Lithium Lila — Lithium: Therapeutic Levels, Toxicity & Sodium Balance
Lithium steadies her moods — but it rides on sodium, and one sweaty week or skipped salt can push her into toxicity
Lila's bipolar disorder has been stable on lithium for two years. After a week of food poisoning with vomiting and diarrhea, her hands shake, she feels confused, and her lithium level comes back at 1.9 mEq/L.
Lila takes lithium for bipolar disorder, and lithium has one of the narrowest therapeutic windows in all of nursing: 0.6-1.2 mEq/L for maintenance, with toxicity beginning around 1.5. Because lithium is a salt handled by the kidneys exactly like sodium, anything that depletes sodium or water — sweating, vomiting, diuretics, low-salt diets — makes the kidneys reabsorb more lithium and levels climb. Early toxicity is fine tremor, nausea and diarrhea; severe toxicity is coarse tremor, confusion, seizures and dysrhythmias. NSAIDs and thiazide diuretics raise lithium levels; consistent sodium and fluid intake keeps them steady.
Read Lithium Lila's full story →The story arc
The setup
Lila starts lithium and learns the rules: same salt intake every day, 2-3 liters of water daily, and blood levels drawn regularly.
The turn
After several days of vomiting and diarrhea, Lila develops a fine hand tremor, nausea and mild confusion.
The crisis
Her level returns at 1.9 mEq/L and her tremor becomes coarse; she is increasingly lethargic.
The save
Lithium is held, IV normal saline restores sodium and volume to promote lithium excretion, and her level is rechecked until it returns to range.
NCLEX study section — Lithium: Therapeutic Levels, Toxicity & Sodium Balance
What this chapter is testing: the recognition cues, the numbers and the priority action.
Study section: Pharmacology
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