Fluoride Toxicity Workup

Updated: Jan 11, 2021
  • Author: Johnathan Ly, MD; Chief Editor: Michael A Miller, MD  more...
  • Print

Approach Considerations

Measurement of serum electrolytes may be indicated in patients with suspected fluoride toxicity to investigate for the following abnormalities:

  • Hyperkalemia
  • Hypocalcemia
  • Hypomagnesemia

Measure fingerstick on all patients with seizure and altered mental status because of the risk for hypoglycemia with systemic fluoride toxicity. Serum and urine fluoride levels are not available for emergency department evaluation.

Electrocardiogram and cardiac monitoring may be indicated for suspected fluoride toxicity. Abnormalities found may reflect the effects of electrolyte imbalances, as follows:

  • Hyperkalemia - Peaked T waves, widened QRS, bradycardia, atrioventricular [AV] nodal blockade
  • Hypocalcemia - Prolonged corrected QT interval (QTc)