Medication Description

Keppra (levetiracetam) is an antiepileptic drug used to manage and treat seizures. It is available in various forms including oral tablets, oral solution, and intravenous injection. The medication works by stabilizing electrical activity in the brain, reducing the incidence of seizures.

Pharmacological Properties

Keppra is classified as a pyrrolidine derivative. It exerts its anticonvulsant effects by inhibiting certain neurotransmitter processes. The exact mechanism of action is not fully understood but involves modulation of synaptic vesicle protein 2A.

Pharmacokinetics

Keppra has a rapid absorption rate and nearly complete bioavailability when administered orally. Plasma peak levels are typically achieved within one to two hours post-ingestion. The drug is minimally bound to plasma proteins and is primarily excreted renally.

Half-life

The elimination half-life of Keppra in adults is approximately 6 to 8 hours. This half-life is extended in individuals with impaired renal function, necessitating dosage adjustments in such populations.

Clinical Indications

Keppra is indicated for the treatment of partial-onset seizures in adults and children aged four years and older. It is also prescribed for myoclonic seizures in adults and adolescents aged 12 years and older with juvenile myoclonic epilepsy. Additionally, Keppra is utilized for primary generalized tonic-clonic seizures in individuals six years and older.

Monotherapy Usage

Keppra can be used as monotherapy in the treatment of partial-onset seizures in patients who have not responded to other anticonvulsant medications. Monotherapy with Keppra is typically initiated at a lower dose and gradually increased based on clinical response.

Adjunctive Therapy

In cases of refractory epilepsy, Keppra is often used as an adjunctive therapy. It has shown efficacy in reducing seizure frequency when added to the patient’s existing antiepileptic regimen.

Dosage and Administration

Keppra dosage varies based on the patient’s age, condition being treated, and renal function. Adult patients typically start at 500 mg twice daily, with incremental increases every two weeks until the desired therapeutic effect is achieved. Pediatric dosing is weight-based.

Oral Administration

The oral tablets and solution should be taken with or without food. Consistency in timing of doses is critical to maintaining stable plasma levels. The oral solution offers flexibility for patients who have difficulty swallowing tablets.

Intravenous Administration

Intravenous Keppra is used when oral administration is not feasible. The IV formulation should be diluted before use and administered as a 15-minute infusion. Transition from IV to oral should maintain the same total daily dosage.

Drug Interactions

Keppra exhibits minimal interaction with other medications. It does not significantly induce or inhibit cytochrome P450 enzymes, making it a favorable choice for patients on multiple drugs. Concomitant use with other CNS depressants may potentiate sedative effects.

Pregnancy and Lactation

Keppra has been categorized as a Pregnancy Category C drug. Data on human pregnancies are limited, but animal studies have shown some adverse effects. It is excreted in breast milk, and caution is advised when administered to breastfeeding women.

Co-morbid Conditions

Patients with renal impairment require dosage adjustments based on creatinine clearance levels. Keppra can be used cautiously in individuals with hepatic impairment, although it is metabolized minimally by the liver.

Formulations Available

Keppra is available in immediate-release tablets, extended-release tablets, oral solution, and intravenous formulations. Available strengths for oral tablets include 250 mg, 500 mg, 750 mg, and 1,000 mg. The oral solution comes as a 100 mg/mL concentration.

Extended-release Tablets

The extended-release tablets provide a once-daily dosing option, potentially improving adherence. It ensures a more consistent release of the medication over 24 hours, which may reduce peak-related adverse effects.

Storage and Handling

Keppra should be stored at room temperature, away from light and moisture. The oral solution requires reconstitution and should be shaken well before use. Intravenous formulations should be inspected for particulate matter before administration.

Patient Counseling Information

Patients should be advised to take Keppra at the same time each day to maintain even drug levels. Missed doses should be taken as soon as remembered unless it is near the time for the next dose. Patients should never double dose.

Common Adverse Effects

Notable side effects include drowsiness, dizziness, and fatigue. Patients may also experience gastrointestinal disturbances such as nausea and vomiting. Behavioral changes such as irritability and aggression have been reported.

Monitoring Requirements

Regular monitoring of renal function is advised, especially in patients with pre-existing renal conditions. Healthcare providers should also assess patients for any signs of depression or mood changes.

Discontinuation Considerations

Keppra should be tapered off gradually rather than stopping abruptly. Abrupt discontinuation can lead to increased seizure frequency or status epilepticus. A gradual dose reduction over several weeks is recommended.

Clinical Trials and Efficacy

Multiple clinical trials have demonstrated the efficacy of Keppra in reducing seizure frequency in both partial and generalized epilepsy. In pediatric populations, it has shown a favorable safety profile and significant seizure reduction.

Alternative Medications

For patients who may not tolerate Keppra, alternative antiepileptic drugs include carbamazepine, lamotrigine, and valproate. Each medication comes with its own efficacy profile and side effect considerations.