Patch containing anti-inflammatory agent

Abstract

An antiinflammatory-containing plaster comprising 5-40% by mass of a styrene-isoprene-styrene block copolymer, 1-25% by mass of a high molecular weight polyisobutylene, 0.5-24% by mass of a low molecular weight polyisobutylene, 3-50% by mass of a tackifier, 20-70% by mass of a plasticizer, 0.01-7% by mass of a dispersant, and 0.1-8% by mass of an antiinflammatory having a carboxyl group or a salt thereof, but which contains no L-menthol, wherein the medicament release rate at one hour after the start of test is 20-64% by mass and the medicament release rate at three hours after the start of test is 40-93% by mass according to the water-releasing test using a rotating cylinder described in the release test as prescribed in United State Pharmacopoeia.

1 . An antiinflammatory-containing plaster comprising 5-40% by mass of a styrene-isoprene-styrene block copolymer, 1-25% by mass of a high molecular weight polyisobutylene, 0.5-24% by mass of a low molecular weight polyisobutylene, 3-50% by mass of a tackifier, 20-70% by mass of a plasticizer, 0.01-7% by mass of a dispersant, and 0.1-8% by mass of an antiinflammatory having a carboxyl group or a salt thereof as the medicament, but which contains no L-menthol.  
     
     
         2 . The plaster according to  claim 1 , wherein the antiinflammatory having a carboxyl group or a salt thereof is at least one member antiinflammatory selected from the group consisting of indomethacin, ketoprofen, flurbiprofen, diclofenac, loxoprofen, ketorolac, and the salts of the foregoing and the blending proportion of the antiinflammatory is 0.5-5% by mass.  
     
     
         3 . The plaster according to  claim 1 , wherein the medicament release rate at one hour after the start of test is 20-64% by mass and the medicament release rate at three hours after the start of test is 40-93% by mass when the water-releasing test using a rotating cylinder described in the release test as prescribed in United State Pharmacopoeia is carried out under the following conditions: 
 Test solution: distilled water    Solution temperature: 32±0.5° C.    The distance between the lower end of cylinder and the inner bottom surface of container: 12±2 mm    The number of revolutions: 50 rpm.    
     
     
         4 . The plaster according to  claim 3 , wherein the medicament release rate at one hour after the start of test is 30-65% by mass and the medicament release rate at three hours after the start of test is 60-90% by mass.  
     
     
         5 . The plaster according to  claim 1 , wherein the blending proportion of the styrene-isoprene-styrene block copolymer is 10-30% by mass.  
     
     
         6 . The plaster according to  claim 1 , wherein the average molecular weight of the high molecular weight polyisobutylene is 50,000-200,000 and the blending proportion of the high molecular weight polyisobutylene is 3.6-12% by mass.  
     
     
         7 . The plaster according to  claim 1 , wherein the average molecular weight of the low molecular weight polyisobutylene is 5,000-15,000 and the blending proportion of the low molecular weight polyisobutylene is 2-15% by mass.  
     
     
         8 . The plaster according to  claim 1 , wherein the tackifier is a rosin-based resin and the blending proportion of the tackifier is 5-30% by mass.  
     
     
         9 . The plaster according to  claim 1 , wherein the plasticizer is liquid paraffin and the blending proportion of the plasticizer is 30-60% by mass.  
     
     
         10 . The plaster according to  claim 1 , wherein the dispersant is a metal salt of stearic acid and the blending proportion of the dispersant is 0.1-5% by mass.  
     
     
         11 . The plaster according to  claim 1 , wherein the plaster is further provided with a backing, and the backing has a load at 30%-elongation of 100-800 g in the longitudinal direction and a load at 30%-elongation of 500-2500 g in the lateral direction, as well as has a recovery factor at 50%-elongation of 75-95% in the longitudinal direction and a recovery factor at 50%-elongation of 65-85% in the lateral direction, as prescribed in JIS L 1096 under such measurement conditions that the sample width is 50 mm, the sample length is 200 mm, and the elongation speed is 200 mm/min.