Friday, July 24, 2009

Treat Lithium Poisoning

Lithium is an element that is commonly used to treat bipolar disorders and depression. This group has a high risk of overdose, especially because the therapeutic index for lithium is relatively narrow. The dosage must be closely monitored in patients with renal insufficiency because lithium clears the body primarily through the kidneys.








Instructions


1. Observe the signs of lithium toxicity. Mild lithium poisoning is marked by general weakness and mild confusion with resting tremors. Moderate cases will be characterized by more pronounced tremors and muscle twitches and stupor. Severe cases of lithium intoxication can result in seizures, coma and cardiovascular collapse.


2. Measure the serum level to determine the severity of lithium intoxication. The therapeutic dose of lithium is 300/2700 mg/d, with a desired serum level of 0.7 to 1.2 mEq/L. Concentrations above this level may be considered lithium poisoning.


3. Provide gastric decontamination. Gastric lavage is helpful if it is performed within one hour of ingestion. Activated charcoal is not effective in lithium absorption and is only appropriate only if co-ingestion of another poison is suspected.


4. Administer sodium polystyrene sulfonate (Kayexalate). This drug can bind lithium and may enhance elimination, although hypokalemia is a significant side effect.


5. Enhance elimination of lithium from the body. Acute ingestion of timed-release lithium may require whole bowel elimination. Hemodialysis is generally appropriate for patients with concentrations higher than 4 mEq/L, although unstable patients may require dialysis with levels as low as 2.5 mEq/L. Use the patient's mental status to help determine the need for dialysis.

Tags: lithium intoxication, patients with, serum level