Rapid pain relief using transdermal film forming polymeric solution of ketorolac

Context: Ketorolac is one of the most potent nonsteroidal anti-inflammatory drugs and is an attractive alternative to opioids for pain management. Objective: Development and evaluation of transdermal ketorolac film forming polymeric solution. Materials and methods: Eudragits (R) RLPO, RSPO and E100 as well as polyvinyl pyrrolidone K30 dissolved in ethanol were used as film forming solutions. In vitro experiments were conducted to optimize formulation parameters. Different permeation enhancers were monitored for potentiality of enhancing drug permeation across excised pigskin. Results: The use of 10% oleic acid, Lauroglycol (R) 90 or Azone (R) with 5% Eudragit (R) RSPO, showed the highest enhancement effect on ketorolac skin permeation and showed faster analgesic effect compared to the ketorolac tablet. The formula comprising 5% Eudragit (R) RSPO and 10% Lauroglycol (R) 90 showed the greatest pharmacodynamic effect and thus was subjected to pharmacokinetic studies. The pharmacodynamic and pharmacokinetic results didn't run paralleled to each other, as the ketorolac tablets showed higher plasma concentrations compared to the selected ketorolac transdermal formulation. This might be due to the induction of analgesia by the available ethanol in the transdermal preparation. Conclusion: Optimized transdermal ketorolac formulation showed marked ability to ensure fast and augmented analgesic effect that is an essential request in pain management.