Pycnogenol, a standardized extract from the bark of the French maritime pine (Pinus pinaster), has been studied for its potential benefits in managing diabetic retinopathy. Evidence for its use is primarily derived from several clinical trials and mechanistic studies. Pycnogenol is rich in procyanidins, bioflavonoids, and phenolic acids, compounds known for their antioxidant and anti-inflammatory properties.

Several randomized controlled trials (RCTs) have examined the impact of Pycnogenol on early-stage diabetic retinopathy. Studies have shown that supplementation can help improve retinal microcirculation, reduce retinal edema, and maintain visual acuity in patients with mild to moderate retinopathy. For example, a study published in Diabetes Research and Clinical Practice (2002) found that patients receiving Pycnogenol had significantly less retinal edema compared to placebo. Other trials have reported improvements in capillary permeability and stabilization of visual function.

The proposed mechanisms include Pycnogenol’s ability to strengthen capillary walls, inhibit platelet aggregation, and reduce oxidative stress—all factors implicated in the progression of diabetic retinopathy. While these studies are promising, the majority are small and of short duration. Larger, long-term studies are needed to confirm efficacy and safety. Most clinical guidelines do not currently endorse Pycnogenol as standard therapy, but there is moderate scientific support for its adjunctive use in early retinopathy.