Boric acid is a weakly acidic inorganic compound with antibacterial, antiseptic, and astringent properties. It is commonly used for skin disinfection, eye rinsing, and in industrial applications. However, it should be avoided for long-term, large-area use, accidental ingestion, or contact with mucous membranes.
1. Disinfection and Antibacterial Effects: Boric acid solution can be used for disinfection of superficial skin wounds, inhibiting bacteria and fungi. A 3% concentration of boric acid aqueous solution is suitable for wet compresses on exudative skin lesions such as eczema and dermatitis, reducing exudation and relieving itching. Strict dilution ratio must be followed during preparation to avoid skin irritation from high concentrations.
2. Eye Irrigation: Diluted boric acid solution can be used for rinsing conjunctivitis or foreign bodies in the eyes, helping to clean the conjunctival sac. However, the concentration must be controlled below 2%, and a second rinse with physiological saline should be performed immediately afterward. Contraindicated in patients with corneal injuries, as it may delay wound healing.
3. Industrial Applications: Boric acid plays an important role in glass manufacturing, ceramic glaze production, and flame retardant production. Industrial-grade boric acid contains more impurities and cannot replace pharmaceutical-grade products. Protective equipment must be worn during handling to prevent inhalation of dust and respiratory irritation.
4. Gynecological Adjunctive Use: Boric acid suppositories have been used to treat candidal vaginitis by altering vaginal pH to inhibit fungi. Due to its potential toxicity, it has been gradually replaced by safer antifungal drugs. Pregnant women and women during menstruation should not use it.
5. Household Moth Control: Boric acid powder can be used as an insecticide for pests such as cockroaches, working by destroying the insect's exoskeleton. Keep out of reach of children and pets. Ingestion may cause vomiting, diarrhea, and other symptoms of poisoning, and in severe cases, kidney damage.
Avoid using boric acid preparations on broken skin and mucous membranes. Children should use it under adult supervision. Discontinue use immediately if allergic reactions such as skin redness, swelling, or burning occur. Industrial users are advised to have their kidney function checked regularly; long-term, high-dose exposure may affect fertility. Store in the home separately from food to avoid accidental use. Medical boric acid solutions should be prepared and used immediately; prolonged storage may cause crystals to precipitate and irritate tissues.
