Ethosuximide

A to Z Drug Facts

Ethosuximide

	Action
	Indications
	Contraindications
	Route/Dosage
	Interactions
	Lab Test Interferences
	Adverse Reactions
	Precautions
Patient Care Considerations
	Administration/Storage
	Assessment/Interventions
	Patient/Family Education

(ETH-oh-SUX-ih-mide)

Zarontin

Class: Anticonvulsant/succinimide

Action Elevates seizure threshold and suppresses paroxysmal spike and wave activity associated with lapses of consciousness common in absence (petit mal) seizures.

Indications Control of absence (petit mal) seizures.

Contraindications Hypersensitivity to succinimides.

Route/Dosage

ADULTS & CHILDREN ³ 6 YR: PO 500 mg/day. Optimal dose for most children is 20 mg/kg/day. Maintenance therapy: Individualize dose. Increase daily dose slowly by 250 mg q 4 to 7 days until control is achieved with minimal side effects. Doses exceeding 1.5 g/day should be administered in divided doses under strict medical supervision. CHILDREN 3–6 YR: INITIAL DOSE: PO 250 mg/day.

Interactions

Hydantoins: May increase serum hydantoin levels. Primidone: Lower primidone and phenobarbital levels may occur.

Lab Test Interferences None well documented.

Adverse Reactions

CNS: Drowsiness; headache; dizziness; euphoria; hiccoughs; irritability; hyperactivity; lethargy; fatigue; ataxia; psychological disturbances such as sleep disorders; night terrors; poor concentration; aggressiveness. DERM: Urticaria; Stevens-Johnson syndrome; systemic lupus erythematosus; pruritic erythematous rash; hirsutism. EENT: Myopia. GI: Anorexia; GI upset; nausea; vomiting; cramps; epigastric and abdominal pain; weight loss; gum hypertrophy; tongue swelling. GU: Vaginal bleeding; microscopic hematuria. HEMA: Leukopenia; agranulocytosis; pancytopenia; bone marrow suppression; eosinophilia.

Precautions

Pregnancy: Anticonvulsant drugs have been observed to increase the incidence of birth defects. Hematologic effects: Blood dyscrasias, including fatal cases, have occurred. Periodic blood counts should be done. Hepatic or renal impairment: Use caution and perform periodic function tests. Lupus: Cases of systemic lupus erythematosus have occurred. Withdrawal: Do not withdraw drug abruptly as this may precipitate absence (petit mal) status; proceed slowly when increasing or decreasing dose.

PATIENT CARE CONSIDERATIONS

Administration/Storage

Dosage should be increased in small increments.
If GI upset occurs, give with food or milk.
Store capsules in tight containers and syrup in light-resistant containers at room temperature. Avoid freezing.

Assessment/Interventions

Obtain patient history, including drug history and any known allergies.
Assess location, duration and characteristics of seizure activity.
Document baseline CBC, hepatic function and urinalysis, and monitor routinely throughout course of therapy.
Observe frequently for occurrence of seizure activity and report findings to physician.
Ensure that patient is protected from injury. Supervise and assist with ambulation if dizziness and drowsiness are problems. Pad siderails and head of bed with towels or blanket for patients who experience seizures during night.
Assess patient's mood, behavior patterns and facial expressions. Patients with history of psychiatric disorders have an increased risk of developing behavioral changes.
Observe for GI symptoms, drowsiness, ataxia, dizziness and other neurologic side effects.

OVERDOSAGE: SIGNS & SYMPTOMS
	Acute overdose: Confusion; sleepiness; unsteadiness; flaccid muscles; coma with slow, shallow respiration; nausea and vomiting Chronic overdose: Skin rash; confusion; ataxia; dizziness; drowsiness; irritability; poor judgment; periorbital edema; proteinuria; hepatic dysfunction; fatal bone marrow aplasia; hematuria; nephrosis

Patient/Family Education

Instruct patient to take medication with food to minimize GI upset.
Advise patient to carry wallet identification card or Medi-Alert bracelet, describing disease process and medication regimen, physician's name and telephone number.
Emphasize importance of follow-up exams to monitor progress and side effects.
Explain that medication may change color of urine to pink, red or red-brown, and assure that this is not harmful.
Instruct patient to report these symptoms to physician: skin rash, sore throat, fever, unusual bleeding or bruising, swollen glands or pregnancy.
Tell patient to avoid intake of alcoholic beverages or other CNS depressants.
Advise patient that drug may cause drowsiness and to use caution while driving or performing other tasks requiring mental alertness.
Instruct patient not to take otc medications without consulting physician.