Can mebeverine be taken when needed instead of 3x a day as my stomach has settled to what it was?

Depends: Medications such as mebeverine (Colofac, not available in U.S.) that treat spasm of the colon are used for treatment of irritable bowel syndrome, which although not a serious condition, certainly can feel like one.The decision to stop or continue it depends on one's clinical situation & should be discussed with the prescriber. For long-term symptoms, symptoms are likely to return if it is stopped.

Taking it 3 times: per day regularly will work better than sporadic use. However if you are no longer having any symptoms you may not need to be taking this medication any longer. Discuss this with your primary doctor.