Prediction of the Efficacy of Cutaneously Applied Nonsteroidal Anti-inflammatory Drugs from a Lipophilic Vehicle

The maximum cutaneous fluxes of 12 nonsteroidal anti-inflammatory drugs (NSAIDs), determined in a preceding study from the lipophilic vehicle light mineral oil in vivo on 24 healthy volunteers, were related to data concerning their intrinsic activities. From the multiplication of the relative intrinsic activities with the relative maximum fluxes, both related to indometacin (CAS 53-86-1) as standard, the percutaneous activities result as parameters for the prediction of the efficacy of cutaneous preparations with NSAIDs. According to the results of the calculations, the percutaneous activities of ibuprofen (CAS 15687-27-1) and nabumetone (CAS 42924-53-8) from lipophilic vehicles are remarkable because of their very high maximum fluxes. NSAIDs with still high percutaneous activities are ketoprofen (CAS 22071-15-4), naproxen (CAS 22204-53-1), piroxicam (CAS 36322-90-4) and diclofenac (CAS 15307-86-5). In contrast, the systemically highly effective NSAIDs indometacin and acemetacin (CAS 53164-05-9) show rather low percutaneous activities, when applied in lipophilic vehicles. Especially nabumeton and also tenoxicam (CAS 59804-37-4), both not yet commercially used cutaneously, can be recommended for lipophilic skin preparations.