True about Anion Gap:

The cation normally measured is Na+, and the anions are usually Cl- and HCO3-. The "anion gap" is the difference between unmeasured anions and unmeasured cations and is estimated as Normal range: 8-16 mEq/L Increase in chloride ion will decrease anion gap Increased Anion Gap (Normochloremia) Normal Anion Gap (Hyperchloremia) Diabetes mellitus ketoacidosis) Diarrhea Lactic acidosis Renal tubular acidosis Chronic renal failure Carbonic anhydrase inhibitors Aspirin (acetylsalicyclic acid) poisoning Addison's disease Methanol poisoning Ethylene glycol poisoning Starvation