When Will Hydrocortisone Help A Rash?

Got an itch that needs to be scratched? Before you go rubbing it raw, you might try to appease the annoying tingling by reaching for a bottle of hydrocortisone. But as dermatologists can attest, not all rashes benefit from the over-the-counter cream.

Hydrocortisone, a topical steroid, is made for treating “localized inflammatory reactions,” which are basically rashes that result from a hyperactive immune system response. For example, it can work magic on skin conditions like eczema, dermatitis, psoriasis, insect bites and poison ivy. After all, it’s a medicine cabinet staple because it’s so versatile. 

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“For a mild rash, it can take down the redness and make it go away,” says derm Dr. Elissa Lunder. “But honestly, so many people just use it the wrong way.”

That’s because it often gets slathered on to combat itchiness, but that symptom is not always a sign that it will work. In fact, it’s a common reason for misuse: “For instance, athlete’s foot and hives can be itchy, but a steroid won’t help,” she explains. 

Dermatologist Dr. Adarsh Mudgil, a professor at the Mount Sinai School of Medicine, also warns that hydrocortisone won’t work on fungal, bacterial, or viral types of rashes, and sometimes, can even make a bad situation worse. “Usually when [hydrocortisone] doesn’t work is when they come see us,” he says.

Luckily, OTC hydrocortisone is mild, so if you do decide to give it a whirl, the stakes aren’t too high. That said, Dr. Lunder recommends using the ointment variety over the cream for better results, and no matter what you choose, “The stuff you’re getting over-the-counter is essentially one notch stronger than a moisturizer,” Dr. Mudgil points out. “[What we can] prescribe comes one-thousand times more potent.”

Just remember that if you’re going to use the gentle 1 percent kind from your local pharmacy, there are three crucial factors to keep in mind: duration, location and the amount.

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“The main danger with steroids is that you’ll overuse them. Long-term risks vary: They can cause stretch marks or a permanent thinning of the skin—and that stuff is not reversible. So, a steroid is not a moisturizer,” Dr. Lunder warns.

But the duration of use truly depends on the location. According to Lunder, you shouldn’t use hydrocortisone more than twice a day for two weeks. On your eyelids, face, or neck, that number drops sharply to a max of three to five days.

“You really don’t want to use it on your face, your neck, your eyelids, your vagina, your groin, or your armpits, without talking to a doctor. That’s where you run into problems,” Lunder advises. For example, overusing steroids on the eyelids can be a risk factor for glaucoma. Additionally, less is more, she advises. “It gets absorbed into the skin quickly.”

And since it’s fast acting, never cover it up with plastic wrap or a Band-Aid. By putting it under occlusion, “You’re actually increasing the potency. So, that’s a big no-no,” says Dr. Lunder.

The bottom line: Unless it’s a condition you’ve had before, it’s nearly impossible to diagnose yourself; (i.e. the same problem can have a variety of appearances because everyone’s skin is different). “It’s even tough sometimes for a dermatologist to tell what it is just by looking at it,” Dr. Mudgil admits. So whatever you do, don’t act rashly (pun intended) and do a Google image search to figure out what is on your skin. It’s more likely to cause anxiety than an honest assessment.

Lastly, if you are using hydrocortisone and don’t see any improvement after a few days, (or heaven forbid it gets worse), don’t hesitate to consult a professional. “If something is just not going away, then you should see a doctor,” Dr. Lunder concludes. And in that case, you’ll be saving your own skin—literally!

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