The antihypertensives can give you hypotension. Cimetidine can cause some problems, and so can the drugs of abuse. But the drugs you use, the medications you use, you should know everything about them. For example, some of the newer information on the cytochrome P-450 system, in particular the enzymes that break down Prozac, also break down antiarrhythmics, codeine preps, Seldane and Hismanol. So some of the serotonin specific re-uptake inhibitors, like Prozac and Zoloft, can actually elevate drug levels of other medications that we use commonly.
Neurons are particularly sensitive to hyponatremia.
You see that commonly in confusion and delirium, with hyponatremic patients and any head trauma.