Furosemide and Lithium interaction
Furosemide and Lithium: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Furosemide label · effective 2026-05-13
Avoid concomitant use with lithium.
• Lithium : Risk of lithium toxicity ( 7.1 )
Lithium Furosemide reduces lithium’s renal clearance and add a high-risk of lithium toxicity.
From the Lithium (Lithium Carbonate) label · effective 2026-06-04
• Diuretics, NSAID, renin-angiotensin system antagonists, or metronidazole may increase lithium serum concentrations.
Drugs Having Clinically Important Interactions with Lithium Table 4: Clinically Important Drug Interactions with Lithium Diuretics Clinical Impact: Diuretic-induced sodium loss may reduce lithium clearance and increase serum lithium concentrations .
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.