Abstract
In order to relieve oral mucosal pain topically, we prepared a 2% mefenamic acid (MA) spray using carboxyvinyl polymer (CP, 0.25% and 0.5%) and compared it with a MA spray prepared using sodium polyacrylate (PANa, 0.2%). In the stability and dispersion tests, the MA content of the 0.25% and 0.5% CP sprays had not changed 28 days after preparation under 5 test conditions (4°C without shading, 25°C without shading, 37°C without shading, 4°C with shading, 25°C with shading). However, the MA content of the spray prepared using 0.2% PANa had decreased 3 days after preparation, demonstrating that CP was better as a dispersion agent. When the sprays were used for healthy volunteers, the salivary concentration of MA for the 0.5% CP spray was higher than that achieved with the 0.25% CP spray (0.25% CP : 3.47±1.03 mg, 0.5% CP : 4.98±1.23 mg, P<0.05).
The clinical efficacy was tested in 89 out-patients (age ranging from 18 to 91 years) with eight different diseases exhibiting oral mucosal pain, who received the 0.25% CP spray (n=48) or the 0.5% CP spray (n=41). Sixty-one patients showed an analgesic effect on application of MA spray (0.25% CP : 30 patients, 0.5% CP : 31 patients) and the mean onset of action was 1'58"±1'10" (0.25% CP : 1'56"±1'13", 0.5% CP : 2'01"±1'09").
In the case of hyperesthesia and decubitus ulcer, the analgesic effect was 100% suggesting that regardless of the concentration, MA sprays using CP are very effective in patients with oral mucosal pain other than that due to oral mucostitis.
