From the Guidelines
Lithium therapy in patients with impaired renal function requires careful monitoring and dose adjustments to minimize the risk of nephrotoxicity and optimize treatment outcomes. According to the most recent and highest quality study 1, patients taking lithium should have their GFR, electrolytes, and lithium levels monitored regularly, ideally every 6 months or more frequently if the dose changes or the patient is acutely unwell.
Key Considerations
- Monitor GFR, electrolytes, and lithium levels every 6 months or more frequently if necessary 1
- Avoid using concomitant NSAIDs to minimize the risk of nephrotoxicity 1
- Maintain hydration during intercurrent illness to reduce the risk of kidney damage 1
- Weigh the risk-benefit of lithium therapy in patients with impaired renal function, considering the potential for nephrotoxicity and the need for close monitoring 1 ### Dosing Adjustments
- For patients with normal kidney function, standard lithium dosing (typically 900-1200 mg/day in divided doses) can be used, targeting serum levels of 0.6-1.2 mEq/L
- For patients with reduced kidney function (eGFR <60 mL/min), dose reductions of 25-50% are necessary, with more frequent monitoring (every 1-3 months) 2, 3
- Lithium should be used cautiously or avoided in severe kidney impairment (eGFR <30 mL/min) ### Additional Recommendations
- Single daily dosing is preferred to reduce peak concentrations and kidney stress
- Adequate hydration (2-3 liters daily) and avoiding NSAIDs and diuretics can help protect kidney function
- Lithium affects kidney function by interfering with antidiuretic hormone action, potentially causing nephrogenic diabetes insipidus with polyuria and polydipsia
- If these symptoms develop or if progressive kidney function decline occurs, consider dose reduction or switching to an alternative mood stabilizer 4
From the FDA Drug Label
When kidney function is assessed, for baseline data prior to starting lithium therapy or thereafter, routine urinalysis and other tests may be used to evaluate tubular function (e. g., urine specific gravity or osmolality following a period of water deprivation, or 24-hour urine volume) and glomerular function (e.g., serum creatinine or creatinine clearance). Lithium toxicity is closely related to serum lithium levels, and can occur at doses close to therapeutic levels (see DOSAGE AND ADMINISTRATION). Lithium should generally not be given to patients with significant renal or cardiovascular disease, severe debilitation or dehydration, or sodium depletion, and to patients receiving diuretics, since the risk of lithium toxicity is very high in such patients. If the psychiatric indication is life-threatening, and if such a patient fails to respond to other measures, lithium treatment may be undertaken with extreme caution, including daily serum lithium determinations and adjustment to the usually low doses ordinarily tolerated by these individuals.
The renal adjustments with lithium therapy in patients with impaired renal function are not explicitly stated in the provided drug labels. However, it is recommended to monitor kidney function closely and adjust the dose as needed to avoid lithium toxicity. Patients with significant renal disease should be treated with extreme caution and may require hospitalization [5] [6].
- Key considerations for patients with impaired renal function include: + Monitoring serum lithium levels + Evaluating tubular and glomerular function + Adjusting the dose to prevent lithium toxicity + Considering alternative treatments or hospitalization if necessary.
From the Research
Renal Adjustments with Lithium Therapy
- Lithium treatment is associated with renal side effects, ranging from mild nephrogenic diabetes insipidus to end-stage renal disease (ESRD) 7, 8, 9.
- Long-term lithium treatment can lead to a decline in renal function, with approximately 1% of patients developing ESRD after 15 years of treatment 9.
- The risk of chronic kidney disease is higher in patients treated with lithium compared to those treated with other mood stabilizers, with age, duration of lithium therapy, and medical disorders such as hypertension and diabetes mellitus being risk factors 8.
Monitoring Renal Function
- Regular monitoring of renal function, including estimated glomerular filtration rate (eGFR), is essential for patients taking lithium 8, 10.
- A baseline measure of renal function should be obtained before starting lithium treatment, and eGFR should be monitored regularly during treatment 8.
- If eGFR falls rapidly or below 60 ml/minute, patients should consider consulting a nephrologist 8.
Risk Factors for Renal Damage
- Male sex appears to be a risk factor for the development of kidney damage during long-term lithium treatment 11.
- Duration of lithium therapy is also a risk factor, with longer treatment durations associated with a higher risk of renal damage 7, 8.
- Medical disorders such as hypertension and diabetes mellitus can increase the risk of chronic kidney disease in lithium-treated patients 8.
Management of Lithium-Induced Renal Damage
- Patients with impaired renal function should be closely monitored, and the decision to discontinue lithium should be made using a risk/benefit analysis 8.
- Discontinuation of lithium may not always lead to improvement in renal function, especially in patients with more severe renal damage 8.
- Clinicians should be aware of the potential for lithium toxicity, even in patients taking the prescribed dosage, and monitor renal function regularly to avoid toxicity 10.