Head lice…ugh, right?  This is for all the folks out there with children ages 2 – 13!  Not that it’s impossible for people of all ages to get head lice, but a majority of the cases fall in this age group.

We may be past the prime head lice time, the back-to-school months, but no doubt the little buggers are still out there fighting to keep their place among the young children of the world.  Head lice are highly contagious, affecting millions of children between the ages of 3 and 13 annually.  Not to mention they can be downright annoying and the bane of many parents existence!  So, what is a good option for the treatment of head lice?  According to the American Academy of Pediatrics (AAP), over-the-counter Nix Cream Rinse (permethrin 1%) is a first-line treatment.

Permethrin 1% cream rinse was originally available by prescription only, but in 1991, the FDA reclassified it as a nonprescription medication.  It was introduced to the OTC market as Nix Cream Rinse, and since then has been one of the most popular products purchased for the treatment of head lice.

Permethrin 1% cream rinse is indicated for the treatment of head lice only.  The medication is not very effective in killing pubic lice, and the prescription strength permethrin (5% cream) is what is needed to kill off scabies.

The only time you wouldn’t head straight for the OTC permethrin 1% cream rinse to treat your child’s case of head lice is when resistance is suspected, a growing problem in many communities!

How the drug works

Permethrin 1% is included in the class of medications called the pyrethroids, which are neurotoxic to head lice.  Permethrin acts on the nerve cell membrane of lice by disrupting certain essential components, leading to paralysis of the parasite.  The product will kill living lice, but re-application is almost always recommended because newly laid eggs do not develop a nervous system for several days.  No nervous system, no paralysis!

Side effects and precautions

Permethrin is well-tolerated by people of all ages.  We’re talking about a medication that has such a low toxicity profile that it can be used to treat head lice in children as young as 2 months of age!

Your child may complain of an itchy, burning, stinging and irritated scalp, but even these adverse effects will subside after a short amount of time.  Also, you definitely do not have to worry about the cream reaching high levels in your child’s body because it is estimated that less than 2% gets absorbed through the skin.

The other pyrethroid

Pyrethrins are similar to permethrin and are also available over-the-counter.  The two medications’ side effect profiles are virtually the same, and there is no significant difference in efficacy between the two when treatment consists of two applications.  However, permethrin is more effective than pyrethrins when just one application is used.

You would choose permethrin over pyrethrins if your child has an allergy to ragweed or chrysanthemums as pyrethrins have the potential for cross-sensitivity in children with these plant allergies.

Administration guidelines

When it comes to treating head lice, there’s nothing more important than administering the medication correctly.  Always follow the package instructions completely in order to ensure a successful treatment.

With permethrin 1% cream rinse, you would first shampoo your child’s hair with regular shampoo, rinse, and then towel dry.  Next, you would apply a sufficient amount of cream rinse, enough to wet the child’s hair and scalp.  The hardest part may be getting your child to sit still long enough to let the cream rinse do its job –the permethrin has to remain in the hair for 10 minutes!  After the 10 minutes is up, rinse the medication out and towel dry the hair.  You would want to use a fine-toothed comb at this point to remove the dead lice and nits (eggs).

Fantastic, the treatment process must be complete after all this, right?  Not so fast because according to the AAP, a re-application of the permethrin 1% cream rinse should be done in nine days.  Until recently, the second application was done in seven days, but upon further examination, the nine day rule made more sense.  This is because on average, it takes an egg eight to nine days to hatch.  If the second application is done at seven days, most of the eggs would not have hatched yet.  The medication will kill living lice, but not have much of an affect on the eggs.

Recommendations

So, we have figured out that OTC permethrin 1% cream rinse should be on the top of your list when trying to determine where to start when treating your child’s head lice, but what happens if the lice are not gone even after doing two rounds of applications?  Surprisingly enough, it is recommended that we use a third application to help eradicate the lice.  If we still have live lice around after all of this, we can assume the treatment has failed or resistance exists.  At this point, you would want to take your child to their physician to go over their prescription medication options.  There are several effective prescription medications to pick from, so arm yourself with information on how to prevent the lice from coming back and your child should be good to go in no time!

Thanks for checking in.  If you have any questions, don’t hesitate to contact me at Cate@getpharmacyadvice.com.

Happy Thanksgiving a little early!