Will Hair Dye or Bleach Kill Head Lice?

Many clients ask us if they can color their hair to treat head lice or insist that their routine hair appointments would kill any lice if they were to get it. This is a common misconception and although hair dye and bleach may contain strong chemicals it is not strong enough to kill head lice.

What happens if you dye/color your hair when you have lice?

Although hair dye may drastically change the look of your hair and contain strong chemicals, it won’t be able to kill head lice.

Because most people often have lice for at least a few weeks before discovering it, they often go about their normal activities including coloring their hair before being treated for lice. We see this often and from our observations, the dye doesn’t kill the lice and colors them with the hair. If someone dyes their hair pink the lice and nits will be pink. The hair dye also won’t suffocate the lice because they are able to shut their bodies down for up to 18 hours while hair dye is usually only left on for about 45 minutes.

What happens if you bleach your hair when you have lice?

blonde woman
Achieving bright blonde hair often requires the use of strong chemicals but unfortunately  bleach doesn’t kill head lice either.

The main component in hair bleach is hydrogen peroxide which is not known to kill head lice. Bleach is also typically not left on the hair for very long. If a heat dryer is used during the bleaching process the extreme temperature could kill some of the lice and nits but it is unlikely that it would kill an entire infestation.

Can you dry or straighten your hair to kill lice?

The heat from a blow dryer can kill some of the lice, but you will probably burn yourself before killing the entire infestation.

Head lice cannot survive extreme temperatures including high heat which leads many of our clients to ask if using heat on their hair will kill lice. The heat can kill the lice but in most cases it won’t kill all of it. With a hair straightener you are not getting all the way to the scalp with the heat so you may burn some of the nits this way but you won’t be able to reach the actual lice. The heat from a blow dryer will reach the scalp but you are likely to burn your scalp trying to kill the lice this way before you are able to get all of them. Using any kind of heat will also cause the nits to crystallize, which means they have melted onto the hair strand. This means the nit is dead but it is still in the hair and is harder to remove even with a lice comb.

Closing Notes

While some of these methods can potentially kill some head lice, none of these things are recommended as a way to treat head lice. Going to a professional or using an all natural treatment kit is a much safer and easier route to treat lice. Coloring or bleaching hair can cause permanent damage especially if done in combination with using chemical lice treatments and combing the hair. Using high heat can burn your scalp and cause heat damage to your hair. Using a fine lice comb will always be the best way to treat an infestation.