Are Head Lice Becoming Resistant to Medications?

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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 head lice resistant to some treatments. The more people use the remedies, the more the pesky parasites 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 lice a real pain, it's not cause for too much concern. That's because lice are not dangerous. They don't 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 those treatments don't ever work. They do, but it may take 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 medicine isn't used exactly as directed. For example, parents might overlook the fine print about what not to do when using the medicines. You should not use a conditioner or shampoo-conditioner combination before applying lice medication. And do not re-wash the 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 medicine at a time, extra amounts of the medicine, or the same medicine 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: Larissa Hirsch, MD
Date reviewed: April 2015

Related Resources

OrganizationAmerican Academy of Pediatrics (AAP) The AAP is committed to the health and well-being of infants, adolescents, and young adults. The website offers news articles and tips on health for families.
Web SiteHeadLice.Org for Kids This site, run by the National Pediculosis Association, is designed to help kids understand lice. It has games, animation, and frequently asked questions about lice.

Related Articles

First Aid: Head Lice Lice commonly spread from kid to kid. They're not dangerous - but they are creepy and annoying. Here's what to do about them.
Pubic Lice Pubic lice are six-legged creatures that infest the hair in the pubic area. Pubic lice infestation is considered a sexually transmitted disease (STD), but it can be contracted in other ways.
Head Lice Lice aren't dangerous and they don't spread disease, but they are contagious, annoying, and sometimes hard to get rid of. Learn more about this common childhood problem and how to get rid of those pesky little bugs.

Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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