Dear Doctor Column, June 8, 2009

First Aid that Can Cause More Harm than Healing

Question:

Should I use hydrogen peroxide and Neosporin on cuts and scrapes? If not, what is the best first aid for a minor skin wound?

Answer:

Many over-the-counter antiseptics and wound cleaners are unnecessary, and some even may be harmful. Hydrogen peroxide is a good example. It is not a good cleansing agent, as many people mistakenly believe, and can damage the outer layer of skin and slow healing. Antibiotic ointments like Neosporin do encourage healing of minor wounds but can cause allergic reactions and skin irritation in some people. Neosporin’s main ingredient neomycin is an irritant for many people. Bacitracin, which is in many ointments, also can cause burning, redness, and rash. To achieve a similar sealing effect and help prevent germs getting in a wound, experts say to use Vaseline.

The easy availability of the over-the-counter antibacterial ointments may tempt you to try to treat an infected wound, such as a bacterial skin infection, boils, folliculitis, or impetigo, but your doctor needs to handle these infections.

Other options you are better off without:

• Rubbing alcohol will kill microbes, but it damages and dehydrates skin. Do not pour rubbing alcohol on a wound. Do use it to clean a needle, tweezers, or to clean undamaged skin before a shot, for example. (Let the alcohol dry to achieve its microbial effect.)
• Iodine irritates skin and slows healing.
• Betadine slows healing.
• Benzalkonium chloride and chlorhexidine are not very useful. Soap inactivates benzalkonium. Chlorhexidine can increase inflammation if used in high concentrations and cannot be used near eyes and ears.
• Hexylresorcinol and hexachlorophene kill microbes but may damage skin. Hexachlorophene is available by prescription as PhisoHex. Use this cleanser only as directed.
• Silver nitrate and colloidal silver have not been ruled safe or effective for wound care by the FDA. Avoid products claiming that silver has antibacterial properties.
• Mercurochrome or Merthiolate: These contain mercury and were banned about a decade ago. If you come across them in an old first aid kit or medicine cabinet, throw them away.

Minor wounds only require cleaning with soap and water to avoid infection. Some wounds need only gentle swabbing with a clean wet cloth; other wounds benefit from holding under cool running water. An elbow or knee scraped against pavement, for example, can be washed with tap water under enough pressure to thoroughly cleanse the wound of debris. Restrict soap to cleaning the surrounding skin because it may irritate the wound itself. Make sure you wash your hands with soap or antibacterial cleanser before and after cleansing the wound.

If dirt or debris are in the wound after washing, use tweezers (cleaned with alcohol) to remove particles. Don’t probe or dig around to remove debris. A doctor should remove debris still embedded in the wound after cleaning.

Cover the wound with a bandage to keep it clean and prevent contact with harmful bacteria. When the wound heals enough that infection is unlikely, you can expose it to air to speed wound healing. Keep in mind that some people are allergic to the adhesive used in bandages. If this is the case, you can use adhesive-free bandages or sterile gauze held in place with paper tape to cover the wound.

Doctors recommend you get a tetanus shot every 10 years. If your wound is deep or dirty and your last shot was more than 5 years ago, he or she may recommend a tetanus shot booster.

Some wounds lead to infection more easily that others, such as animal or human bites, punctures, crushing injuries, dirty wounds, wounds on the feet, and wounds that are not promptly treated.

Call your doctor if:

• The wound is large or deep, even it does not bleed very much.
• The wound is more than a quarter inch deep or reaches bone. It may need stitches.
• The wound is a human or animal bite.
• The wound seems to take a long time to heal.
• A fishhook or rusty object caused the wound.
• Debris or an object is embedded in the wound after cleaning.
• The wound is warm, red around the edges, is painful or throbbing, swollen, or has pus-like drainage.
• You have not had a tetanus shot in the last 10 years.