There are several types of electrolytes that you can loose, for different reasons.
The major ones are -
Sodium loss: perspiration, urine, burns
Chloride Loss: vomiting, dehydration, and some diuretic medications
Potassium Loss: vomiting, diarrhea, chronic laxative use, a high sodium intake, some medications, colonic polyps, and through kidney disease
Calcium Loss: poor nutrition, kidney damage, pancreatitis, low levels of magnesium and vitamin D, and disorders that interfere with calcium absorption
Phosphate Loss: impaired kidney function, hypothyroidism, use of some medications especially theophylline, diuretics, and aluminum-containing antacids, poor nutrition, severe alcohol intoxication, diabetic ketoacidosis, and severe burns
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