Terminalia Arjuna (Oxyjun®)

Terminalia arjuna
Evidence Level
Moderate
2 Clinical Trials
5 Documented Benefits
3/5 Evidence Score

Terminalia arjuna is a large deciduous tree native to India whose bark has been used in Ayurvedic cardiology for over 3,000 years — described in the Ashtanga Hridayam as the premier cardiac tonic. Modern research validates its traditional use: arjuna bark extract significantly improves cardiorespiratory endurance, reduces exercise-induced oxidative stress, lowers blood pressure, and improves heart failure symptoms. Oxyjun® (OmniActive Health Technologies) is the first standardized arjuna extract with human RCT data specifically for exercise performance.

Studied Dose 500 mg/day Oxyjun®; traditional cardiac use: 1–3 g/day bark powder; effects on cardiorespiratory fitness at 4 weeks
Active Compound Arjunolic acid, arjunic acid, arjunetin, terminoic acid, and tannins — Oxyjun® by OmniActive Health Technologies (standardized Terminalia arjuna bark extract)

Cardiorespiratory endurance improvement

A 4-week human RCT of Oxyjun® (500 mg/day) demonstrated a significant 10-point increase in VO2 max scores in healthy adults compared to no change in placebo — a meaningful improvement in aerobic capacity attributable to improved cardiac output and oxygen utilization.

Cardiovascular protection and heart failure

Multiple clinical studies in heart failure patients show arjuna bark extract significantly improves ejection fraction, reduces angina frequency, and improves exercise tolerance. One study in stable angina patients showed arjuna was equivalent to isosorbide mononitrate for angina prevention over 3 months.

Blood pressure and arterial health

Arjuna extract reduces systolic and diastolic blood pressure through endothelial nitric oxide enhancement and direct smooth muscle relaxation. Clinical studies show 4–10 mmHg reductions in hypertensive patients with consistent supplementation.

Exercise-induced oxidative stress reduction

Arjuna's rich tannin and flavonoid content provides potent antioxidant protection against exercise-induced reactive oxygen species, reducing post-exercise lipid peroxidation, muscle damage markers, and recovery time.

Lipid profile improvement

Clinical studies show arjuna extract reduces total cholesterol, LDL, and triglycerides while improving HDL levels. The mechanisms include HMG-CoA reductase inhibition and increased hepatic LDL receptor expression.

1

Endothelial nitric oxide enhancement

Arjunolic acid and arjunic acid stimulate endothelial nitric oxide synthase (eNOS) activity and increase bioavailable nitric oxide — improving vascular tone, reducing blood pressure, and enhancing blood flow to working muscle tissue during exercise. This mechanism underlies both cardiovascular protection and performance enhancement.

2

Cardiac muscle calcium channel modulation

Arjuna glycosides modulate cardiac L-type calcium channels, improving cardiac contractility and stroke volume without the proarrhythmic risks associated with pharmaceutical calcium channel modulators. This inotropic effect explains improvements in ejection fraction in heart failure patients.

3

Free radical scavenging and antioxidant enzyme induction

Arjuna's dense tannin matrix (including arjunagenin and terminic acid) directly scavenges reactive oxygen species and induces endogenous antioxidant enzyme expression (SOD, catalase, GPx), providing both immediate and sustained antioxidant protection in cardiac and vascular tissue.

1
Oxyjun® and VO2 Max in Healthy Adults — RCT
PubMed

Randomized, double-blind, placebo-controlled trial of Oxyjun® (500 mg/day) vs. placebo in 30 healthy adults for 4 weeks.

30 healthy adults. 4-week intervention.

Oxyjun® supplementation produced a significant 10-point increase in VO2 max score vs. no change in placebo. Significant improvements in cardiorespiratory fitness markers and exercise performance indices. Well-tolerated with no adverse effects.

2
Terminalia arjuna vs. Isosorbide Mononitrate in Stable Angina — RCT
PubMed

Randomized crossover trial comparing arjuna bark extract (500 mg three times daily) vs. isosorbide mononitrate (40 mg/day) vs. placebo in 58 stable angina patients over 3 months.

58 stable angina patients. 3-month crossover design.

Arjuna extract significantly reduced angina frequency, improved exercise tolerance on treadmill test, and improved left ventricular ejection fraction. Efficacy comparable to isosorbide mononitrate with better tolerability profile.

Common Potential side effects

Generally well tolerated at supplemental doses
High-dose whole bark preparations may cause mild GI discomfort
Potential for excessive blood pressure lowering in already-hypotensive individuals

Important Drug interactions

Antihypertensive medications — additive blood pressure-lowering effects; monitor blood pressure
Cardiac medications (digoxin, beta-blockers, calcium channel blockers) — arjuna has direct cardiac effects; potential additive or synergistic effects; monitor cardiac parameters
Anticoagulants — tannin content may mildly affect coagulation; monitor with warfarin
Antidiabetic medications — mild glucose-lowering activity; monitor blood sugar