Java Tea

Metadata

Approved Indications

Commission E (Germany)

• Approved: Irrigation therapy for:
  • Bacterial and inflammatory diseases of the lower urinary tract
  • Urinary gravel (Harngruess)
• Must be used with copious fluid intake (irrigation therapy principle)

ESCOP

• No monograph — Not included in ESCOP monograph collection

EMA/HMPC

• Traditional use: Herbal medicinal product to increase the amount of urine to achieve flushing of the urinary tract as an adjuvant in minor urinary complaints
• Based on long-standing traditional use (at least 30 years, including 15 years within the EU)

Agreement/Disagreement Between Bodies

Commission E is notably more assertive than EMA/HMPC in its assessment. Commission E explicitly names bacterial and inflammatory urinary tract diseases and urinary gravel as approved indications, while EMA restricts its monograph to the more conservative “minor urinary complaints” with traditional use status. The absence of an ESCOP monograph reflects the limited clinical trial data. The overall pattern is typical of irrigation therapy herbs: pharmacologically plausible mechanism, strong traditional use, but insufficient modern RCT evidence.

Conditions Treated

Primary

• Urinary tract irrigation therapy (Durchspuelungstherapie)
• Bacterial and inflammatory diseases of the lower urinary tract (adjuvant, not primary antimicrobial)
• Urinary gravel (Harngruess) prevention and supportive treatment

Secondary

• Minor urinary complaints (dysuria, urinary frequency)
• Adjuvant in urinary tract infection management (alongside appropriate antimicrobial therapy)

Traditional/Historical

• Kidney stones (traditional Southeast Asian use)
• Gout and hyperuricemia (traditional, based on proposed uricosuric effect)
• Diabetes (traditional use in Southeast Asia; not supported by European monographs)
• Hypertension (folk medicine; not an approved indication)
• Rheumatic conditions (traditional Southeast Asian medicine)

Mechanism of Action

Key Active Constituents

• Polymethoxylated flavonoids: Sinensetin, eupatorin, 3’-hydroxy-5,6,7,4’-tetramethoxyflavone — lipophilic flavonoids with anti-inflammatory and diuretic properties
• Rosmarinic acid: Major phenolic compound; antioxidant and anti-inflammatory
• Potassium salts: High potassium content (2.5-3.5% of dry weight) contributes to aquaretic effect
• Diterpenes: Orthosiphol A-E, staminol A-B — biologically active terpenoids
• Caffeic acid derivatives: Including cichoric acid
• Essential oil: Minor component

Proposed Mechanisms

1. Aquaretic (Diuretic) Effect

   • Increases urine volume without proportional electrolyte loss (aquaretic rather than saluretic)
   • High potassium salt content promotes osmotic diuresis
   • Flavonoids may enhance glomerular filtration rate and renal blood flow
   • In vivo animal studies confirm dose-dependent diuretic activity (Englert & Harnischfeger, 1992)
   • The aquaretic effect distinguishes Java tea from loop or thiazide diuretics, which cause significant potassium and sodium loss

2. Anti-inflammatory Activity

   • Sinensetin and eupatorin inhibit COX-2 and iNOS expression (in vitro)
   • Rosmarinic acid suppresses NF-kB activation
   • Contributes to relief of inflammatory symptoms in urinary tract

3. Litholytic/Anti-lithogenic Effect

   • Traditional use for kidney stones and urinary gravel
   • Increased urine volume dilutes crystal-forming substances
   • Some in vitro evidence suggests inhibition of calcium oxalate crystallization
   • Uricosuric effect reported in older pharmacological studies (increased uric acid excretion)

4. Antioxidant Activity

   • Rosmarinic acid and flavonoids contribute strong antioxidant capacity
   • May protect renal tissue from oxidative damage

5. Mild Spasmolytic Effect

   • Smooth muscle relaxation in urinary tract (in vitro data)
   • May contribute to relief of colicky pain associated with urinary gravel

Pharmacokinetics

• Sinensetin and eupatorin are absorbed orally; bioavailability data in humans is limited
• Rosmarinic acid is partially absorbed and undergoes extensive first-pass metabolism
• Potassium salts are well-absorbed
• The aquaretic effect onset is relatively rapid (within hours of administration)

Clinical Evidence Summary

Clinical Studies

• Limited published RCTs — No large, well-designed placebo-controlled trials identified for Java tea monotherapy in urinary conditions
• Older German pharmacological studies (1960s-1990s) confirmed diuretic activity in healthy volunteers
• Schilcher (1992): Reported increased urine volume and sodium excretion in a controlled study with healthy volunteers receiving Java tea infusion
• Muanza et al. (1995): Pharmacological confirmation of anti-inflammatory properties

Pharmacological Evidence

• Diuretic activity: Well-confirmed in multiple animal models (rats, mice); dose-dependent increase in urine volume
• Anti-inflammatory: Sinensetin and eupatorin demonstrated inhibition of pro-inflammatory mediators in vitro
• Antioxidant: Strong antioxidant capacity confirmed in multiple in vitro assays (DPPH, FRAP, ORAC)
• Anti-lithogenic: In vitro inhibition of calcium oxalate crystallization reported

Evidence in Context

• Java tea shares the evidence profile typical of European irrigation therapy herbs: strong pharmacological rationale, long traditional use, Commission E approval, but limited modern clinical trial evidence
• Compare with goldenrod (similar regulatory and evidence profile for the same indication)
• The Commission E positive monograph provides more regulatory weight than many irrigation therapy herbs receive
• Evidence rating D reflects Commission E approval with pharmacological support but limited clinical trials

Evidence Limitations

• No large, modern RCTs for urinary tract indications
• Most pharmacological studies are older (1980s-1990s)
• The irrigation therapy concept makes placebo-controlled trials methodologically challenging
• Traditional use in Southeast Asia for diverse conditions (diabetes, hypertension) is not supported by the European regulatory assessment

European vs. US/Anglophone Consensus

Safety Profile

Contraindications

• Conditions requiring reduced fluid intake: Severe cardiac insufficiency, severe renal failure, or edema due to cardiac/renal failure — because irrigation therapy requires high fluid intake (minimum 2 liters/day)
• Known hypersensitivity to Orthosiphon stamineus or other Lamiaceae family members
• Acute urinary obstruction: Irrigation therapy is inappropriate when urinary flow is obstructed

Drug Interactions

• No clinically significant drug interactions documented
• Theoretical considerations:
  • Diuretics: Possible additive diuretic effect (theoretical)
  • Lithium: Diuretic effect could theoretically alter lithium levels (no reports)
• The absence of documented interactions may reflect limited investigation rather than confirmed safety

Side Effects

• Very rare: Mild GI discomfort (stomach upset)
• Very rare: Allergic reactions
• Overall: Excellent safety profile at recommended doses; adverse event reports are extremely rare
• In traditional Southeast Asian use over centuries, no significant toxicity has been reported

Pregnancy/Lactation

• Pregnancy: Not recommended due to insufficient safety data. No reproductive toxicity studies identified. EMA does not recommend use during pregnancy.
• Lactation: Not recommended due to insufficient safety data

Clinical Dosage

Recommended Forms and Doses

Critical: Fluid Intake Requirement

• During irrigation therapy, patients MUST maintain fluid intake of at least 2 liters per day
• This is essential to the therapeutic principle — the herb increases urine volume, but adequate fluid input is required for effective flushing
• Failure to maintain adequate hydration negates the therapeutic approach and may concentrate urinary solutes

Key European Products

• Indischer Nierentee (German pharmacy tea) — standardized Java tea preparation
• Orthosiphon Blätter (loose leaf, pharmacopoeia quality)
• Available as registered herbal medicine in Germany and several other EU countries
• Often combined with other irrigation therapy herbs (goldenrod, birch leaf, horsetail) in commercial blends

Duration of Treatment

• 2-4 weeks for initial assessment
• Can be used long-term for prevention of urinary gravel recurrence
• Consult a physician if symptoms persist beyond 2 weeks, worsen, or if fever, hematuria, or urinary retention develop

Sources

• German Commission E Monograph: Orthosiphonis folium. Bundesanzeiger, 1991.
• EMA/HMPC. Community herbal monograph on Orthosiphon stamineus Benth., folium. European Medicines Agency, 2010.
• EMA/HMPC. Assessment report on Orthosiphon stamineus Benth., folium. European Medicines Agency.
• Englert J, Harnischfeger G. Diuretic action of aqueous Orthosiphon extract in rats. Planta Med. 1992;58(3):237-238.
• Schilcher H. Orthosiphon — der Katzenbart. Dtsch Apoth Ztg. 1992;132:1039-1045.
• Ameer OZ et al. Orthosiphon stamineus: Traditional uses, phytochemistry, pharmacology, and toxicology. J Med Food. 2012;15(8):678-690.
• Arafat OM et al. Studies on diuretic and hypouricemic effects of Orthosiphon stamineus. J Ethnopharmacol. 2008;118(3):354-360.
• Stampoulis P et al. Staminolactones A and B and norstaminol A: three highly oxygenated staminane-type diterpenes from Orthosiphon stamineus. Tetrahedron Lett. 1999;40(23):4239-4242.
• Wichtl M. Herbal Drugs and Phytopharmaceuticals: A Handbook for Practice on a Scientific Basis. 3rd ed. CRC Press; 2004.

Connections

• Compare irrigation therapy approach with Goldenrod (strongest evidence among European irrigation therapy herbs)
• See Birch Leaf and Horsetail for other irrigation therapy herbs
• Compare urinary antiseptic approach with Bearberry Uva Ursi (antimicrobial mechanism vs. irrigation)
• Compare UTI prevention approach with Cranberry (anti-adhesion mechanism vs. mechanical flushing)