Are levetiracetam (Keppra) and amitriptyline safe for a patient with a seizure disorder?

Levetiracetam (Keppra) and Amitriptyline Combination Safety in Seizure Disorders

Yes, levetiracetam (Keppra) is safe and appropriate for seizure disorders, but amitriptyline requires caution as it can lower the seizure threshold and should generally be avoided or used with careful monitoring in patients with epilepsy.

Levetiracetam Safety Profile

Levetiracetam is well-established as a safe and effective antiseizure medication with several advantages 1, 2, 3:

• Approved indications: Partial onset seizures (with or without secondary generalization), myoclonic seizures in juvenile myoclonic epilepsy, and primary generalized tonic-clonic seizures 2, 3
• Favorable pharmacokinetics: No cytochrome P450 interactions, minimal drug-drug interactions, predominantly renal elimination 4, 5
• Loading doses: Safe at 1,500 mg oral or up to 60 mg/kg IV, with rapid therapeutic effect 1

Common Adverse Effects

The most frequently reported side effects include 3:

• Somnolence (15% vs 8% placebo)
• Asthenia/fatigue (15% vs 9% placebo)
• Dizziness (9% vs 4% placebo)
• Behavioral effects: irritability, agitation, hostility (12-15% risk, higher in learning disabled individuals or those with psychiatric history) 5

Critical point: Levetiracetam does NOT lower the seizure threshold and has no significant drug interactions that would compromise seizure control 4, 5.

Amitriptyline Concerns in Seizure Disorders

Seizure Threshold Lowering

Amitriptyline and other tricyclic antidepressants can lower the seizure threshold, making them problematic for patients with epilepsy 6. The FDA guidance states:

• SSRIs "should be used cautiously in patients with a history of a seizure disorder" 6
• While this statement specifically addresses SSRIs, tricyclic antidepressants like amitriptyline carry even greater seizure risk than SSRIs

Safer Alternatives

If treating comorbid depression, anxiety, or neuropathic pain in a patient with seizures, consider 6:

• SSRIs (fluoxetine, sertraline, escitalopram) - lower seizure risk than tricyclics
• SNRIs (duloxetine, venlafaxine) - for neuropathic pain with lower seizure risk
• Gabapentin or pregabalin - for neuropathic pain without lowering seizure threshold

Clinical Recommendations

If Patient is Already on Both Medications:

1. Assess seizure control: Has there been any increase in seizure frequency since starting amitriptyline?
2. Monitor closely: Watch for breakthrough seizures, especially in the first weeks after dose changes
3. Consider alternatives: Evaluate whether amitriptyline can be replaced with a safer option for the indication being treated
4. Optimize levetiracetam: Ensure therapeutic dosing (typically 1,000-3,000 mg/day in divided doses) 1, 3

If Considering Starting This Combination:

1. Avoid amitriptyline if possible - choose alternatives with lower seizure risk
2. If amitriptyline is essential:
   • Start at lowest effective dose
   • Titrate slowly with close monitoring
   • Ensure levetiracetam is at therapeutic levels
   • Educate patient about seizure warning signs
   • Consider more frequent follow-up initially

Monitoring Parameters

• Seizure frequency and characteristics
• Behavioral changes (levetiracetam can cause irritability/hostility) 3
• Somnolence (both drugs can cause this)
• Renal function (for levetiracetam dosing adjustments if needed)

Important Caveats

Levetiracetam-specific warnings 7, 3:

• The package insert mentions lowering seizure threshold, but published studies show epileptic patients on anticonvulsants do NOT show increased seizure frequency when levetiracetam is added
• Best to initiate after seizure disorder is controlled with anticonvulsants
• Discontinuation syndrome possible - taper gradually, don't stop abruptly

Drug interaction note: While levetiracetam has minimal interactions, one recent study suggests potential interaction with carbamazepine leading to carbamazepine toxicity 8. However, no significant interaction with amitriptyline has been documented.