Lithium and Metronidazole interaction
Lithium and Metronidazole: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Lithium (Lithium Carbonate) label · effective 2026-06-04
• Diuretics, NSAID, renin-angiotensin system antagonists, or metronidazole may increase lithium serum concentrations.
From the Metronidazole (LIKMEZ) label · effective 2025-04-18
Lithium: Increased lithium serum concentrations; measure serum lithium and serum creatinine concentrations during therapy.
Lithium In patients stabilized on relatively high doses of lithium, short-term use of LIKMEZ has been associated with elevation of serum lithium concentrations and signs of lithium toxicity due to the interaction between metronidazole and lithium.
Monitor serum lithium and serum creatinine concentrations for several days after beginning treatment with LIKMEZ to detect any increase that may precede clinical symptoms of lithium toxicity.
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.