Comparative Pharmacology
Head-to-head clinical analysis: LYRICA versus TOPAMAX.
Head-to-head clinical analysis: LYRICA versus TOPAMAX.
LYRICA vs TOPAMAX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Binds to the α2-δ subunit of voltage-gated calcium channels, reducing calcium influx and inhibiting release of excitatory neurotransmitters including glutamate, norepinephrine, and substance P.
Antiepileptic; modulates voltage-gated sodium channels, enhances GABA-A activity, antagonizes AMPA/kainate glutamate receptors, weakly inhibits carbonic anhydrase.
Oral: 75-150 mg twice daily or 50-100 mg three times daily; maximum 600 mg/day. Start at 75 mg twice daily.
Initial dose 25 mg orally twice daily; titrate by 25-50 mg weekly to effective dose; usual maintenance dose 200-400 mg/day divided twice daily; maximum 1600 mg/day.
None Documented
None Documented
Terminal elimination half-life is 6.3 hours (range 5.5–6.7 hours) in patients with normal renal function. Half-life increases in renal impairment (up to 48 hours in anuria).
Terminal elimination half-life is 21 hours (range 18-23 hours). Linear pharmacokinetics. Half-life is prolonged in renal impairment (CrCl <70 mL/min: ~35 hours).
Renal excretion of unchanged drug accounts for approximately 90% of elimination; less than 1% is secreted in feces or bile. Dose adjustment required in renal impairment (CrCl <60 mL/min).
Renal: ~70% (unchanged drug); remainder as metabolites. Biliary/fecal: minimal (<5%).
Category C
Category C
Anticonvulsant
Anticonvulsant