113 Pain and Fatigue Syndromes with Bidirectional Causality

Purpose. Recognize pain and fatigue syndromes that both mimic and drive psychiatric symptoms. Avoid reducing complex presentations to primary psychiatric labels.

113.1 Hallmark Signs

Chronic pain or fatigue predates mood/anxiety changes.
Flare patterns tied to stress, sleep, or activity.
Somatic distress dominates clinical presentation.

113.2 High-Risk Contexts

Long-term pain conditions, post-infectious fatigue, fibromyalgia.
High functional impairment with mixed symptom clusters.

113.3 Minimum Workup (by setting)

Basic medical evaluation and review of prior workups. [E0/U2]
Clarify bidirectional impacts on mood, sleep, and cognition.

Red flags

Sudden worsening, neurologic red flags, or severe functional decline. [E0/U3]

Documentation Output. “Pain/fatigue contribution suspected/probable.” Summary of bidirectional effects and monitoring plan.