Bobert, I have had IBS for the past 35 years. It is caused by stress.
Avoid all grease and heavily spiced foods.
Have your Doctor prescribe Librax. It was given to me many years ago by a Gastroenterologist and it has worked for me ever since. Whenever I experience severe attacks, I take 2 capsules in the morning and 2 capsules again before bedtime. The symptoms will subside within a week. The generic name for this drug is Clindinium Chlordiazepoxide.