Download for FREE today - special Mnemonics Cheatsheet - so you can be SURE that you have that Must Know information down: bit.ly/nursing-memory Outline SALT LOSS S-Stupor/coma A-Anorexia, N&V L-Lethargy T-Tendon reflexes decreased L-Limp muscles (weakness) O-Orthostatic hypotension S-Seizures/headache S-Stomach cramping Description Hyponatremia is decreased levels of sodium in the blood. It can be caused by inadequate sodium or excess free water which leads to lower concentration of sodium. Sodium and potassium work together to allow depolarization of muscles. Low sodium levels can limit this ability and cause muscle weakness. Sodium in the blood helps maintain the oncotic pressure. If fluid leaves the blood vessels, it can lead to decreased blood pressure.