White Willow Bark
Research reviewed: Up until 03/2026
White Willow Bark (Salix alba) is a dietary supplement with 6 published peer-reviewed studies involving 627 participants, researched for Arthritis & Joint Pain, Back Pain, Anti-Inflammatory Mechanisms.
Evidence at a Glance
Strength is scored by study design, sample size, study type, and outcomes
Arthritis & Joint Pain
ModerateBack Pain
ModerateAnti-Inflammatory Mechanisms
ModerateResearch Visualised
Visual breakdown of the clinical data.
Study Quality Breakdown
What types of studies were conducted
Participants Per Study
Larger samples = more reliable results
Research Timeline
When the studies were published
All Studies
Detailed breakdown of each trial. Click to expand.
Arthritis & Joint Pain
To evaluate willow bark extract efficacy for pain relief in arthritis
Study Type
Meta-analysis of randomized controlled trials
Purpose
To evaluate willow bark extract efficacy for pain relief in arthritis
Dose
Various willow bark extracts (120-240 mg salicin/day)
Participants
Meta-analysis of 5 studies with 6 RCTs, 329 arthritis patients
Duration
6 weeks typical
Results
Significant differences in pain relief and improvement in physical status between willow bark and placebo groups for arthritis.
How They Measured It
Pain scores, physical status improvement
To evaluate willow bark extract efficacy and tolerability in osteoarthritis and rheumatoid arthritis
Study Type
Randomized, controlled, double-blind trial
Purpose
To evaluate willow bark extract efficacy and tolerability in osteoarthritis and rheumatoid arthritis
Dose
Willow bark extract 240 mg salicin/day vs diclofenac 100 mg/day
Participants
127 hip/knee OA patients, 26 RA patients
Duration
6 weeks
Results
Willow bark showed no relevant efficacy in OA or RA compared to placebo, though numerically lower than diclofenac group.
How They Measured It
WOMAC pain scores, rheumatoid arthritis pain
Back Pain
To evaluate standardized willow bark extract for osteoarthritis pain relief
Study Type
Randomized, placebo-controlled, double-blind
Purpose
To evaluate standardized willow bark extract for osteoarthritis pain relief
Dose
Willow bark extract (120 mg salicin equivalent)
Participants
OA patients
Duration
2-4 weeks
Results
WOMAC pain score reduced by 14% from baseline after 2 weeks active treatment vs 2% increase in placebo (statistically significant).
How They Measured It
WOMAC pain dimension
To evaluate willow bark extract for chronic low back pain treatment
Study Type
Randomized, double-blind, placebo-controlled
Purpose
To evaluate willow bark extract for chronic low back pain treatment
Dose
Willow bark extract 120 mg or 240 mg salicin/day
Participants
210 patients with chronic low back pain
Duration
4 weeks
Results
39% of high-dose extract patients pain-free without rescue medication in final week vs 6% in placebo (p<0.05).
How They Measured It
Pain-free status without rescue medication, pain scores
To evaluate willow bark extract for acute low back pain exacerbations
Study Type
Randomized, double-blind, placebo-controlled
Purpose
To evaluate willow bark extract for acute low back pain exacerbations
Dose
Willow bark extract
Participants
Patients with low back pain exacerbation
Duration
2 weeks
Results
Willow bark extract showed significant benefit for acute low back pain exacerbations vs placebo.
How They Measured It
Pain scores, functional improvement
Anti-Inflammatory Mechanisms
To review white willow bark mechanism of action as anti-inflammatory and analgesic
Study Type
Review article
Purpose
To review white willow bark mechanism of action as anti-inflammatory and analgesic
Dose
Typical 120-240 mg salicin/day
Participants
Various study populations
Duration
Various
Results
Willow bark active salicin acts as COX-1 and COX-2 inhibitor, effective anti-inflammatory and analgesic by blocking prostaglandin release.
How They Measured It
Literature synthesis of mechanism studies
Frequently Asked Questions
Common questions about White Willow Bark research
There are currently 8 peer-reviewed studies on White Willow Bark (Salix alba), involving 627 total participants. Research covers Pain relief, Anti-inflammatory, Arthritis support. The overall evidence strength is rated as Strong.
The evidence is currently rated as "Strong Evidence". This rating is based on study design quality (randomisation, blinding, placebo controls), sample sizes, study types (6 human studies), and reported outcomes.
White Willow Bark has been researched for: Pain relief, Anti-inflammatory, Arthritis support. Each area has its own body of evidence which you can explore in the study breakdowns above.
Yes, 6 out of 8 studies are human trials. Human trials carry more weight in our evidence scoring system.
