A syndrome refers to a collection of symptoms and signs of disordered function of organs associated with one another. Irritable bowel syndrome is a motility disorder involving the entire gastrointestinal tract, causing recurring upper and lower GI symptoms, including variable degrees of abdominal pain, constipation or diarrhea or both, and abdominal bloating.

The cause is unknown. However, emotions, diet, drugs and hormonal factors may give rise to or intensify gastrointestinal motility.

Manifestations tend to appear during the 20s and 30s. Symptoms are apt to occur when the person is awake, are prompted by stress or ingestion of food. Characteristics of the condition include pain that is relieved by defecation; change in the consistency and frequency of stools; distended abdomen; mucoid stools; and the sensation that evacuation is not complete after a bowel movement. Patients may also present with other symptoms including, but not limited to, headaches, fibromyalgia, and temporomandibular joint (TMJ) syndrome. Two major types of irritable colon syndrome have been identified. In the constipation-predominant type, constipation is the leading symptom, but bowel habits vary. The diarrhea-predominant type is characterized by diarrhea that occurs instantly upon rising, or during or right after eating.

Diagnosis is primarily based on the presentation of the aforementioned characteristic symptoms (the Rome criteria) and the exclusion of other disorders. The effectiveness of history-taking is an essential part of the diagnostic process. The specific diagnostic tests include the following components:

• Physical examination - including palpation of the abdomen, digital examination, and pelvic examination for women

• Stool examination - for occult blood (3-day series),ova and parasites or stool cultures if the patient has a history of recent travel

• Proctosigmoidoscopy - to visualize the rectum and colon

• Laboratory examinations - including complete blood count (CBC), erythrocyte sedimentation rate (ESR), urinalysis, and thyroid-stimulating hormone (TSH). In addition, abdominal sonogram, barium enema x-ray, and visualization by scope of the upper or lower gastrointestinal tract or both may be indicated if abnormalities have been established by previous cheaper and less invasive tests.

Explanations to the patient regarding the underlying causes of the disorder, and the fact that there is no organic cause are especially important. This helps to establish a foundation for regular bowel function and therapy suited to the individual patient. Therapy is geared to reduce stress and manage dietary intake (e.g., increasing fiber and decreasing gas-producing foods). In addition, antidiarrheal and antispasmodic drugs (anticholinergics) may be used to assist in regulation of bowel function. Finally, antidepressants may be used to relieve abdominal pain and bloating. Aromatic oils, e.g., peppermint oil, are used to relax smooth muscle that causes pain and cramps. Alternative therapy includes psychotherapy, biofeedback and imaginary hypnotherapy.

Although there are no drugs that offer a cure, specific symptoms can be alleviated with antidiarrheal agents or antispasmodics. Chronic use of antidiarrheal agents is discouraged.

• If the Veteran is a former prisoner of war and was interned or detained for not less that 30 days, this disease shall be service connected if manifest to a degree of disability of 10 percent or more at any time after discharge or release from active military, naval, or air service even though there is no record of such disease during service, provided the rebuttable presumption provisions of 38 CFR 3.307 are also satisfied [38 CFR 3.309 .  [Disease subject to presumptive service connection]

• Consider entitlement to service connection under 38 CFR 3.317(a)(2)(b)(3) as a due to undiagnosed illness and medically unexplained chronic multisymptom illnesses occurring in Persian Gulf Veterans. 

• May also be identified as Irritable Bowel Syndrome, Spastic Bowel Syndrome, or simply as Colitis. Do not confuse the terms Spastic Colitis, Mucous or Mucoid Colitis with ulcerative colitis, which is a separate and distinct disease addressed under Diagnostic Code: 7323.

• Ratings under diagnostic codes 7301 to 7329, inclusive, 7331, 7342, and 7345 to 7348 inclusive will not be combined with each other. A single evaluation will be assigned under the diagnostic code which reflects the predominant disability picture, with elevation to the next higher evaluation where the severity of the overall disability warrants such elevation. [38 CR 4.114]

• There are diseases of the digestive system, particularly within the abdomen, which, while differing in the site of pathology, produce a common disability picture characterized in the main by varying degrees of abdominal distress or pain, anemia and disturbances in nutrition. Consequently, certain coexisting diseases in this area, as indicated in the instruction under the title “Diseases of the Digestive System,” do not lend themselves to distinct and separate disability evaluations without violating the fundamental principle relating to pyramiding as outlined in 38 CFR 4.14.  [38 CFR 4.113]