, Volume 27, Issue 3, pp 475–485 | Cite as

A double-blind randomized placebo controlled study assessing safety, tolerability and efficacy of palmitoylethanolamide for symptoms of knee osteoarthritis

  • Elizabeth SteelsEmail author
  • Ruchitha Venkatesh
  • Eleanor Steels
  • Gemma Vitetta
  • Luis Vitetta
Original Article



The aim of the study was to assess the safety, tolerability and efficacy of palmitoylethanolamide (PEA) when dosed at 300 mg and 600 mg per day on symptoms of knee osteoarthritis.


This was a single site, comparative, double-blind placebo controlled study in adults with mild to moderate knee osteoarthritis with 111 participants randomized to receive 300 mg PEA, 600 mg PEA or placebo each day, in divided doses b.i.d, for 8 weeks. The primary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The secondary outcomes were the Numerical Rating Scales (NRS) for pain, the Depression Anxiety Stress Scale (DASS), the Perceived Stress Scale (PSS), the Pittsburg Sleep Quality Index (PSQI), the Short Form Health Survey (SF-36), the use of rescue pain medication and clinical safety assessment.


There was a significant reduction in the total WOMAC score in the 300 mg PEA (p = 0.0372) and the 600 mg PEA (p = 0.0012) groups, the WOMAC pain score (300 mg PEA, p = 0.0074; 600 mg PEA, p =  < 0.001), the WOMAC stiffness score (PEA 300 mg, p < 0.0490; 600 mg PEA, p = 0.001) and in the WOMAC function score in the 600 mg PEA group (p = 0.033) compared to placebo. The NRS pain evaluations for "worst pain" and "least pain" were significantly reduced in the 300 mg PEA group (p < 0.001, p = 0.005) and the 600 mg PEA group (p < 0.001, p < 0.001) compared to placebo. There was a significant reduction in anxiety (DASS) in both active treatment groups (300 mg PEA, p = 0.042; 600 mg PEA group (p = 0.043) compared to placebo. There were no changes in the clinical markers and the product was well tolerated.


The study demonstrated that palmitoylethanolamide may be a novel treatment for attenuating pain and reducing other associated symptoms of knee osteoarthritis. Further studies on the pharmacological basis of this anti-inflammatory effect are now required.


Inflammation Osteoarthritis Pain Palmitoylethanolamide N-acylethanolamines 


Compliance with ethical standards

Conflict of interest

Luis Vitetta has received National Institute of Complementary Medicine and National Health and Medical Research Council of Australia competitive funding and Industry support for research into nutraceuticals and herbal medicines. This research project was industry funded. None of the authors have a commercial interest in the investigative product. None of the authors have declared any conflict of interest.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.The University of Sydney, Faculty of Medicine and Health, Sydney Medical SchoolSydneyAustralia
  2. 2.University of the Sunshine Coast, Facility of Science, Health, Education and EngineeringSippy DownsAustralia
  3. 3.University of Hong KongDepartment of MedicineHong KongChina
  4. 4.Queensland University of TechnologyBrisbaneAustralia
  5. 5.Medlab ClinicalSydneyAustralia

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