CQAIMH - center for quality assessment and improvement in mental health



Bipolar Disorder: Monitoring lithium serum levels


This measure assesses the percentage of patients diagnosed with bipolar disorder and treated with lithium who have evidence of a lithium serum medication level within 12 weeks of beginning treatment.

Clinical Rationale:

Side Effects of Lithium

  • Up to 75% of patients on lithium experience some side effects, but most are minor (polyuria; polydipsia, weight gain, cognitive problems, sedation or lethargy) and can be reduced or eliminated by dose adjustment or dosage schedule (1)
  • Tremor affects up to 65% of patients treated with lithium and a severe tremor may be a sign of toxicity.  Nausea and diarrhea or blurred vision may also be side effects of toxicity (1,2)

Lithium Levels

  • Target lithium levels are generally 0.8-1.1 mmol/L (3)  
  • Serum concentrations of 0.5 to 1.2 meq/L may be therapeutic according to individual patient response and side effects (1)
  • Patients can experience toxic effects with levels above 1.5 meq/L such as marked tremor, nausea and diarrhea, or blurred vision; levels above 2.0 meq/L are have been associated with life-threatening side effects, such as neurotoxicity, delirium and encephalopathy (1,2)

Monitoring of Serum Lithium Levels

  • Lithium level monitoring is required due to the medication’s narrow therapeutic index (1,2)
  • Check lithium level after initial dosage and after each dosage increase (1)
  • It is recommended to obtain serum levels approximately 5 days after a dosage adjustment as this is when the steady state is reached (1,3)
  • Long-term monitoring recommendations are to check every 3-6 months in patients with stable lithium levels and whenever the clinical status changes (1,3)

Denominator Population:

Patients diagnosed and treated for bipolar disorder with a lithium agent

Data Sources:

  • Administrative data
  • Medical Record

Numerator Population:

Patients with a serum medication level within 12 weeks of beginning treatment with lithium

Data Source:

  • Medical Record

Initial Case-finding Guidance:

Patients with a diagnosis involving bipolar disorder
ICD9CM or DSM IV TR: 296.0x; 296.1x; 296.4x; 296.5x; 296.6x; 296.7; 296.80-82; 296.89; or 301.13


  1. Practice Guideline for the Treatment of Patients with Bipolar Disorder (2002 Revision);  American Psychiatric Association; Am J Psychiatry 159:4, April 2002 Supplement
  2. Freeman M, Freeman S, Lithium: Clinical Considerations in Internal Medicine, The American Journal of Medicine (2006) 119, 478-481
  3. Yatham LN, Kennedy, SH, et al.; Canadian Network for Mood and Anxiety Treatments (CANMAT) guidelines for the managements of patients with bipolar disorder: consensus and controversies, Bipolar Disorders 2005: 7(Suppl. 3): 5-69

Copyright 2007 by the Center for Quality Assessment and Improvement in Mental Health