Research
Java tea for Bladder Health: Evidence, Interactions and Cautions
Java tea is an ingredient used in bladder supplements marketed to women. Below is what it has actually been studied for, how strong that evidence is, the drug interactions and cautions on record, and the primary source our grade rests on — all drawn from the HerWellReport ingredient dataset.
Also sold as: Orthosiphon aristatus; Orthosiphon stamineus; Orthosiphonis folium; cat's whiskers; kumis kucing
What the evidence says about Java tea
Registered by the EMA on traditional use only. Its assessment report identified just two human studies: an open study in 67 patients showing a 15% rise in urine output, which the report notes was weaker than horsetail, and a placebo-controlled trial in 76 people with kidney stones that found no statistically significant difference from placebo. So the single controlled trial was negative. The committee accepted the indication on safety and long use rather than on proven effect.
The grade "traditional" means: traditional — A long history of use but little or no human trial evidence for this outcome. Grades are explained in full on our methodology page.
Read the primary source this grade rests on (opens in a new tab).
Java tea drug interactions
No documented drug interactions in the sources we checked. That is not the same as proof of safety alongside your medication — it usually means the question has not been studied. Ask a pharmacist before combining it with prescription drugs.
Who should be careful with Java tea
- Not if you have been told to restrict fluids, for example in severe heart or kidney disease
- Not in pregnancy or breastfeeding
- Not under 18 years
- See a doctor if symptoms persist beyond 2 weeks
Read more on HerWellReport
This entry is generated from row "Java tea" of the HerWellReport ingredient dataset (v2.1, updated 2026-09-23). The dataset is free to reuse under CC BY 4.0 — how to cite it. Ingredient evidence is not evidence for any finished product, and nothing here is medical advice.