Salicylic Acid has 3 grades

External use of salicylic acid has antibacterial properties to microorganisms, and its antiseptic power is close to that of p-henol. Salicylic acid can dissolve keratin, and its pharmacological effects vary with the concentration of its preparation: 1%-3% has keratosis-promoting and antipruritic effects; common over-the-counter (OTC) salicylic acid shampoos available with 3% salicylic acid 5%-10% has a cutin dissolving effect, which can dissolve the adhesive between the connected squamous cells in the stratum corneum, thereby loosening the cutin and desquamating it, and can also produce antifungal effects (because the stratum corneum is removed and the growth of fungi is inhibited, Salicylic acid can help other antifungal drugs penetrate and inhibit bacterial growth). 25% has a corrosive effect and can remove the hypertrophic calluses. Suitable for seborrhea, seborrheic dermatitis, superficial mycosis, warts, corns, calluses and local keratin hyperplasia.