Serum Lithium Monitoring and Management

Factors Affecting Lithium Levels

• Medications that affect renal function can alter lithium levels, as renal function significantly impacts lithium clearance 1
• Intercurrent illness may require more frequent monitoring due to potential changes in lithium clearance 2
• Lithium should be temporarily discontinued during serious intercurrent illness that increases risk of acute kidney injury 3

Signs of Toxicity Requiring Immediate Testing

• Early signs of lithium toxicity include tremor, nausea, diarrhea, and polyuria-polydipsia 2, 1
• If toxicity is suspected, immediate serum lithium testing is warranted regardless of the regular monitoring schedule 1

Baseline and Ongoing Monitoring

• Before starting lithium, baseline tests should include complete blood count, thyroid function tests, renal function tests, serum calcium, urinalysis, and pregnancy test in females of reproductive age 2
• After stabilization, ongoing monitoring should include renal function tests, thyroid function tests, and urinalysis every 3-6 months, and serum calcium at least annually 2