More than 10 million Americans have knee osteoarthritis. If you're one of them, you may benefit from pine bark extract.

You may already be familiar with pine bark extract, commonly sold as pygenol, or under the brand name Pycnogenol®. Years of research have shown that this supplement, which is a standardized extract of bark from the pine trees growing along the southwestern coast of France, is a potentially effective treatment for varicose veins, menstrual pain, high blood pressure, and asthma. However, recent studies suggest that pine bark extract may have another application: it could help reduce some symptoms of knee osteoarthritis.

Knee osteoarthritis, like other forms of osteoarthritis, is the breakdown of cartilage (connective tissue) and the joints of bones. It occurs when cartilage loses its elasticity. Once cartilage hardens and begins to crack, it's more likely to be further damaged by slight injuries or just everyday use. Ultimately, the joint becomes inflamed, and the classic symptoms of pain, stiffness, and decreased function start to surface.

Pine bark extract is thought to inhibit inflammation in the body. An Italian study of knee osteoarthritis patients, published in a 2008 issue of Phytotherapy Research, found that those who took Pycnogenol® along with any pain medication they were already taking experienced several significant benefits, including:

  • diminished joint pain
  • less stiffness
  • enhanced well-being and overall physical function
  • reduced need for pain medication, resulting in fewer side effects from those drugs

Pine bark extract is considered safe, has few side effects, and is found in a wide variety of supplements. Among the active ingredients in pine bark extract are health-promoting antioxidants known as phenolic compounds, which are also found in tea, red wine, apples, blueberries, and cranberries. Since pine bark extract may cause minor gastrointestinal discomfort and urinary retention or frequency in some people, it's not for everyone. Also, some of the research on pine bark extract's effectiveness in treating conditions like high blood pressure has been disputed. Research is continuing, so recommendations for use may change over time.

But for now, pine bark extract may be worth investigating. If you have knee arthritis, speak with your health care provider to see if pygenol is right for you and, if so, in what form and at what dose.


Cisar P, et al. "Effect of Pine Bark Extract (Pycnogenol) on Symptoms of Knee Osteoarthritis." Phytotherapy Research. Aug 2008; 22(8):1087-92 Web. 1 Feb 2012.

D'andrea G. "Pycnogenol: A Blend of Procyanidins with Multifaceted Therapeutic Applications?" Fitotherapia. Oct 2010; 81(7):724-36 Web. 1 Feb 2012.

Rohdewald, P. "A Review of the French Maritime Pine Bark Extract (Pycnogenol), a Herbal Medication with a Diverse Pharmacology." International Journal of Clinical Pharmacology and Therapeutics. Apr 2002; 40(4):158-68. Web. 1 Feb 2012.

Stanford University School of Medicine: Pine Bark Research Study/Stanford Antioxidant Natural Supplement Study. Web. 1 Feb 2012.