What kills bacteria on skin?

What kills bacteria on skin includes your body's natural defenses and various topical antimicrobial agents that are safe for skin use. Naturally, your skin has antimicrobial peptides like defensins and cathelicidins, and beneficial bacteria that compete with harmful bacteria, plus slightly acidic pH that inhibits growth. For external killing, common effective agents include soap and water which removes bacteria by surfactant action and rinsing, reducing counts by 90 percent, 60 to 70 percent alcohol based hand sanitizers which kill most bacteria quickly by denaturing proteins, chlorhexidine gluconate used in hospitals for surgical scrub which kills bacteria and has residual activity, povidone-iodine which kills bacteria, fungi, and some spores, and benzoyl peroxide used for acne which kills Cutibacterium acnes. Hydrogen peroxide at 3 percent kills bacteria but can also damage healing tissue if overused. For minor cuts, cleaning with soap and water then applying antibiotic ointment like bacitracin helps. For overall skin hygiene, regular washing with mild soap, not over-washing which damages skin barrier, keeps bacterial load low. Good indoor air quality with HEPA filtration reduces airborne bacteria that settle on skin. Avoid harsh bleach or undiluted vinegar on skin as they irritate and damage barrier. If you have signs of bacterial skin infection like increasing redness, warmth, swelling, pus, or fever, see a doctor as you may need prescription antibiotics, as topical killing alone may not reach deeper infection.