nix-shampooWhen they discover that their child is infested with head lice, many parents start looking for a tradename lotion treatment for head lice. One of them is Nix shampoo.

Is it effective at killing lice and their eggs? Is it safe to use on children? Most head lice shampoos claim to be effective and safe, and Nix has great product claims on their website, but let’s see if and how Nix lice treatment lives up to its promises.

What is Nix head lice treatment exactly and does it work?

Nix has an entire product line to remove head lice and their eggs, including head lice combs and a spray that claims to help preventing head lice. The main product is Nix Crème Rinse, which is what we commonly refer to as nix shampoo.

The active ingredient in Nix Crème Rinse is permethrin 1%. As permethrin is toxic to the nerves of adult head lice, it causes paralysis and death of these parasites. This is how Nix lice treatment can be effective.

There are many reports that the treatment didn’t work, and in many cases this is because it was not applied properly.

There are also studies and reports of resistance of head lice to permethrin in many western countries, which could be another reason why the treatment would not work.

The Nix official website states they are investigating this issue of resistance with experts and recommends not applying Nix shampoo more than twice if you see no results.

Anyway, note that Nix shampoo is only effective to kill adult head lice and nymphs (young lice), but does not work to kill nits, or head lice eggs. You’ll have to comb the nits out using a nit comb.

Is Nix safe to use?

Nix for head lice claims to be safe to use because it has been approved by the FDA (Food and Drug Administration) for children as young as 2 months.

Permethrin, the active ingredient in Nix lice treatment is a common synthetic chemical, widely used as an insecticide and insect repellent. It belongs to the family of synthetic chemicals called pyrethroids and functions as a neurotoxin.

Permethrin is used to eliminate head lice and mites responsible for scabies, as well as to prevent malaria in tropical areas.

Toxicity: Permethrin is known to be highly toxic to cats and fish and aquatic life, but not for humans or birds and is poorly absorbed by the skin.

Can permethrin cause cancer?: recently, the United States Environmental Protection Agency (EPA) has classified permethrin as “likely to be carcinogenic to humans” by ingestion.

But this rating is only based on studies in mice, and no human data were found on the carcinogenic effects of permethrin.

Thus the claim that Nix is safe is justified. However, this is true as long as you use the product properly, following exactly the directions of the manufacturer. And anyway you should always be careful and be aware of the following important points:

1) dermal exposure to permethrin may cause irritation, itching, or a prickly sensation where applied. This is why the product irritates so many children’s scalps. These symptoms however rarely last more than a day.
2) ingestion of permethrin may cause sore throat, abdominal pain, nausea, and vomiting.
3) inhalation of permethrin may cause headache, nasal and respiratory irritation, difficulty in breathing, dizziness, nausea or vomiting.

And always remember that the effects of permethrin on human health and the environment depend on how much permethrin you use and how long and frequent you apply the nix head lice treatment. The effects of the head lice shampoo also depend on the health of a person.

Nix official website:
A very in-depth factual sheet on permethrin can be found here: permethrin facts

Articles Related to Head Lice Treatments: