Functional somatic disorders (FSDs) — think irritable bowel syndrome, chronic fatigue, and hyperventilation — are defined by persistent physical symptoms that can't be pinned to a clear organic cause. They're far from rare: FSDs account for 30%–40% of consultations across medical specialties, with roughly 75% of patients being women and a median onset around age 40. Experts presenting at the 2026 National Days of General Medicine in Paris shed light on how these disorders develop and, crucially, how to treat them.

The mechanism is a vicious cycle. A triggering event — which doesn't have to be dramatic; bereavement or emotional neglect can suffice — sets off a process called operant conditioning, where the brain learns to anticipate symptoms even without a real stimulus. This keeps the sympathetic nervous system on high alert, producing real physical symptoms like tachycardia, shortness of breath, and diarrhea. Patients then avoid activities and seek repeated consultations, which only deepens the cycle.

Key Takeaways:

• First priority in treatment: restore sleep
• Discourage "medical nomadism" (repeated consultations with multiple providers)
• Use graded activity resumption and "micro choices" to tackle avoidance behaviors
• Remove body-monitoring devices (smartwatches, pulse oximeters) to reduce hypervigilance
• CBT supports recovery; medication may help specific symptoms but isn't sufficient alone

Why it matters: FSDs are among the most common — and most undertreated — conditions in clinical practice. Equipping primary care physicians and specialists with a clear framework for diagnosis and management could meaningfully reduce patient suffering and unnecessary healthcare utilization.