Aloe polysaccharides, particularly acemannan, are major bioactive components in Aloe vera gel and are traditionally used for their soothing and healing properties on the skin. Historical and ethnobotanical records show that Aloe vera gel has been applied topically for centuries to treat a variety of skin conditions, including rashes, hives (urticaria), and burns. The traditional use is based on Aloe’s perceived ability to reduce irritation, redness, and itching due to its cooling and moisturizing effects.

Scientifically, there is some evidence from in vitro and animal studies suggesting that Aloe polysaccharides have anti-inflammatory and immunomodulatory properties, which could theoretically benefit skin inflammation underlying rashes and hives. However, robust clinical trials in humans specifically addressing rashes or hives are lacking. Most clinical research has focused on Aloe’s effects on wound healing and minor burns, with mixed results. A few small studies and case reports suggest some benefit in dermatitis and allergic skin reactions, but these are not sufficient to draw strong conclusions.

In summary, while Aloe polysaccharides are widely used in traditional medicine for treating skin irritation, the scientific evidence specifically supporting their use for rashes and hives is limited and not conclusive. The rating reflects a strong tradition with limited preliminary scientific support but insufficient high-quality clinical evidence.