You can get VA disability for IBS secondary to PTSD by filing a secondary service connection claim that links your irritable bowel syndrome to your already service-connected PTSD. If the VA grants the claim, IBS is rated at 10, 20, or 30 percent under Diagnostic Code 7319, and that rating combines with your PTSD rating to raise your overall compensation. The claim rises or falls on one thing more than any other: a medical opinion connecting the two conditions.
What You Have to Prove
Under 38 C.F.R. § 3.310, a disability is service-connected on a secondary basis when it is “proximately due to or the result of” a condition that is already service-connected.1eCFR. Secondary Service Connection, 38 CFR 3.310 For IBS tied to PTSD, that translates into three things you have to put in front of the VA:
- A current IBS diagnosis from a medical provider, ideally supported by testing (colonoscopy, imaging, stool studies) that rules out conditions like Crohn’s disease or celiac disease.
- An existing service-connected rating for PTSD, or a PTSD claim filed at the same time as the IBS claim.
- A medical nexus opinion connecting the two.
The biological basis the VA and medical examiners rely on is the gut-brain axis. Chronic hyperarousal from PTSD keeps the hypothalamic-pituitary-adrenal (HPA) axis activated, and that activation alters intestinal motility, increases stomach acid, and produces the diarrhea, constipation, and abdominal pain characteristic of IBS. A 2019 meta-analysis in the Journal of Gastroenterology and Hepatology found that people with PTSD had 2.8 times the odds of developing IBS, with most of the studies drawn from U.S. military veterans.2PubMed. Systematic Review With Meta-Analysis: The Association Between Post-Traumatic Stress Disorder and Irritable Bowel Syndrome VA health data shows veterans with PTSD are 2.73 times more likely to be diagnosed with IBS than the general veteran population.3PMC. Bidirectional Association Between PTSD and Gastrointestinal Diseases in U.S. Military Veterans That literature is what a good nexus opinion draws on.
Causation, Aggravation, and Medication
There are three theories that can carry a secondary claim, and knowing which one fits your situation matters for how you prepare the evidence.
Causation is the straightforward theory: PTSD caused your IBS. The onset of GI symptoms follows the onset or worsening of PTSD, and no other clear cause explains it.
Aggravation is the theory that PTSD made pre-existing or independently developing IBS worse. It is a legally distinct question from causation, and the VA is required to consider it separately under Allen v. Brown, 7 Vet. App. 439 (1995).4Federal Register. Claims Based on Aggravation of a Nonservice-Connected Disability This distinction matters because VA examiners routinely conclude that PTSD did not directly cause IBS while ignoring whether it aggravated the condition. In a March 2025 Board of Veterans’ Appeals decision, the Board granted IBS secondary to PTSD precisely because prior VA examiners had failed to address aggravation, and a private opinion establishing at least a 50 percent probability of aggravation tipped the scale.5VA Board of Veterans’ Appeals. Citation Nr: A25028989 Aggravation claims require establishing a baseline severity of the IBS before the aggravation began, which can come from earlier medical records or the earliest records available after the worsening. The VA then compensates for the incremental worsening rather than the full severity.1eCFR. Secondary Service Connection, 38 CFR 3.310
The medication pathway is a third option. Antidepressants and antipsychotics commonly prescribed for PTSD have known GI side effects. In a January 2020 BVA decision, the Board granted IBS secondary to PTSD based on evidence that PTSD medications were causing the symptoms, supported by an examiner’s opinion and treatment records showing improvement after a medication change.6VA Board of Veterans’ Appeals. Citation Nr: A20000208 Pharmacy records and the patient information leaflet for the medication can support this theory.7CCK Law. VA Disability for Medication Side Effects
The Nexus Letter
The nexus letter is the single most decisive piece of evidence in these claims, and a weak or vague one is the most common reason they are denied.8VA Board of Veterans’ Appeals. Citation Nr: 1142049 A useful nexus letter has four features.
It uses the standard “at least as likely as not” (a 50 percent or greater probability). Softer language like “possibly related” or “could be connected” does not meet the VA’s evidentiary threshold.
It explains the physiological mechanism, typically the gut-brain axis and HPA-axis disruption, and it cites the medical literature. Opinions that reference the peer-reviewed studies on PTSD and IBS carry more weight than bare assertions.9VA Board of Veterans’ Appeals. Citation Nr: A23035432
It addresses causation and aggravation as separate questions. Under Atencio v. O’Rourke, 30 Vet. App. 74 (2018), an opinion that only addresses causation is legally inadequate.5VA Board of Veterans’ Appeals. Citation Nr: A25028989 The same standard applies to VA C&P examiner opinions, which is one of the most useful grounds for challenging a negative examination on appeal.
It considers other potential contributors like diet, alcohol use, and other medical conditions. Opinions that ignore these variables are easier for the VA to outweigh.
Lay statements from you and your spouse describing how IBS symptoms flare during PTSD symptom flare-ups add real value for showing the pattern, but they do not substitute for the medical opinion, which must come from a qualified professional.
How the VA Rates IBS
IBS is rated under Diagnostic Code 7319. The VA updated the digestive-system rating criteria effective May 19, 2024, shifting the IBS standard to a symptom-frequency framework measured over three months.10VA News. VA Updates Disability Rating Schedule for Digestive System To qualify for any rating, you need abdominal pain related to defecation plus at least two of six secondary symptoms: changes in stool frequency, changes in stool form, altered stool passage (straining or urgency), mucorrhea, abdominal bloating, or subjective distension.11eCFR. 38 CFR 4.114, Diagnostic Code 7319
The three rating levels are:
- 10 percent: abdominal pain related to defecation at least once during the previous three months, plus two or more secondary symptoms.
- 20 percent: abdominal pain related to defecation at least three days per month during the previous three months, plus two or more secondary symptoms.
- 30 percent: abdominal pain related to defecation at least one day per week during the previous three months, plus two or more secondary symptoms. This is the maximum schedular rating.
Because the criteria depend on symptom frequency over a defined window, a written symptom log covering the twelve weeks before your C&P exam is one of the most practical things you can do. Track dates of episodes, whether pain was tied to defecation, and which secondary symptoms occurred. The VA’s Intestinal Conditions Disability Benefits Questionnaire asks the examiner to report pain frequency in terms of “at least once,” “at least 3 days per month,” or “at least 1 day per week,” so a log built around those exact thresholds gives the examiner something concrete to check.12VA Benefits. Intestinal Conditions Disability Benefits Questionnaire
If you already had an IBS rating before May 19, 2024, the VA will not reduce it solely because the criteria changed. For claims pending on that date, the VA evaluates the claim under both the old and new criteria and applies whichever result is more favorable.10VA News. VA Updates Disability Rating Schedule for Digestive System
What IBS Adds to Your Existing PTSD Rating
A secondary IBS rating combines with your PTSD rating through the VA’s combined ratings table rather than by simple addition. Each new disability reduces your remaining functional capacity by its own percentage. A veteran rated 70 percent for PTSD has 30 percent remaining capacity; a 30 percent IBS rating reduces that remaining capacity by 30 percent, which is 9 percentage points, for a combined value of 79 percent that rounds to 80 percent.13VA. About VA Disability Ratings
The dollar difference matters. As of 2026, a single veteran with no dependents receives $1,808.45 per month at 70 percent and $2,102.15 at 80 percent.14CCK Law. VA Disability Calculator
Secondary IBS also counts toward Total Disability based on Individual Unemployability. Under 38 C.F.R. § 4.16(a), schedular TDIU requires two or more service-connected disabilities with at least one rated 40 percent or higher and a combined rating of at least 70 percent. Adding IBS to an existing PTSD rating can push a veteran across the 70 percent combined line.15VA Board of Veterans’ Appeals. Citation Nr: A25023612
When Other GI Conditions Are Also in Play
Veterans with PTSD often develop more than one GI condition. GERD, peptic ulcer disease, functional dyspepsia, and diverticular disease have all been linked to PTSD in veteran populations.3PMC. Bidirectional Association Between PTSD and Gastrointestinal Diseases in U.S. Military Veterans You can file secondary claims for more than one of them, but the rating schedule limits how they combine. Under 38 C.F.R. § 4.114, ratings under Diagnostic Codes 7301 through 7329 (which includes IBS at DC 7319) cannot be combined with each other. Instead, the VA assigns a single rating under whichever code reflects the predominant disability, elevating it one level if the overall severity warrants.16eCFR. 38 CFR 4.114, Rating Rules for Digestive Conditions
Conditions rated outside that range, such as GERD under DC 7206 in the 7200 series, can potentially be rated separately from IBS under the VA’s 2024 final rule, as long as the symptoms do not overlap.17Federal Register. Schedule for Rating Disabilities: The Digestive System In practice the VA often treats IBS and GERD symptoms as overlapping and assigns one rating.
The Gulf War Alternative
If you served in the Southwest Asia theater of operations on or after August 2, 1990, IBS is a presumptive condition for you, meaning the VA presumes it is connected to service without your having to prove a nexus.18VA. Gulf War Illness Presumptive Conditions The condition must be at least 10 percent disabling and must have appeared during active duty or afterward.19VA Public Health. Gulf War Presumptive Conditions If you qualify for both, you can pursue the presumptive theory and a secondary-to-PTSD theory at the same time, which protects the claim if the VA disputes one of them.
Filing the Claim and the C&P Exam
You file the claim on VA Form 21-526EZ, the same form used for all disability compensation claims. It can be submitted online through VA.gov, by mail, or in person at a VA regional office. Filing a fully developed claim with the diagnosis, nexus letter, and symptom log already in the file speeds the decision and gives the C&P examiner the strongest possible picture. The VA’s average processing time as of February 2026 was 76.7 days.20VA. How to File a VA Disability Claim
The C&P examination for IBS is usually 15 to 20 minutes. The examiner uses the Intestinal Conditions Disability Benefits Questionnaire, updated in July 2024, and evaluates your symptoms against the DC 7319 thresholds.12VA Benefits. Intestinal Conditions Disability Benefits Questionnaire Be ready to describe how often you had abdominal pain related to defecation in the last three months and which secondary symptoms you had.
If the C&P examiner writes a negative opinion, look at whether it addressed aggravation as a separate question from causation and whether it provided a real rationale grounded in the medical literature. Both of those inadequacies are recurring reasons the Board of Veterans’ Appeals has overturned negative decisions and granted service connection for IBS secondary to PTSD.5VA Board of Veterans’ Appeals. Citation Nr: A25028989