IBS Secondary to PTSD

Overview

Irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction: recurrent abdominal pain tied to bowel movements, with diarrhea, constipation, or both. If your PTSD is service connected, IBS can be service connected on a secondary basis under 38 CFR 3.310 when a medical opinion shows PTSD caused it or made it worse.

The VA rates IBS under Diagnostic Code 7319 at 10%, 20%, or 30%, based on how many days you had abdominal pain related to defecation over the previous three months. IBS is rated in the digestive system, separately from PTSD’s mental-health rating, so a granted IBS rating combines with your PTSD rating.

What the Research Shows About PTSD and IBS

• A consistent association in veterans. A 2019 meta-analysis (Ng et al., Journal of Gastroenterology and Hepatology) pooled eight studies with 648,375 participants, most of them U.S. veterans. PTSD was associated with about 2.8 times the odds of IBS (pooled OR 2.80).
• Trauma and functional syndromes. A 2014 meta-analysis (Afari et al., Psychosomatic Medicine) found people reporting trauma were about 2.7 times more likely to have a functional somatic syndrome such as IBS. The association was larger for PTSD than for other trauma measures.
• Limits of the evidence. Half the studies in the Ng review were cross-sectional, which shows an association but not which condition came first. That is why the timeline in your own records (PTSD symptoms and treatment first, GI complaints later or worsening afterward) carries so much weight.

Proposed mechanisms. Researchers attribute the link to the brain-gut axis. Chronic stress signaling through the autonomic nervous system and the HPA (stress-hormone) axis can alter gut motility and increase gut pain sensitivity (visceral hypersensitivity). These are explanatory models. You do not have to prove a mechanism; a clinician applies the evidence to your history.

Medication pathway. SSRIs and SNRIs used for PTSD (sertraline, paroxetine, venlafaxine) commonly cause nausea and diarrhea, especially when started or when the dose changes. If bowel symptoms began or worsened after a PTSD medication was started, record the dates. A condition caused by treatment for a service-connected disability can be service connected on a secondary basis.

How VA Decides a Secondary IBS Claim

• Causation, 38 CFR 3.310(a): IBS that is “proximately due to or the result of” service-connected PTSD is service connected.
• Aggravation, 38 CFR 3.310(b): If IBS existed first, VA compensates only the worsening caused by PTSD. It will concede aggravation only if medical evidence establishes the baseline severity before the worsening, or the earliest severity after it. It then subtracts the baseline and any natural progression.
• Both questions must be answered. An examiner who says IBS is “not caused by” PTSD has not addressed aggravation. The Court of Appeals for Veterans Claims held in El-Amin v. Shinseki, 26 Vet. App. 136 (2013), that such an opinion is inadequate. If you get a negative opinion that skips aggravation, raise it in a Higher-Level Review or Supplemental Claim.
• Gulf War veterans: functional GI disorders including IBS can be presumptively service connected under 38 CFR 3.317 for qualifying Southwest Asia service, with no nexus required.

Evidence Requirements

• Current IBS diagnosis. A clinician’s diagnosis, usually based on Rome IV symptom criteria after ruling out other causes such as celiac disease, inflammatory bowel disease, or infection.
• Service-connected PTSD. Your rating decision showing PTSD is service connected.
• A medical opinion that addresses causation and aggravation separately. It should use the “at least as likely as not” standard, reflect a review of your records, and explain its reasoning.
• A timeline. Records showing when PTSD symptoms and treatment began and when GI complaints first appear. If IBS came first, the earliest GI records set the baseline.
• Medication history. PTSD medications with start dates and dose changes.
• Symptom diary. Log each day of defecation-related abdominal pain and which of the six DC 7319 features you had. This is the evidence the rating formula uses.
• Lay statements. Family or coworkers can describe observable effects such as urgent bathroom trips, cancelled plans, or diet restrictions.

Rating Criteria

IBS is rated under DC 7319, Irritable bowel syndrome (IBS), in 38 CFR § 4.114. The VA replaced the older “irritable colon syndrome” criteria (mild, moderate, severe) in its digestive system update effective May 19, 2024. The current criteria are based on how often you have abdominal pain related to defecation during the previous three months, plus two or more of: (1) change in stool frequency, (2) change in stool form, (3) altered stool passage (straining and/or urgency), (4) mucorrhea, (5) abdominal bloating, or (6) subjective distension.

10% Rating

Abdominal pain related to defecation at least once during the previous three months, plus two or more of the listed features.

Monthly compensation at 10% (single veteran, no dependents, 2026): $180.42

20% Rating

Abdominal pain related to defecation for at least three days per month during the previous three months, plus two or more of the listed features.

Monthly compensation at 20% (single veteran, no dependents, 2026): $356.66

30% Rating

Abdominal pain related to defecation at least one day per week during the previous three months, plus two or more of the listed features. This is the maximum schedular rating for IBS.

Monthly compensation at 30% (single veteran, no dependents, 2026): $552.47

Important Notes on Rating

• DC 7319 has no 0% level of its own. If your IBS is service connected but does not meet the 10% criteria, the VA assigns 0% under 38 CFR § 4.31.
• Ratings under DC 7301 through 7329 and several other intestinal codes cannot be combined with each other (4.114 preamble). VA assigns one rating for the predominant condition instead. GERD (DC 7206) is not on that list.
• IBS is a physical condition rated in the digestive system. It does not overlap with the PTSD rating under the mental disorders formula, so the two ratings combine.

See our IBS rating guide for more detail.

C&P Exam Tips

The examiner completes an intestinal conditions exam. The rating questions focus on how often you had defecation-related abdominal pain in the last three months and which associated features you had.

• Answer in days. “About three days a month since spring” maps to the criteria. “All the time” does not.
• Name each feature you have. Stool frequency change, stool form change, straining or urgency, mucus, bloating, and distension each count toward the “two or more” requirement.
• Describe the pattern honestly. If flares follow nightmares, triggers, or high-stress periods, say so and give examples. Do not overstate; the examiner compares your account with your records.
• Bring your diary and medication list. Include when GI symptoms started relative to PTSD treatment.
• Mention work and travel effects. They are not part of the DC 7319 formula, but they matter for extraschedular consideration and TDIU.

For general preparation, see our C&P exam guide.

Medical Opinion (Nexus) Tips

Any qualified clinician can write a private opinion. VA weighs it by its reasoning, not the author’s title alone. A treating gastroenterologist, primary care provider, or mental health provider who knows your history is a good choice. A persuasive opinion:

• States whether IBS is “at least as likely as not” caused by service-connected PTSD, and separately whether it is aggravated by PTSD beyond its natural progress
• Shows the clinician reviewed your records and describes your timeline
• Explains the reasoning and cites literature such as the Ng meta-analysis
• Addresses other possible causes (post-infectious IBS, diet, other medications)
• For aggravation, identifies the baseline severity and how it changed

Opinions that say only “may be related” carry little weight because they are speculative.

Impact on Combined Rating

VA combines ratings with the 38 CFR 4.25 combined ratings table. Each step uses the table value, and only the final value is rounded to the nearest 10%.

Example 1: PTSD 70% + IBS 10%

1. 70% combined with 10% = 73
2. 73 rounds to 70%, so there is no change on its own

Example 2: PTSD 70% + tinnitus 10% + IBS 10%

1. 70% combined with 10% = 73
2. 73 combined with 10% = 76
3. 76 rounds to 80%

Example 3: PTSD 70% + IBS 30%

1. 70% combined with 30% = 79
2. 79 rounds to 80%

Use our VA disability calculator to check your own numbers, or see how VA math works.

For personalized guidance on your VA disability claim, consult a VA-accredited VSO, attorney, or claims agent.