The day after Nikki Fisher’s son was born, her midwives pointed out that his legs and tummy had a few red, textured spots on it, and called it a newborn rash, or erythema toxicum. “He didn’t seem bothered by it,” she says, adding that the midwives said it was fairly common, and she should just keep an eye on it.
Approximately 50 percent of full-term newborns develop erythema toxicum neonatorum, a common newborn rash, says Carmen Liy Wong, a paediatric dermatologist at the Children’s Hospital of Eastern Ontario in Ottawa.
First off, it’s not toxic at all, clarifies Wong. It sounds much scarier than it is, so if your doctor diagnoses this skin condition, don’t panic. It’s a very common reddish rash that appears on newborns and it’s harmless, she explains. It usually appears within the first week of the baby’s life and goes away again within one to two weeks. It generally shows up on the baby’s face and torso but it can also, more rarely, appear on their arms and legs. Though it normally starts within the first week of the baby’s life it can happen later, even up to four weeks after they are born.
This rash usually shows up as little raised red lesions filled with whitish or yellowish pus. There can be lots of spots (or just a few) differing in size with undefined borders. If you press the spots they will blanch or turn white. The rash can look similar to flea bites, says Wong, and doctors don’t know what causes it. Even though there’s pus, it’s not an infection, so it’s not dangerous, she explains. “The way my midwife explained it was that it's just sort of their skin adapting to the outside world and different materials,” says Fisher of her newborn’s rash.
There’s no specific treatment for erythema toxicum, but Wong recommends a short daily bath to clean off any spit up, sweat or poop explosions and to help keep the skin clean so it can heal. (Wait until after the first 24 hours after birth because studies have shown that waiting can improve the skin’s condition by allowing it time to absorb nutrients from the vernix, that gooey coating covering your baby at birth.)
Keep the water lukewarm and make sure the bath is less than 10 minutes. “Baby’s skin is very fragile and very thin so over-washing may damage the skin,” says Wong. And skip any fragranced or harsh soaps. Babies’ skin is sensitive so it’s important to use hypoallergenic products that are mild and fragrance-free. Then, follow the bath with a light moisturizer that’s also fragrance-free. Don’t slather anything thick or occlusive like petroleum jelly on a newborn or you might actually make their rash worse by trapping heat or bacteria. Baby’s bodies can’t regulate their temperatures properly yet so they often end up with heat rash in addition to the erythema toxicum. Speaking of heat, don’t overdress your baby or it can also make the erythema toxicum worse (and lead to a heat rash as well). And though it’s tempting, don’t pick at the baby’s rash—you could cause an open sore which is more prone to secondary infection, says Wong.
The newborn rash can be confused with baby acne, also known as milia. Baby acne looks similar to teen or adult pimples and it generally only occurs on the baby’s face. Baby acne can occur in the first few months of life. But baby acne usually lasts longer than erythema toxicum, says Wong. Heat rash can also look similar because, as mentioned, babies can’t properly regulate their temperature yet and because of this it’s also quite common in newborns. If you don’t wash the baby for several days they may develop a heat rash, usually in areas that are covered by clothing where the sweat glands get clogged. Heat rash can feel irritating for the baby, so stick with a daily bath to help keep their skin regulated and clean. Both of these skin conditions are also not serious, says Wong.
The rash should resolve itself within a week. But it can come back within the first six weeks of your baby’s life, so if it does, don’t be alarmed. If it does, the recurrence should be milder. There are no long-term issues associated with the rash either, says Wong. Fisher said that it took about a week and a half for her son’s rash to fully go away and it hasn’t come back.
“Usually the [newborn] rash is completely asymptomatic,” says Wong. But if the baby has a fever, the rash is really red, it spreads across the baby’s body, or your baby is irritable or not acting like themselves, it’s time to go see your doctor. This could mean you’re dealing with something other than erythema toxicum. Also, if the rash looks infected, it’s also time to seek medical help.