A substance which is normally harmless that provokes an immune response and thus and allergic reaction. While some people have no reaction to pollen, others may have an allergic reaction. The same is true for a wide range of scents, odors, foods and natural substances.
Daily Hair Tip
When blow drying hair always apply a protective leave in conditioner and hold nozzle at least 6 inches away from your scalp. Dry on lowest, coolest setting for extra protection.