Management of Functional Abdominal Pain
The most effective approach to managing functional abdominal pain requires a structured treatment strategy based on symptom severity, with first-line therapies including antispasmodics for pain-predominant symptoms and tricyclic antidepressants for more severe or frequent pain. 1
Initial Assessment and Diagnosis
- Functional abdominal pain is characterized by constant or frequently recurring abdominal pain that is not associated with eating, bowel habits, or menstrual periods, distinguishing it from irritable bowel syndrome and other functional GI disorders 2
- During acute episodes, plain abdominal radiography should be performed to exclude bowel obstruction and other abdominal pathology 1
- Additional testing (small bowel series, CT scan) may be needed based on symptom duration, severity, changes in symptom type, and demographic factors 1
Treatment Algorithm Based on Symptom Severity
Mild Symptoms
- Establish an effective therapeutic relationship with validation that symptoms are real 1, 3
- Provide education and reassurance about the nature of functional abdominal pain 1
- Implement dietary and lifestyle modifications as needed 1
- Consider symptom monitoring using a diary to identify potential triggers 1
Moderate Symptoms
- Pharmacological treatment directed at predominant symptoms:
- For pain-predominant symptoms: Antispasmodic (anticholinergic) medications, particularly when symptoms are exacerbated by meals 1, 4
- For diarrhea: Loperamide (2-4 mg, up to four times daily) to reduce loose stools and urgency 1
- For constipation: Increased dietary fiber (25 g/day), although evidence for pain reduction is mixed 1
Severe or Refractory Symptoms
- Tricyclic antidepressants (TCAs) at low doses are the mainstay of therapy for functional pain disorders, with analgesic effects occurring at lower doses than required for mood effects 1, 3
- For patients with psychological comorbidities, consider selective serotonin reuptake inhibitors (SSRIs) at therapeutic doses 1
- For severe pain, consider combination therapy (augmentation) with different neuromodulators, while monitoring for serotonin syndrome 1
- Avoid opioids and benzodiazepines due to high risk of dependence and potential to worsen symptoms long-term 1, 3
Psychological Interventions
- Psychological treatments should be initiated when symptoms are severe enough to impair health-related quality of life 1
- Evidence-based psychological approaches include:
- Cognitive-behavioral therapy (CBT) - most effective for patients with insight into how thoughts, feelings, and behaviors relate to their pain 1, 5
- Gut-directed hypnotherapy - particularly effective for visceral hypersensitivity 1
- Mindfulness-based stress reduction - helpful for managing psychological stress and negative emotions 1
- Psychodynamic interpersonal therapy - beneficial for those with history of abuse or adverse early-life experiences 1
Dietary Approaches
- Standard dietary advice should be provided for patients with mild gastrointestinal symptoms 1
- For moderate to severe symptoms, consider a low FODMAP diet with proper nutritional guidance from a dietitian 1
- For patients with significant psychological comorbidities, a modified "gentle" FODMAP approach may be more appropriate 1
Special Considerations
- Screen all patients for underlying psychiatric disturbances, as untreated mood disorders adversely affect treatment response 3
- Be vigilant for risk factors that may lead to chronicity, including history of chronic pain, early-life adversity, poor coping styles, and pre-existing anxiety or depression 1
- Avoid invasive interventions in patients with functional symptoms, especially those with pain-predominant presentations without objective features of biochemical disturbance 1
- Set realistic expectations with patients that the goal of treatment is to decrease pain and increase function over time, not to cure the disorder 3