Irritable Bowel Syndrome (IBS)

DC 7319 §4.114 Digestive ICD-10: K58.9 DirectPresumptiveSecondary Gulf War undiagnosed illness (deadline 12/31/2026)

Functional GI disorder. Cannot be combined with GERD. Gulf War undiagnosed illness presumptive.

VA rating criteria

Rating	Criteria
30%	Severe; diarrhea, or alternating diarrhea and constipation, with more or less constant abdominal distress
10%	Moderate; frequent episodes of bowel disturbance with abdominal distress
0%	Mild; disturbances of bowel function with occasional episodes of abdominal distress

Often claimed secondary to

If you're already service-connected for any of these, Irritable Bowel Syndrome (IBS) is often a viable secondary claim.

Post-Traumatic Stress Disorder (PTSD)

Mental health condition from experiencing or witnessing a traumatic event. Stressor verification required (except combat-related, which is presumed if consistent with circumstances of service).

Filing this claim

If you have qualifying service for the Gulf War undiagnosed illness (deadline 12/31/2026) presumption, you don't need a nexus letter — file as a primary claim with proof of qualifying service and your current diagnosis. Use the letter generators to draft your nexus letter and Statement in Support of Claim.

Step by step

File an Intent to File (Form 21-0966) to lock your effective date.
Confirm you have a current medical diagnosis in a medical record.
Gather proof of qualifying service (DD-214, deployment records, etc.) — no nexus letter needed.
Write a Statement in Support of Claim (21-4138).
If applicable, gather buddy statements (21-10210).
File the formal 21-526EZ.

Source: 38 CFR §4.114. For exact regulatory language, consult eCFR Title 38. This is general education — for your specific case, consult a VA-accredited representative.