02662nas a2200313   4500000000100000008004100001260001300042653003000055653002500085653001200110653004400122653002100166653001200187653002700199653000900226653000900235653002500244653001700269100001500286700001600301700001600317700001800333700001500351245009900366300001000465490000700475520185200482022001402334       2000                            d  c2000 Aug10aAdministration, Cutaneous10aAdministration, Oral10aAnimals10aAnti-Inflammatory Agents, Non-Steroidal10aArea Under Curve10aDapsone10aInfusions, Intravenous10aMale10aRats10aRats, Sprague-Dawley10aTime Factors1 aHelton D R1 aOsborne D W1 aPierson S K1 aBuonarati M H1 aBethem R A00aPharmacokinetic profiles in rats after intravenous, oral, or dermal administration of dapsone.  a925-90 v283 a<p>Dapsone is a potent anti-inflammatory and antibacterial agent that has been used extensively in the oral treatment of leprosy and dermatitis herpetiformis. This study compared the pharmacokinetic profile of dapsone in rats given a single oral or i.v. 12 mg/kg dose (n = 8/group) or a single dermal application of 12 or 60 mg/kg (n = 12/group) in an aqueous gel application medium containing 10 or 25% diethylene glycol monoethyl ether (DGME). Blood samples (200 microl) were collected via tail vein from each rat and pooled at intervals up to the 24-h period. A terminal blood sample was collected by cardiac puncture from each animal. Plasma concentrations of dapsone were determined by liquid chromatography atmospheric pressure ionization tandem mass spectroscopy. There was no treatment-related overt toxicity observed in any of the animals. Peak levels were reached 1 h after oral dosing (4890 ng/ml), and 6 to 8 h after dermal application, with Cmax values of 1.62, 5.56, and 12.8 ng/ml, for 12 mg/kg at 10 or 25% DGME, and for 60 mg/kg at 25% DGME, respectively. Bioavailability was calculated at 78% after oral dosing and <1% after dermal application. Apparent elimination half-lives (t(1/2))s were similar after i.v. and oral dosing. Both the calculated area under the plasma concentration versus time curve up to 24 h and Cmax values were 3- to 4-fold higher in the dermal application group administered 12 mg/kg dapsone in 25 versus 10% DGME gel, whereas the calculated area under the plasma concentration versus time curve up to 24 h and Cmax values for the 60 mg/kg group were only 3.3- and 2.3-fold greater than those obtained after application of 12 mg/kg in 25% DGME. These results show that both systemic exposure and peak plasma concentrations of dapsone are minimized by dermal versus oral administration of the compound.</p>  a0090-9556