Drotaverine:

• A Direct smooth muscle spasmolytic agent inhibiting phospho diesterase IV enzyme effectively change membrane prtential and permeability of smooth muscles
• Combination achieves better relief than monotherapy
• Least reported adverse effects

Mefenamic Acid:

• Binds the prostaglandin synthetase receptors COX-I and COX-II
• Inhibiting the acting of prostaglandin sythetase
• Rapidly absorbed after oral administration