Drug interactions
Chlorothiazide + Lithium
Severity: Major
Chlorothiazide and Lithium: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Thiazide diuretics reduce renal lithium clearance and can raise serum lithium, leading to toxicity with tremor, confusion, vomiting and ataxia.
What this interaction means in plain words
Chlorothiazide and Lithium can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Chlorothiazide belongs to Cardiovascular; Lithium belongs to Central Nervous System.
Why it happens
Thiazide-induced sodium depletion increases proximal tubular reabsorption of lithium.
What to do
Avoid if possible. If used, reduce the lithium dose and monitor serum lithium closely after starting, with attention to sodium and renal function.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Lithium
- Lithium + Thioridazine Contraindicated
- Lithium + Vandetanib Contraindicated
- Aceclofenac + Lithium Major
- Acemetacin + Lithium Major
- Amisulpride + Lithium Major
- Amlodipine-benazepril + Lithium Major
Other interactions of Chlorothiazide
Frequently asked questions
Can I take Chlorothiazide with Lithium?
MediHelp rates the interaction as major. Chlorothiazide and Lithium can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Thiazide diuretics reduce renal lithium clearance and can raise serum lithium, leading to toxicity with tremor, confusion, vomiting and ataxia.
How serious is the interaction between Chlorothiazide and Lithium?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid if possible. If used, reduce the lithium dose and monitor serum lithium closely after starting, with attention to sodium and renal function.
What other medicines interact with Lithium?
MediHelp also lists interactions of Lithium with, for example, Thioridazine, Vandetanib, Aceclofenac. The full list is on the Lithium page.
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