Do antibacterial products promote or impede skin health?

February 3, 2010

The current H1N1 influenza scare has hand sanitizers popping up everywhere - hotel lobbies, airports, day care centers, schools, hospital waiting rooms, office elevators and public restrooms. You can hardly enter any public building without having to sanitize your hands with this clear, alcohol-smelling liquid that turns your skin to a dry, itchy, flaky mess.

Key Points

Certainly, the H1N1 epidemic did not reach the proportions predicted, and perhaps this was due to the mass use of hand sanitizers and increased public hygiene. Once spring rolls around, the flu season will pass for another year, but I wonder if hand sanitizers will also be put away for another year, or left in place as a cornerstone of public health. This is an interesting question to ponder, as key to determining the value of constant alcohol and antibacterial use is an understanding of what constitutes the normal human hand flora and how this relates to skin health.

Disease eradication

Many diseases, such as cholera and hepatitis A, have been almost eradicated in the United States, while many in Third World countries still die because of unsanitary drinking water. One of the main routes for disease transmission is from the hands to the mouth, nose or eyes. Is soap and water sufficient, or are antibacterial products necessary to prevent disease transmission and improve skin health?

Topic of triclosan

The development of triclosan was a major step forward in the evolution of cleansers, and it led to the advent of deodorant soap. All deodorant soaps and hand sanitizers contain triclosan, which has broad-spectrum effects against both gram-positive and gram-negative bacteria. Even though triclosan was determined to be a potent antibacterial, its mechanism of action was unknown for years.

Many scientists said triclosan was so effective that it was impossible for bacterial resistance to occur, which led to widespread use of the agent without concern. As it turns out, triclosan works by interfering with bacterial cell wall synthesis, and, indeed, bacteria have - and will - mutate to overcome cell wall synthesis inhibition.

The concern over resistance to triclosan was forgotten until several years ago, when scientists at Procter & Gamble developed a bacterial strain that was triclosan-resistant. However, this strain was short-lived and existed only in the laboratory. To date, no bacteria with triclosan resistance have been found in the general population.

Remember, triclosan is used in many surgical scrubs and for industrial disinfection. Loss of this topical antibacterial would create huge healthcare problems. Even the Food and Drug Administration was concerned about triclosan resistance and briefly looked into the issue several years ago, but implemented no regulation regarding the use of the agent.

Should dermatology be concerned over the mass use of triclosan? Does skin sanitation with triclosan promote skin health? In order to answer these questions, we must first determine what constitutes healthy skin when it comes to the presence or absence of bacteria.

Biofilm health

These days, we're gaining a better understanding of what is present in the skin biofilm. We know that the biofilm is very important in keeping the skin healthy and that many skin diseases arise from biofilm issues. Changes in biofilm cathelicidin levels may precipitate rosacea; the presence of increased biofilm Staphylococcus aureus may precipitate atopic dermatitis; and the finding of pathogenic strep organisms in the biofilm may precipitate impetigo.

These biofilm changes may lead to disease, but what about the "normal" organisms in the biofilm that maintain proper skin balance? What constitutes these "normal" organisms, and how many of them should be present along with other substances to keep the skin healthy?

These questions remain unanswered, and dermatologists need to investigate them. So, until the answer is forthcoming, what should dermatologists say to their patients who wonder if they should use hand sanitizers on a daily basis? Do skin sanitizers promote skin health? Or are we leaving ourselves open for other, more serious, problems?

Dermatitis woes

There can be no doubt that the epidemic of hand dermatitis I am treating this winter is due to the widespread frequent use of hand sanitizers. I recommend to my patients that they use hand sanitizers if they have a sick family member with a contagious disease or if they are going into a hospital or nursing home or other environment in which they might encounter contagious disease. However, if the antibacterial is not needed, it should not be used.

I think it is key that we use triclosan where benefit can be achieved, but avoid the widespread use of triclosan when the benefit is unclear. Skin health represents a symbiosis between humans and the contaminated world in which we live. The careful balance must be maintained.

Zoe Diana Draelos, M.D., is a Dermatology Times editorial adviser and consulting professor of dermatology, Duke University School of Medicine, Durham, N.C. Questions may be submitted via e-mail to zdraelos@northstate.net