The short answer
It is not established that bearberry adds to chlorthalidone-related side effects. The main practical issue is reviewing the exact leaf product and kidney history, without assuming traditional urinary use proves an interaction.
What this answer covers
Arctostaphylos uva-ursi species entry; regulatory evidence concerns specified oral leaf preparations.
- Supplement or preparation
- Arctostaphylos uva-ursi
- Medication ingredient
- chlorthalidone
What is known about the combination
The bearberry leaf monograph reports no interactions, and the reviewed sources do not demonstrate extra hypotension with chlorthalidone. A lack of reports is not proof that every preparation is safe.
Why kidney history matters
The monograph contraindicates these leaf products in women with kidney disorders. Chlorthalidone can worsen kidney function if too much fluid is lost. These separate precautions support a product review but do not establish additive blood-pressure lowering.
The plant part matters
The monograph concerns leaf preparations for short-term lower urinary symptoms. It does not evaluate all extracts, other plant parts or multi-herb blends. The actual ingredients and preparation should be checked rather than relying on the word bearberry.
Respond to symptoms
Tell the treating team about new urinary or weight-loss products, dizziness, faintness, marked thirst or reduced fluid intake. Chlorthalidone can itself cause excess fluid loss and kidney problems. Follow your existing fluid plan rather than increasing fluids or changing chlorthalidone on your own.
Evidence and practical considerations
Side effects & toxicity
Available preparation-specific guidance and indirect human studies do not establish this exact-pair adverse outcome; absence of proof is not proof of safety.
- Exact scope
- Arctostaphylos uva-ursi species entry; regulatory evidence concerns specified oral leaf preparations. with Oral chlorthalidone, exact RxCUI2409 IN. No automatic transfer from loop diuretics or another thiazide.
- Medication form and route
- oral medication; oral supplement
What remains uncertain
- No universal risk rate or spacing interval; individual source limitations apply.
Factors that may matter: Preparation and plant part; Dose and duration; Kidney function; Fluid status; Other medicines; Calcium or potassium status.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People treated with oral chlorthalidone
Can cause fluid and electrolyte disturbances, including low potassium and sodium. Reduces urinary calcium excretion and can raise serum calcium; substantial elevation needs evaluation.
How this applies: Exact medication, salt, route, plant part, formulation and clinical endpoint govern applicability.
Exact oral product; not another thiazide or loop diuretic. Chlorothiazide sodium intravenous therapy is a separate route and salt. THALITONE has product-specific bioavailability and should not be assumed dose-for-dose identical to other formulations.
Source 2: regulatory guidance
ema.europa.eu · Source check Sep 10, 2026
Population: People using the specified oral preparation.
No interactions reported. The covered leaf products are contraindicated in women with kidney disorders.
How this applies: Interpret only for the stated species, preparation, route and endpoints; exact chlorthalidone pair evidence is distinguished.
Not a chlorthalidone combination or human blood-pressure study; species-level identity does not identify every preparation.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Prepared exact-pair article with separately verified drug label, original human evidence and explicit preparation and endpoint limitations. | |
| Research summary published |
Article revision: 8063de76ee7f493a
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.