Are Head Lice Becoming Resistant to Medications?

I've heard that head lice are often immune to the usual treatments. Is that true? And what can parents do to get rid of lice for good?
- Keith

Just like the overuse of antibiotics has helped create so-called "superbugs," the ongoing use of lice treatments over the years has made the pesky parasites resistant to some treatment medications. The more people use the remedies, the more the bugs start to build immunity to them.

Researchers have been saying for years that this was probably happening. Although growing drug resistance can make getting rid of the tiny insects a real pain, it's not cause for too much concern. That's because lice are not dangerous. Lice don't cause any health problems or spread any diseases (unlike other bugs, such as ticks) — they're just an incredibly annoying problem for both parents and kids.

And the fact that lice sometimes don't respond to some of the treatments (like medicated over-the-counter and prescription shampoos, cream rinses, or lotions) doesn't mean that they don't ever work. They do, but it make time some time, patience, and working with your doctor to find the right one that finally gets rid of the little buggers.

Also, lice may linger if kids are still exposed to other infested children or if the medication isn't used exactly as directed. For example, parents might overlook the fine print about what not to do when using the medicines — like avoiding using a cream rinse or shampoo-conditioner combination before applying lice medication and not washing a child's hair for 1 to 2 days after using a medicated treatment.

Lice infestations are often over-diagnosed, too. Some parents who think a child has lice might be wrong — the itching and white specks could be caused by other things, like dandruff or ringworm of the scalp.

Even if there's no doubt that lice are the cause of all the scratching, it's important to avoid going overboard with treatments. Lice medications are insecticides and can be harmful when applied too heavily or too often. That means you should never use more than one head lice medication at a time, extra amounts of the medicine, or the same medication more than three times.

Be sure to talk to your doctor before treating — or re-treating — your youngster for lice. If the insects are still around 2 weeks after you started treatment or your child's scalp looks infected, call your doctor, who may recommend trying a different product.

And, as you're in the lice-fighting trenches, try to remember that this too shall pass!

Reviewed by: Steven Dowshen, MD
Date reviewed: January 2012

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