Nurses Compass
Drug Guide
Lacosamide
Classification
Therapeutic: Anticonvulsant
Pharmacological: Voltage-gated sodium channel blocker, analgesic
FDA Approved Indications
- Partial-onset seizures with or without secondarily generalized seizures
Mechanism of Action
Lacosamide selectively enhances slow inactivation of voltage-gated sodium channels, stabilizing hyperexcitable neuronal membranes and inhibiting repetitive neuronal firing.
Dosage and Administration
Adult: Start with 50 mg twice daily; increase gradually to a target dose of 200-400 mg/day based on response and tolerability.
Pediatric: Not approved for pediatric use.
Geriatric: Adjust dose based on renal function and tolerability; start at lower end of dosing range.
Renal Impairment: Reduce dose in renal impairment; monitor renal function.
Hepatic Impairment: Use with caution; no specific dose adjustment recommended.
Pharmacokinetics
Absorption: Rapidly absorbed, bioavailability approximately 100%.
Distribution: Widely distributed; volume of distribution ~55 L.
Metabolism: Minimal hepatic metabolism; primarily excreted unchanged in urine.
Excretion: Primarily via urine (~95%).
Half Life: approximately 13 hours.
Contraindications
- Hypersensitivity to lacosamide or other ingredients.
Precautions
- Use with caution in patients with cardiac arrhythmias, conduction block, or moderate to severe hepatic impairment.
- Monitor for suicidal ideation and behavior.
- Potential for CNS depression; caution with other CNS depressants.
Adverse Reactions - Common
- Dizziness (Frequent)
- Headache (Frequent)
- Nausea (Frequent)
- Diplopia (Frequent)
Adverse Reactions - Serious
- Elderly patients: prolongation of PR interval leading to atrioventricular block (rare) (Rare)
- Suicidal thoughts or behavior (Uncommon)
- Breathing difficulties (hypersensitivity reactions) (Rare)
Drug-Drug Interactions
- Other sodium channel blockers, CNS depressants, drugs that prolong PR interval (e.g., AV nodal blocking agents).
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Baseline ECG, renal function, mental status, history of cardiac arrhythmias.
Diagnoses:
- Risk for injury due to dizziness or somnolence.
- Risk for cardiac conduction abnormalities.
Implementation: Administer as prescribed, monitor for adverse effects, especially cardiac conduction and neuropsychiatric effects.
Evaluation: Assess seizure control, monitor for adverse reactions, adherence.
Patient/Family Teaching
- Take medication exactly as prescribed.
- Report signs of dizziness, vision changes, or mood changes.
- Do not abruptly stop medication.
- Avoid alcohol and CNS depressants unless directed.
Special Considerations
Black Box Warnings:
- Potential for available for cardiac conduction disturbances, including PR prolongation and atrioventricular block.
Genetic Factors: Patients with certain variants may have increased risk of cardiac side effects.
Lab Test Interference: May cause false increase in serum lab values (e.g., INR).
Overdose Management
Signs/Symptoms: Dizziness, ataxia, nystagmus, seizures, cardiac conduction delays.
Treatment: Supportive care, activated charcoal if early, cardiac monitoring, ensure airway patency, consider ECG for conduction issues.
Storage and Handling
Storage: Store at room temperature away from moisture, heat, and light.
Stability: Stable through expiration date when stored properly.