Originally, “pycnogenols” referred to oligomeric proanthocyanidins (OPCs) extracted from various plants (including grape seeds) and separated from their tannins. OPCs are chains of up to 5 units of proanthocyanidins (a category of flavonoids), such as catechins.  “Pycnogenol” was later trademarked in the United States and now refers only to a mixture of compounds, including OPCs, extracted from the bark of the French maritime pine tree.

Pycnogenol contains many antioxidants. However, there is no certainty that, once absorbed and metabolized, the compounds retain their antioxidant function. Nevertheless, compounds of Pycnogenol produce preventive and therapeutic effects in the body, as shown by studies that support the following uses.



Children and teenagers who took Pycnogenol (1 mg per pound of body weight) for 3 months had greater improvements in lung function and fewer asthma symptoms than others who took a placebo. Those who took Pycnogenol were also more likely to have reduced need for inhalers.[1]


Subjects with osteoarthritis who took 100 mg of Pycnogenol per day for 3 months improved their scores on an arthritis questionnaire by 56% compared to 10% for those who took a placebo. Walking distance increased from 68 to 198 meters for those in the Pycnogenol group and from 65 to 88 meters in the placebo group. The use of drugs decreased by 58% in the Pycnogenol group and 1% in the placebo group. Edema decreased 79% with Pycnogenol and 1% with placebo.[2] Similar success was reported in another study for patients with knee osteoarthritis who took 150 mg of Pycnogenol daily for 3 months.[3]

Menstrual pain

Pycnogenol relieved pain and lowered the need for analgesic medication among women experiencing menstrual pain in a study comparing 60 mg/day of Pycnogenol and a placebo. The supplements were taken daily for two months; after discontinuation of Pycnogenol supplementation, the required analgesic medication remained significantly lower than before supplementation.[4]

Male sexual function

For men, a proprietary combination of Pycnogenol and the amino acid L-arginine (Prelox®) can help reverse erectile dysfunction. In one study, researchers found that 3 grams of L-arginine daily benefited only two of 40 male subjects. But with the addition of 80 mg of Pycnogenol daily, 32 of the men had improvements in erectile function. In a separate year-long study of 50 men with erectile dysfunction, 80 percent benefited from the combination of L-arginine and Pycnogenol. During the study, the partners of almost half the men became pregnant.[5] In another study, treatment with Prelox® for 1 month restored erectile function to normal and intercourse frequency doubled. Testosterone levels in blood increased significantly.[6]

Menopausal symptoms

Symptoms of menopause improved for women taking 200 mg of Pycnogenol daily in a double-blind, placebo-controlled trial. In addition, the ratio of LDL-cholesterol to HDL-cholesterol was favorably altered.[7]

Diabetes and its complications

Pycnogenol can reduce some of the signs and complications of diabetes. In one study, 77 people with type 2 diabetes took either 100 mg of Pycnogenol or a placebo for 12 weeks. Patients taking Pycnogeneol showed significant reductions in blood sugar and a modest decline in glycated hemoglobin, a marker of diabetic control. They also had improvements in blood vessel tone that could lower their risk of heart disease.[8]

A different group of researchers analyzed five clinical trials involving almost 1300 patients and found that Pycnogenol supplements slowed the progression of diabetic retinopathy. Pycnogenol reduced blood leakage into the retina—a hallmark of the eye disease—and it also improved visual acuity. The dosages ranged from 60 to 150 mg daily.[9]

Pycnogenol has also helped heal diabetic ulcers. At 6 weeks in one study there was 85% or greater healing of diabetic ulcers in subjects who used oral and/or topical Pycnogenol, compared to 61% among those receiving medications only (no Pycnogenol).[10]

High blood pressure

The flavonoids in Pycnogenol play a key role in maintaining normal blood vessel tone and integrity. Researchers asked 58 patients with high blood pressure to take 100 mg of Pycnogenol daily for 12 weeks. The supplements improved blood vessel flexibility, and many of the patients were able to safely reduce their dosage of calcium antagonists, a type of medication used to treat hypertension.[11]

Chronic venous insufficiency (CVI)

CVI is a condition in which the veins of the legs lose the ability to pump blood back to the heart. Symptoms of CVI include varicose veins, swelling or edema of the legs and ankles, and legs that feel tired, heavy, achy or restless. Patients with CVI who were treated with 150 mg of Pycnogenol per day showed improvement at 4 weeks and 8 weeks, with decreased edema and significant improvement in symptoms. There were no visible effects in untreated patients.[12]

How Much To Take


Children, 1 mg per pound body weight daily

Erectile dysfunction

80 mg of Pycnogenol and 3000 mg of L-arginine daily for two weeks, then reduce by half.

Most other conditions

100 to 150 mg daily.


Pycnogenol is safe and well-tolerated. Because Pycnogenol can stimulate the immune system, it theoretically could interfere with immunosuppressive therapy or adversely affect individuals with autoimmune diseases.[13]


[1] Lau BHS et al. Pycnogenol® as an adjunct in the management of childhood asthma. J Asthma 2004; 41:825-832.

[2] Belcaro G et al. Treatment of osteoarthritis with Pycnogenol. The SVOS (San Valentino Osteoarthrosis Study). Evaluation of signs, symptoms, physical performance and vascular aspects. Phytother Res 2008; 22(4):518-523.

[3] Cisar P et al. Effect of pine bark extract (Pycnogenol®) on symptoms of knee osteoarthritis.

[4] Suzuki N et al. French maritime pine bark extract significantly lowers the requirement for analgesic medication in dysmenorrhea: a multicenter, randomized, double-blind, placebo-controlled study. J Reprod Med 2008; 53(5):338-346.

[5] Lamm S et al. Prelox for improvement of erectile function: a review: Euro Bull Drug Res 2003; 11:29-37.

[6] Stanislavov R et al. Improvement of erectile function with Prelox: a randomized, double-blind, placebo-controlled crossover trial. Int J Impot Res 2008; 20(2):173-180.

[7] Yang HM et al. A randomized, double-blind, placebo-controlled trial on the effect of Pycnogenol on the climacteric syndrome in peri-menopauseal women. Acta Obstet Gynecol Scand 2007; 86(8):978-985.

[8] Liu X et al. Antidiabetic effect of Pycnogenol French maritime pine bark extract in patients with diabetes type II. Life Sciences 2004; 74:855-862.

[9]Schonlau F et al. Pycnogenol® for diabetic retinopathy. Int Ophthamol 2002; 24:161-171.

[10] Belcaro G et al. Diabetic ulcers: microcirculatory improvement and faster healing with pycnogenol. Clin Appl Thromb Hemost 2006; 12(3):318-323.

[11] Liu X et al. Pycnogenol®, French maritime pine bark extract, improves endothelial functionof hypertensive patients. Life Sciences 2004; 74:855-862.

[12] Cesarone MR et al. Rapid relief of signs/symptoms I chronic venous microangiopathy with pycnogenol: a prospective, controlled study. Angiology 2006; 57(5):569-576.

[13] “Pycnogenol,” Natural Medicines Comprehensive Database (July 2008),