If you buy a nice piece of organic ginger, it should help the gas subside somewhat. I had painful gas trapped inside yesterday, and I made the morning flush drink, and it was gone in a matter of minutes. Really easy:
one cup distilled water
enough citrus to fill blender to 2 cups. i use half a lemon, some orange wedges, and some peeled grapefruit wedges to reduce bitterness
one inch chunk of peeled ginger
3 tbsp of org olive oil
3 cloves garlic
That's my version of the Liver Flush morning drink recipe, but you could always omit the garlic if you're just trying to help gas. Maybe have some extra garlic in some salsa later on ;)