- Subjects who receive any medication given for the purpose of raising serum sodium while undergoing qualifying serum sodium assessments. Specifically: Hypertonic saline (including normal saline challenge) within 8 hours before each qualifying serum sodium screening assessment; Urea, lithium, demeclocycline, conivaptan, or tolvaptan within 4 days of each qualifying serum sodium screening assessment; Loop diuretics (eg. furosemide, bumetanide, torsemide) within 48 hours of each qualifying serum sodium screening assessment; Other treatment (including normal saline or oral sodium containing supplements) for the purpose of increasing serum sodium within 24 hours of each qualifying serum sodium screening assessment. Final determination will be made in consultation with the sponsor.