MajorLoop diuretics×Psycholeptics. Lithium
Updated · Methodology
Mechanism
Furosemide (loop diuretic) lowers circulating volume and, via subclinical volume depletion, increases lithium reabsorption in the proximal tubules. Serum lithium rises by 25–40%.
Symptoms
Tremor, muscle twitching, nausea, diarrhoea, confusion, ataxia. Severe cases include seizures, coma, and nephrogenic diabetes insipidus with dehydration. Symptoms emerge when serum lithium exceeds 1.2 mmol/L.
Management
Reduce lithium dose by 25–30% when starting or escalating furosemide; check serum lithium at 1 week, then monthly. Maintain normal sodium and fluid balance: deficits worsen lithium toxicity.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →
Sources
- FDA: Lithium carbonate prescribing information (2022)– ; DailyMed setid b839ff4b-f62d-41ab-a823-550a756d58ec
- AEMPS: Ficha técnica: Litio (nº registro 48932), sección 4.5 (2025)– AEMPS, CIMA, nº registro 48932, revisión 04/2025, sección 4.5
- AEMPS: Ficha técnica: Furosemida (nº registro 68077), sección 4.5 (2024)– AEMPS, CIMA, nº registro 68077, revisión 09/2024, sección 4.5