Keppra Tablets and Oral Solution Bioequivalence
Yes, Keppra (levetiracetam) tablets and oral solution are bioequivalent and can be used interchangeably without dose adjustment. 1
Pharmacokinetic Equivalence
The FDA drug label explicitly states that "levetiracetam tablets and oral solution are bioequivalent," meaning they provide identical drug exposure and can be substituted 1:1 without concern for therapeutic differences. 1
Both formulations demonstrate 100% oral bioavailability, with rapid and complete absorption after oral administration, achieving peak plasma concentrations in approximately one hour in fasted subjects. 1
The extent of absorption is identical between tablets and oral solution, though food may decrease Cmax by 20% and delay Tmax by 1.5 hours for both formulations—this does not affect overall bioavailability or clinical efficacy. 1
Clinical Implications for Switching
Patients can be switched directly between tablets and oral solution at the same total daily dose without titration or monitoring for loss of seizure control. 1
The linear pharmacokinetics of levetiracetam (studied across 500-5000 mg dose range) ensure predictable drug exposure regardless of formulation, with steady state achieved after 2 days of twice-daily dosing. 1
Levetiracetam's minimal protein binding (<10%) and lack of significant drug-drug interactions further support the safety of formulation switching without concern for altered pharmacokinetics. 1
Practical Considerations
The oral solution may be preferred for patients with dysphagia, those requiring nasogastric/gastrostomy tube administration, or when precise dose titration is needed (particularly in pediatric populations). 1
Tablet formulations offer convenience for most ambulatory patients and may improve adherence due to ease of administration. 2
Unlike concerns about brand-to-generic switching (where some case reports suggest potential loss of seizure control), switching between Keppra formulations (tablet vs. solution) carries no such risk since both are manufactured by the same company with identical active ingredient bioavailability. 1, 3