antiepileptic

Pharmacological: Succinamide derivative

FDA Approved Indications

  • Absence seizures (petit mal)

Mechanism of Action

Phensuximide works by inhibiting voltage-sensitive sodium channels in neurons, leading to suppression of abnormal neuronal firing that causes seizures.

Dosage and Administration

Adult: Initial dose of 250 mg twice daily, titrated based on response and tolerability.

Pediatric: Typically started at 10-20 mg/kg/day in divided doses, titrated cautiously.

Geriatric: Use with caution; start at lower doses and titrate slowly.

Renal Impairment: Adjust dose based on renal function; close monitoring recommended.

Hepatic Impairment: Use caution; no specific dosage adjustment but monitor liver function.

Pharmacokinetics

Absorption: Well absorbed orally.

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

Metabolism: Minimal hepatic metabolism.

Excretion: Primarily renally excreted unchanged.

Half Life: Approximately 10-24 hours.

Contraindications

  • Hypersensitivity to succinimides or any component of the formulation.

Precautions

  • History of hypersensitivity reactions, including rash or Stevens-Johnson syndrome.
  • Use with caution in patients with hepatic or renal impairment.
  • Monitor for signs of blood dyscrasias, such as leukopenia or anemia.

Adverse Reactions - Common

  • Gastrointestinal upset (nausea, vomiting) (Common)
  • Drowsiness, dizziness (Common)
  • Urinary frequency or urgency (Common)

Adverse Reactions - Serious

  • Blood dyscrasias (agranulocytosis, aplastic anemia) (Rare)
  • Stevens-Johnson syndrome/Toxic epidermal necrolysis (Rare)
  • Severe hypersensitivity reactions (Rare)

Drug-Drug Interactions

  • Valproic acid may increase levels of phensuximide.
  • Other anticonvulsants may have additive effects.

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

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

Diagnoses:

  • Risk of injury due to seizures.
  • Impaired skin integrity due to hypersensitivity reactions.

Implementation: Administer with food to reduce gastrointestinal upset, as prescribed. Monitor for adverse effects.

Evaluation: Assess seizure control and side effects regularly.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Do not discontinue abruptly to avoid seizure recurrence.
  • Report any signs of skin rash, sore throat, fever, unusual bleeding, or bruising.
  • Inform about possible drowsiness and avoid hazardous activities if affected.

Special Considerations

Black Box Warnings:

  • Serious dermatologic reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis, have been reported.

Genetic Factors: Genetic variations in drug metabolism may influence response.

Lab Test Interference: May affect liver function tests and blood counts.

Overdose Management

Signs/Symptoms: Drowsiness, vomiting, agitation, coma.

Treatment: Supportive care, activated charcoal if recent ingestion, and monitoring in a healthcare setting.

Storage and Handling

Storage: Store at room temperature, away from moisture and light.

Stability: Stable under recommended storage conditions.

🛡️ 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.