Indications for Use
Keppra (Levetiracetam) is primarily indicated for the treatment of partial-onset seizures, which may occur with or without secondary generalization. Additionally, it is used in the management of myoclonic seizures in patients with juvenile myoclonic epilepsy and in primary generalized tonic-clonic seizures in patients with idiopathic generalized epilepsy.
Mechanism of Action
Levetiracetam, the active ingredient in Keppra, exerts its antiepileptic effects by binding to the synaptic vesicle protein SV2A. This action inhibits vesicle exocytosis and reduces neurotransmitter release, decreasing neuronal excitability and preventing seizure propagation.
Dosage Information
The initial adult dosage for partial-onset seizures starts at 500 mg twice daily, with potential increases every two weeks by 1,000 mg per day, not exceeding 3,000 mg per day. Pediatric doses for children 4 years of age and older generally begin at 20 mg/kg divided into two doses, with gradual increases based on weight and response.
Administration Guidelines
Keppra can be administered with or without food. The tablets should be swallowed whole with water. The solution is to be measured accurately using a dosing syringe or a measuring device provided for accuracy. Consistency in administration times is recommended to maintain stable plasma levels.
Common Side Effects
Frequently encountered side effects include dizziness, fatigue, and somnolence. Mood changes such as irritability and aggression, as well as gastrointestinal issues like nausea and vomiting, may occur. These side effects usually diminish with continued use.
Serious Adverse Effects
Serious but less common side effects include severe mood changes, suicidal thoughts, and behavioral abnormalities. Other severe reactions can include dermatological reactions such as Stevens-Johnson syndrome or toxic epidermal necrolysis, and hematologic abnormalities like pancytopenia.
Drug Interactions
Keppra has minimal interaction with other antiepileptic drugs (AEDs). It also does not significantly induce or inhibit cytochrome P450 enzymes, reducing the risk of metabolic interactions. No significant interaction with the oral contraceptive pill has been observed.
Compatibility with Other Drugs
Keppra can be safely co-administered with drugs like topiramate, gabapentin, and lamotrigine. Adjustments in dosage are typically not necessary when used concurrently with these medications. Always monitor for increased side effects when combining AEDs.
Renal Impairment Adjustments
Dosage adjustments are crucial for patients with renal impairment. For mild to moderate renal impairment, a 50% decrease in usual dosing is recommended. In severe renal impairment or end-stage renal disease, dosages may be reduced by approximately 75%, and supplemental doses should be given post-dialysis.
Use During Pregnancy
Keppra falls under Pregnancy Category C, indicating that risk cannot be ruled out. Use should be based on the consideration of the benefits versus the potential risks to the fetus. Animal studies have shown adverse effects, but human data is limited.
Breastfeeding Recommendations
Keppra is excreted into breast milk. The decision to continue breastfeeding or discontinue Keppra should be based on the importance of the drug to the mother versus the potential risk to the infant. Monitoring of breastfed infants for adverse effects is recommended.
Storage Instructions
Store at room temperature, typically between 15-30°C (59-86°F), away from direct light and moisture. Keep out of reach of children. The oral solution should be used within a certain period after opening, usually 7 months.
Missed Dose Advice
If a dose is missed, it should be taken as soon as remembered. If it is close to the time for the next dose, skip the missed dose and resume the regular dosing schedule. Do not double doses to catch up.
Overdose Management
Symptoms of overdose may include drowsiness, agitation, aggression, decreased consciousness, and respiratory depression. Immediate medical attention is essential. Treatment is symptomatic, with gastric lavage and supportive measures recommended.
Monitoring Therapy
Regular monitoring of renal function is advised, particularly in the elderly. Periodic assessments of mood and behavioral changes are crucial due to potential psychiatric adverse effects. Therapeutic blood level monitoring is not typically necessary.
Pediatric Use Parameters
Use in children is approved for those aged 1 month and older for partial-onset seizures and 12 years and older for myoclonic and tonic-clonic seizures. Dosing is weight-based, with close monitoring for side effects due to potential variability in metabolic rates and sensitivity.
Geriatric Use Considerations
Dosage adjustments may be necessary due to declining renal function associated with aging. The lowest effective dose should be used, with careful titration and monitoring for increased side effects like dizziness and somnolence.
Drug Formulations Available
Keppra is available in various formulations including immediate-release tablets (250 mg, 500 mg, 750 mg, 1,000 mg), extended-release tablets (500 mg, 750 mg), and oral solution (100 mg/ml). The choice of formulation depends on the patient’s needs and therapy goals.
Patient Counseling Information
Patients should be counseled on adherence to the prescribed regimen and advised not to abruptly discontinue the medication due to the risk of seizure recurrence. Inform them about potential side effects and instruct them to report any unusual changes in mood or behavior.
Alcohol Consumption Advisory
Alcohol consumption may potentiate the sedative effects of Keppra and can increase the risk of seizures. Patients should be advised to limit or avoid alcohol while taking Keppra and to discuss any concerns with their healthcare provider.