Lithium Carbonate and Mate: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Lithium Carbonate
Mate
No brand names on record
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Unexpected changes in serum lithium levels
Interaction Deep Dive
Mate contains 0.2% to 2.0% caffeine, 0.1% to 0.2% theobromine and 0.05% theophylline; its pharmacological actions are attributed to caffeine5. The caffeine content may increase lithium excretion. Dosage adjustments for lithium may need to be made if caffeine content is consistently maintained. Upon discontinuation of caffeine intake or if the patient elects to significantly decrease caffeine intake, the patient may experience lithium toxicity if the lithium dosage is not decreased accordingly.
Why it happens (mechanism)
Since approximately 95% of lithium is renally excreted and since caffeine increases urine formation, it appears that when caffeine consumption is discontinued, less lithium is excreted
Literature reports
4 reports — tap to read
a) Abrupt discontinuation of caffeine intake resulted in a 24% increase in lithium blood levels in a study of 11 patients (10 patients with bipolar disorder; one patient with schizoaffective disorder). These patients (four men and seven women) whose mean age was 42.5 +/- 9.1 years (range: 33 to 65 years) consumed four to eight cups of coffee daily (5.3 +/- 0.7 cups daily) for at least 10 years and had been maintained on lithium (600 to 1200 mg daily) with no other psychotropic drugs. Patients were assessed at baseline (while on regular caffeine consumption), two weeks after a caffeine-free diet, and two weeks after resuming regular caffeine consumption (estimating a quantity of 70 mg to 120 mg caffeine per cup of coffee). Eight of the 11 (73%) patients experienced increases in lithium blood levels upon caffeine discontinuation. At baseline, lithium levels were 0.46 +/- 0.04 milliequivalents/liter (mEq/L) which increased to 0.57 +/- 0.03 mEq/L (p less than 0.05) upon caffeine withdrawal, representing a 24% increase. When caffeine was resumed, lithium levels decreased to 0.45 +/- 0.03 mEq/L (p less than 0.01) 1.
b) Increased lithium levels secondary to caffeine withdrawal has resulted in tremor. A 38-year-old woman had been maintained on lithium 1500 mg daily with serum lithium levels of 1.04, 1.1 and 0.99 millimoles/liter (mmol/L). Because of anxiety and a mild tremor, she agreed to eliminate caffeine from her diet so she abruptly discontinued drinking 17 cups of coffee daily. Within days her tremor was much worse and her lithium level had increased by approximately 50% to 1.52 mmol/L. With dosage reduction to 1200 mg daily, serum lithium level decreased to 1.0 mmol/L and the tremor markedly decreased in intensity 2.
c) A 63-year-old woman with bipolar affective disorder taking 450 mg of controlled-release lithium daily reported mild tremor. She discontinued her coffee intake of four cups to several pots daily. She experienced headache within one day; the headache was gone by the next day. She also experienced an increase in tremor lasting for one month. Tremor resolved when the lithium dose was decreased. Serum lithium levels were not obtained but the symptoms suggest lithium toxicity occurred upon caffeine discontinuation 2.
d) Increase lithium urinary excretion was observed in subjects who ingested caffeine in a single dose, the same as occurred with a one gram dose of another methylxanthine, aminophylline 3. Six subjects who consumed caffeine 800 mg daily did not experience any significant changes in renal lithium clearance 4.
Common questions
Can I take Lithium Carbonate and Mate together?
Unexpected changes in serum lithium levels Always confirm with your pharmacist or prescriber before making any change.
How serious is the Lithium Carbonate and Mate interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "delayed". Effects tend to build up gradually over days to weeks.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Lithium Carbonate or Mate need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there anything you'd monitor while I'm on both?
References (5)
- Mester R, Toren P, Mizrachi I, et al: Caffeine withdrawal increases lithium blood levels. Biol Psychiat 1995; 37:348-350. PubMed
- Jefferson JW: Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988; 49:72-73.
- Thomsen K & Schou M: Renal lithium excretion in men. Am J Physiol 1968; 215:823-827.
- Bikin D, Conrad KA, & Mayersohn M: Lack of influence of caffeine and aspirin on lithium elimination. Clin Res 1982; 30:249.
- Newall CA, Anderson LA, & Phillipson JDNewall CA, Anderson LA, & Phillipson JD: Herbal Medicines: A Guide for Health-Care Professionals, The Pharmaceutical Press, London, England, 1996, pp 189-190.
Keep reading about Lithium Carbonate
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist