Metabolic headaches.

This article discusses headaches secondary to disorders of homeostasis, which include headaches attributed to (1) hypoxia and/or hypercapnia (high-altitude, diving, or sleep apnea), (2) dialysis, (3) arterial hypertension (pheochromocytoma, hypertensive crisis without hypertensive encephalopathy, hypertensive encephalopathy, preeclampsia or eclampsia, or autonomic dysreflexia), (4) hypothyroidism, (5) fasting, (6) cardiac cephalalgia, and (7) other disorder of homeostasis. Clinical features and diagnosis as well as therapeutic strategies are discussed for each headache type.