Anthocyanidins, a class of flavonoid compounds found in fruits and vegetables (notably berries, grapes, and red cabbage), have a long history of use in traditional and herbal medicine primarily for vascular health. Their application in the context of hemorrhoids is largely based on traditional and empirical uses, especially in European herbal medicine, where extracts rich in anthocyanidins (often termed "bioflavonoids" or "phlebotonics") have been used to support venous tone and reduce symptoms such as swelling, pain, and bleeding associated with hemorrhoidal disease.

The rationale is that anthocyanidins may strengthen capillary walls, reduce vascular permeability, and exert antioxidant and anti-inflammatory effects, which are potentially beneficial in the context of hemorrhoids—a condition characterized by swollen and inflamed veins in the rectal area. However, direct high-quality scientific studies specifically on anthocyanidins (as isolated compounds) for hemorrhoid treatment are limited. Most clinical studies have been conducted with complex mixtures or extracts (such as those containing diosmin, hesperidin, or generic "flavonoids"), and only a few mention anthocyanidin-rich preparations specifically.

Consequently, while traditional use and some mechanistic plausibility exist, scientific validation is limited, and the evidence base is not robust. Most recommendations are extrapolated from broader research on flavonoids and vascular health rather than direct clinical trials with anthocyanidins for hemorrhoids.