Krafchik: In general, babies handle diapers extremely well. Some people prefer to use an emollient like petrolatum on the skin. I don't think that is needed unless there is diaper dermatitis. My advice is to dampen a washcloth, gently wash the area, and then pat it dry during changing. When putting on the new diaper, you can either leave that area dry or apply a small amount of petrolatum.
Leyden: I agree that most babies do very well without special treatment. There's a general tendency for mothers and their doctors to think that infant skin is more vulnerable, but there's a lot of evidence to the contrary. In the absence of eczema, psoriasis, or a chronic rash, the skin of infants is actually quite hardy. In fact, you might say, "It's healthier because it's newer."
Krafchik: That's right. It's quite resistant naturally.
Leyden: It's quite capable of taking care of itself. So gentle cleansing is all you need. The technology of cleansing materials has also changed over the past 15 years. Detergents have become much more skin friendly, and infant wipes are milder as well.
Spraker: Dr. Leyden, do you think the diaper area needs to be washed after every change as Dr. Krafchik suggested? There have been studies showing that urine is not irritating, which would imply there's no need to wash the diaper area unless there's fecal soiling.
Leyden: I don't think you have to. But if you would like to, there are materials available now that allow you to do so without causing harm.
Schuman: How do you dermatologists feel about the propylene glycol that's included in some but not all of these cleansing products?
Leyden: Propylene glycol is innocuous until you get up to certain concentrations. It has to be around 10% before you can begin to show an irritant potential, and that's with exaggerated exposure. If it's in the 30% range, then it can definitely cause irritation.
Spraker: What about powders? My view is that they're not necessary because the inner layer of a disposable diaper is so smooth that the powder doesn't help reduce friction.
Leyden: That's right, but if you want to use a powder, cornstarch is preferable.
Schuman: Yes. It used to be thought that cornstarch would encourage the growth of Candida, but that's been disproven.
Krafchik: I prefer not to use powder because it can mix with urine to become pasty and irritating.
Leyden: That's true for most powders, but not cornstarch. I once did a one-year project for the Army, which had an interest in friction. We looked at different powders and different ways of inducing friction, and we found that talcum powder intensified frictional forces on wet skin but that cornstarch reduced friction. Later I ran across an article in the lay press about long-distance bicycle riders who had found empirically that the best way to prevent erosions and irritations on their buttocks was to use cornstarch. Also, talc is dangerous. If accidentally aspirated by the infant it can cause pneumonitis.
Krafchik: Zinc is another ingredient used on skin, and some people think it has healing qualities. I've always thought of zinc oxide as an emollient. Does zinc have any medicinal qualities? Does it help in cases of dermatitis?
Leyden: It's difficult to study wound healing because there are so many variables that can't be controlled. But zinc is an interesting material that is found in a lot of systems and that has many possible effects. Probably zinc oxide has worked because it was a little more protective than petrolatum. It has antimicrobial effects at high enough concentrations.
Spraker: Dr. Schuman, as a pediatrician, how do you approach treating acute diaper dermatitis?
Schuman: The treatment varies with the appearance of the rash and the perceived cause. Irritant dermatitis is the most common variety I see, and one can argue that with mild cases you don't necessarily have to treat. Usually only a barrier paste or ointment or a mild steroid such as hydrocortisone is indicated. For Candida dermatitis, I prescribe a topical antifungal. Appropriate cleansing is also important when feces are present. And it's important that the diaper be changed as soon as possible after fecal soiling. We need to keep in mind that there are kinds of dermatitis associated with eczema, zinc deficiency, and other causes. So redness in the diaper area may not be just an irritant or Candida dermatitis.