What will they do for you in the ER? As they evaluate your child, they should encourage you to hold him in your lap, remember to keep him calm. They might measure his blood oxygen level, with an oximeter or “pulse-ox.” This uses a small light source that is wrapped around a finger or toe and helps determine how your child is breathing. They might have you blow cool mist in front of your child’s face. If your child’s croup is severe enough (which is why you’re in the ER), they may give him vaporized Epinephrine to breathe with the cool mist. This works quickly to open the airways. Depending on the situation, the ER physician may recommend a short course of steroids. Don’t worry; this is not the “body-building” type of steroids. These will help keep the air passages open over the next few hours to days. Your child will only be on the steroids for a few days, there are no side effects to worry about when used for this short time. The first dose often needs to be given as an injection, since the child with severe breathing difficulty is in no mood to take an oral medication, or he may throw it up.
Dexamethasone has also been used during pregnancy as an off-label prenatal treatment for the symptoms of congenital adrenal hyperplasia (CAH) in female fetuses. CAH causes a variety of physical abnormalities, notably ambiguous genitalia in girls. Early prenatal CAH treatment has been shown to reduce some CAH symptoms, but it does not treat the underlying congenital disorder . This use is controversial: it is inadequately studied, only around one in ten of the foetuses of women treated are at risk of the condition, and serious adverse events have been documented.  Experimental use of dexamethasone in pregnancy for foetal CAH treatment was discontinued in Sweden when one in five cases suffered adverse events.