Endocrine, nutritional, and metabolic diseases (E00-E90).
- Diabetes mellitus (diabetes).
- Hypercalcemic crisis – acute condition associated with hyperparathyroidism (parathyroid hyperfunction) with severely elevated blood calcium levels.
Psyche – Nervous System (F00-F99; G00-G99).
- Psychogenic polydipsia (pathologically increased sense of thirst).
Medication
- Abuse of diuretics (dehydrating agents).
