Systemic Exposure

In a pharmacokinetic study in healthy volunteers,
Minimal systemic exposure with FLECTOR Patch1
After 4 days of repeated dosing with FLECTOR Patch, systemic exposure of diclofenac was <1% of the systemic exposure with a single 50-mg oral dose of diclofenac sodium.
The clinical significance of these pharmacokinetic data is unknown.
Data on File, Pfizer Inc. A single-center, open-label, randomized study comparing the systemic bioavailability of FLECTOR Patch at steady state with a marketed 50-mg oral diclofenac sodium tablet after 1 dose in 24 healthy subjects. All 24 subjects applied FLECTOR Patch every 12 hours for 4 days, and serial blood samples were collected up to 48 hours postdose to determine mean steady-state values of maximum, minimum, and average plasma concentrations (Cmax, Cmin, Cavg), and area under the curve (AUC). In a crossover design, 12 subjects received 1 dose of 50-mg oral diclofenac sodium, and serial blood samples were collected up to 12 hours to determine Cmax, Time to Cmax (Tmax), drug elimination half-life (T1/2), and AUCt.
 
REFERENCE
1. Rusca A, Mautone G, Sun S, Magelli M, Johnson F. Comparison of plasma pharmacokinetics of FLECTOR patch (diclofenac epolamine topical patch) and or Voltaren (diclofenac sodium enteric-coated tablets) in healthy volunteers [abstract 279]. J Pain. 2008;9(4 suppl 2):45.