This really might explain your mothers behavior as her electrolyte balance was obviously out of kilter....but they need to find out why...if its her diet which from what you've said is most likely the cause....or something else. And then she needs to know she must balance her intake of foods and water....make sense?
Sodium: Sodium is the major positive ion (cation) in fluid outside of cells. The chemical notation for sodium is Na+. When combined with chloride, the resulting substance is table salt. Excess sodium (such as from fast food hamburger and fries) is excreted in the urine. Sodium regulates the total amount of water in the body and the transmission of sodium into and out of individual cells also plays a role in critical body functions. Many processes in the body, especially in the brain, nervous system, and muscles, require electrical signals for communication. The movement of sodium is critical in generation of these electrical signals. Too much or too little sodium therefore can cause cells to malfunction, and extremes (too much or too little) can be fatal. A Normal blood sodium level is 135 - 145 milliEquivalents/liter (mEq/L), or in international units, 135 - 145 millimoles/liter (mmol/L).
Pat