Nurses Compass
Drug Guide
Levetiracetam
Classification
Therapeutic: Anticonvulsant / Antiepileptic
Pharmacological: Additive neurotransmitter release inhibitor (exact mechanism unclear)
FDA Approved Indications
- Partial-onset seizures in epilepsy
- Myoclonic seizures in juvenile myoclonic epilepsy
- Tonic-clonic seizures in primary generalized epilepsy
Mechanism of Action
Levetiracetam's exact mechanism is not fully understood, but it is believed to modulate synaptic neurotransmitter release by binding to the synaptic vesicle protein SV2A, which inhibits nerve conduction across abnormal neuronal firing, stabilizing neuronal activity.
Dosage and Administration
Adult: Initial dose usually 500 mg twice daily, titrated up to 1000-3000 mg/day based on response and tolerability.
Pediatric: Dosing varies; typically begins at 10 mg/kg twice daily, titrated up as needed.
Geriatric: Start at lower doses due to increased sensitivity, with careful titration.
Renal Impairment: Dose reduction needed in renal impairment; dosing based on renal function.
Hepatic Impairment: No dose adjustment necessary as hepatic metabolism is minimal.
Pharmacokinetics
Absorption: Rapid and complete in fasting state; food does not significantly affect absorption.
Distribution: Low plasma protein binding (~10%).
Metabolism: Minimal hepatic metabolism; primarily excreted unchanged.
Excretion: Renally excreted; dose adjustments required for renal impairment.
Half Life: Approximately 6-8 hours.
Contraindications
- Known hypersensitivity to levetiracetam or any component of the formulation.
Precautions
- History of psychiatric disorders; monitor for behavioral changes.
- Use with caution in renal impairment; adjust dose accordingly.
Adverse Reactions - Common
- Somnolence (2-17%)
- Weakness (1-10%)
- Dizziness (4-14%)
- Infection (e.g., upper respiratory) (6-12%)
Adverse Reactions - Serious
- Psychiatric symptoms ( agitation, depression, mood changes) (less common, monitor closely)
- Severe allergic reactions (rare)
Drug-Drug Interactions
- Minimal. No significant CYP450 interactions.
- Valproic acid may increase levetiracetam levels.
Drug-Food Interactions
- No significant interactions
Drug-Herb Interactions
- Limited data; interaction potential unknown
Nursing Implications
Assessment: Monitor seizure control, behavioral changes, and suicidal ideation.
Diagnoses:
- Risk for injury related to seizure activity or adverse effects.
- Altered mental status related to medication side effects.
Implementation: Administer doses as prescribed. Educate patient about adherence and side effect reporting.
Evaluation: Assess frequency and severity of seizures, monitor for adverse effects and behavioral changes.
Patient/Family Teaching
- Take medication regularly at the same time each day.
- Report any mood changes, behavioral alterations, or the emergence of suicidal thoughts.
- Do not stop medication abruptly.
- Inform about potential side effects like somnolence, dizziness, and behavioral changes.
Special Considerations
Black Box Warnings:
- Psychiatric and behavioral reversals have been reported, including aggression, agitation, irritability, and depression.
Genetic Factors: No known genetic contraindications but consider pharmacogenetic research in the future.
Lab Test Interference: Minimal; does not interfere with common lab tests.
Overdose Management
Signs/Symptoms: Dizziness, decreased consciousness, respiratory depression, possibly coma.
Treatment: Supportive care, airway management, dialysis may be considered in severe cases to enhance elimination.
Storage and Handling
Storage: Store at room temperature 20-25°C (68-77°F); keep away from moisture and light.
Stability: Stable for at least 24 months when stored properly.