No. Unfortunately, that source is
quite out of date. It's from 2000, and multiple updates to EEOC and ADA guidelines have come out since. As of 2009, IBS would qualify.
"If a person's IBS symptoms significantly impact on a major life ability, IBS would qualify as a covered disability. An amendment to the ADA went into effect on January 1, 2009, that expanded the definition of a disability, providing better protection for individuals with chronic illnesses, such as IBS. Two specific changes are most applicable to IBS:2
Fact Sheet on the EEOC’s Final Regulations Implementing the ADAAA. EEOC Home Page.
- The term "major life activities" now includes recognition of problems with "major bodily functions" such as those of the digestive system.
- The episodic nature of some disabilities is now recognized, as long as the symptoms interfere with a major life activity when present."