A client with bipolar disorder has been taking lithium carbo… | MyMerci
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Adverse Effects/Contraindications/InteractionsPPT
Question
A client with bipolar disorder has been taking lithium carbonate 600 mg orally three times daily for 3 weeks. During a follow-up visit the client reports new symptoms. Which finding is most concerning and warrants immediate provider notification?
1Fine hand tremor on awakening
21 kg weight gain over 2 weeks
3Coarse hand tremor, slurred speech, and ataxia✓ Correct answer
4Increased thirst and urination
Explanation
Lithium has a narrow therapeutic index (0.6 to 1.2 mEq/L). Coarse tremor, dysarthria (slurred speech), and ataxia indicate moderate to severe toxicity (level above 1.5 mEq/L) and require immediate hold, lithium level draw, and provider notification. Polyuria and polydipsia, fine tremor on awakening, and mild weight gain are common expected side effects at therapeutic levels.
KR vs US Therapeutic range and toxicity thresholds match worldwide. Korean psychiatric outpatients also draw quarterly lithium levels and check renal/thyroid function every 6 months.
Clinical scenario
Clinical Practice Guide APA bipolar disorder guidelines list lithium as first-line for maintenance and acute mania. Therapeutic range: 0.6-1.2 mEq/L (acute mania up to 1.5). Toxicity stages: mild 1.5-2.0 (coarse tremor, GI), moderate 2.0-2.5 (ataxia, dysarthria, confusion), severe >2.5 (seizure, coma, death). Hemodialysis indicated if level >4 or symptomatic at >2.5.
Caution Dehydration, low sodium intake, NSAIDs, ACE inhibitors, and thiazide diuretics raise lithium levels. Counsel clients to maintain consistent fluid and salt intake and to avoid OTC NSAIDs without consultation.
Key concepts
Lithium carbonate — First-line mood stabilizer for bipolar disorder. Narrow therapeutic index 0.6-1.2 mEq/L. Excreted unchanged by kidneys; renal function and serum levels checked every 3-6 months. Held before procedures with anticipated dehydration.
Lithium toxicity — Mild (1.5-2.0): coarse tremor, GI distress, polyuria. Moderate (2.0-2.5): ataxia, slurred speech, confusion, muscle twitching. Severe (>2.5): seizure, coma, cardiovascular collapse. Hemodialysis for severe toxicity.
Narrow therapeutic index — Drugs where toxic dose is close to therapeutic dose. Examples: lithium, warfarin, digoxin, theophylline, phenytoin, vancomycin. Require routine serum level monitoring and patient education on symptom recognition.