Lice: Facts & Fiction

Questions and answers about lice

Panic, confusion, anger, shame… lice seem to cause a lot more than just itching. Start by learning what is true and not true about lice and the treatment for lice treatment.

General Lice Questions

  • What Are Head Lice?

    Head lice are small insects (about 1/8 of an inch in size) that live and breed on the human scalp. They live approximately 40-50 days and go through three stages in their life cycle: eggs, nymphs and adults. They are about the size of sesame seeds, reddish brown in color, and can be detected by carefully inspecting the scalp with a magnifying glass and plenty of light. You should know that head lice are treatable, very rarely cause serious health problems, and don't warrant great concern.

  • What Should You Do If You Have Lice?

    Don't panic, head lice affect millions of people each year, especially school-age children. Head lice are treatable and are not known to carry diseases. If you are concerned about being "dirty" - contrary to popular belief, anyone can get head lice. You don't get head lice because of poor personal hygiene; in fact, head lice prefer clean hair.

  • What Do Head Lice & Nits Look Like?

    Head Lice are tiny reddish brown insects about the size of a sesame seed. Visible Nits (lice eggs) are tiny, whitish ovals. They are firmly glued to the hair shaft, most often near the scalp. Nits may be mistaken for dandruff but unlike dandruff, nits cannot be brushed off or removed by normal shampooing and washing.

  • Where Do Head Lice Come From?

    Anyone can get head lice – it has nothing to do with cleanliness or poor hygiene. Head lice are common among school-age children, particularly those in elementary schools. Head lice are transferred from one person to another through close physical contact or from sharing items like hats, combs, brushes, headphones, etc. For head lice prevention it is important to avoid sharing these items.

  • How Do You Get Head Lice?

    Head lice spread easily from person to person because they can survive away from the human body for approximately 48 hours, and nits can survive for up to 10 days. Lice are often spread by sharing hats, helmets, scarves, headphones, brushes, clothing and other personal items. Any objects that come in contact with an infested person can spread lice. Pets can be carriers but cannot become infested themselves.

  • What Are The Most Common Symptoms Of Head Lice?

    Since head lice need blood to live, their "stinging" of the scalp usually causes itching, which can lead to scabs or blood spots. Scratching behind the ears or the back of the neck is another possible sign. Because head lice generally feed at night, infected persons will experience the most discomfort and itching while trying to sleep. However, itching is not always present. You should also look for red marks on the scalp and neck. To most easily see nits check for them in natural light or a minimum of a 60-watt bulb light with a magnifying glass.

  • How Do Lice Grow?

    Female head lice lay approximately 8 eggs a day, which usually hatch in 7 to 14 days. Within their 23 – 30 day lifecycle they will lay up to 400 eggs.

  • What Is The Life Cycle Of Lice?

    Head lice begin their lives as eggs – empty eggs are called "nits" (The word "nitpicking" stems from the time-consuming process of going through a person's hair to remove head lice and their eggs). Eggs and nits are oval-shaped, tiny and reddish-brown, and attach to the hair near the root with a waterproof glue-like substance that cannot be washed out or blown away like dandruff. The female louse may lay over 100 eggs on the hair near the scalp. The eggs hatch in approximately seven to nine days and the nymphs begin feeding on blood through the scalp. Adult lice may live about three weeks or a bit longer. If the nits are found an inch or more from the scalp, the lice have probably hatched or are dead.

  • Can Head Lice Be Controlled?

    When head lice are removed from the scalp or hair, they usually die within a day or two. Similarly their eggs generally perish within a week when removed from the scalp or hair.

    Pets do not host or transmit human lice, and you should not be concerned about treating them. For lice prevention, other members of the household, however, shouldn't share personal items like combs, brushes, hats, towels, or bedding with anyone undergoing treatment. Any of these items that have been used by the one with lice should be disinfected.

    Bed linens, clothing, towels, and other items that have been used by an infested person should be washed in hot water and detergent, then dried on high heat and ironed. Combs and brushes should be boiled in water for two minutes or soaked in hot water (above 130°) for at least 10 minutes and then washed thoroughly with soap and water.

    Larger items, like couches and beds, can be treated with Nix Lice Control Spray.

  • Can Lice Fly?

    No, head lice are wingless insects that can't jump or fly, but they can crawl at a rate of 12 inches per minute.

  • Are Lice Only Found On Children?

    No, you can get lice at any age but it is most common for children between the ages of 5 and 12.

  • Do Lice Transmit Disease?

    No, Head lice are not known to carry disease

  • Do Pets Carry Lice?

    Head lice is exclusively a human disease, however, a louse can be transmitted to a pet that can transmit it back to the family. Head lice do not live off animals; they feed only on human blood.

  • Can Lice Survive Off The Body?

    Lice cannot survive for more than 48 hours away from a human scalp. Nits (lice eggs) can survive for up to 10 days but need a blood meal from a human one-hour after hatching. For that reason human head lice cannot survive for long periods of time on animals, but animals can be the carrier of the lice. For instance, if two children are playing with a dog, the dog can 'transport' the louse from one child to another.

  • How Can You Tell If Nits Are Alive Or Dead?

    Nits (lice eggs) are very small, so it is difficult to tell if a nit is alive or dead. Experts say empty eggshells are whitish in color while intact live eggs are reddish brown in color but since it is so difficult to tell, all nits dead or alive should be removed.

  • Will Nits Fall Out?

    Nits are fastened or cemented to the hair shaft. They will not fall off of the hair, as the hair grows the nits will grow out with it.

Treatment of Lice

Before you start head lice treatment

If you or a member of your household has head lice, please take a few moments to become familiar with the following information and directions before using Nix Crème Rinse to kill head lice.

  • How Does Nix Treatment for LiceWork?

    Lice treatments kill by acting on the central nervous system of the louse. Permethrin, the active ingredient in Nix Crème Rinse, is toxic to the nerves of head lice, causing paralysis and death of head lice. Don't panic if you see live lice, it may take up to several hours for lice to die. Remember to physically remove all nits (lice eggs) with the provided Nix comb as Nix Crème Rinse will not remove these alone.

  • Is Shaking Nix Treatment Product Necessary?

    Shaking is necessary. Nix Crème Rinse is an emulsion, which means that it consists of two phases which separate when left standing. The lice treatment product should be blended to form a consistent peach color prior to usage. If you do not perceive the product to be working, check with your health care professional to determine whether to retreat immediately or after seven days.

  • Should You Use the Entire Bottle of Nix?

    The success of Nix is based on using enough of the product to saturate the hair. You will want to wet the scalp from the roots to the end of the hair with Nix Crème Rinse. Hair length and thickness will determine the amount of Nix lice treatment needed.

  • When Do You Start Timing Nix?

    You will want to start timing with a watch or timer as soon as the hair is saturated with the product and the consumer has finished applying Nix Crème Rinse. Leave Nix Crème Rinse on the hair for a full 10 minutes, but no longer.

  • How Long Does Nix Remain on the hair?

    Some residual activity of Nix Crème Rinse remains on the hair for up to two weeks, even with regular shampooing. Only a small amount of residual Permethrin is removed each time the hair is shampooed.

  • Can Nix Be Used On People Without Head Lice?

    We cannot recommend Nix head lice treatment on people without head lice but since lice are transferable you should inspect every member of the house and if lice or nits are found you should treat that individual. Remember to thoroughly clean the house to prevent infestation. If you have further questions about using Nix head lice treatment in this way we would recommend that you go back to see the health care professional who originally advised treatment about this matter. The product is meant to be used in certain circumstances such as when there is a head lice epidemic which is identified by a health care professional who knows your specific medical history and is licensed to prescribe preventative use.

  • Are Head Lice Resistant to Treatment?

    There has been recent coverage in the media that head lice are becoming resistant to all pediculicides. We are consulting with experts in the industry for guidance in studying the issue. In the meantime, the best way to eliminate lice from your household is to follow the instructions for Nix head lice treatment and thoroughly clean head lice infested areas/objects in your home. We recommend that you seek the advice of your physician if after two Nix treatments you feel the product is not working.

  • How Many Treatments of Nix are Necessary?

    We recommend that you seek a physician's advice if you are having difficulty eliminating lice after repeated applications per label directions. Nix head lice treatment should not be used more than once every 7 days; if the 14 day Nix regimen is not working for you consult your doctor. (Our clinical tests indicate there is minimal skin absorption of Nix under labeled directions.)

  • Is It Difficult to Comb Nits (Lice Eggs) out of Hair?

    Unfortunately combing a child's hair can be a painful, long process. It may help to comb tangles from your child's hair with a regular comb first. Then try dividing the hair into sections prior to combing. If this still doesn't work you may want to consider purchasing a Nix metal comb which may be more durable at your local drug store.

  • Will Nits Hatch?

    No lice prevention product on the market will kill 100% of the lice eggs; however, with the residual left in the hair, any nits that are left will probably die shortly after hatching. We always recommend removing all of the nits (lice eggs) to most effectively remove lice.

  • Can Nix Be Used On Pubic Lice?

    No, Nix cannot be used to treat pubic (crab) lice. There are other OTC products on the market that are labeled for this indication.

  • What Should Be Done If New Nits (Lice Eggs) Are Discovered?

    As you have probably seen it is very difficult to distinguish if nits are alive or dead but regardless you will want to remove them and do not retreat unless it is 7 days or more after the initial head lice treatment. (It is very important to re-clean the environment if new nits are discovered on a person's head.)

  • Can Vinegar Be Used With Nix To Remove Nit (Lice Eggs)?

    Although vinegar has not been studied with Nix, if you are going to use another head lice treatment product it should be used well in advance and prior to saturating the hair with Nix to help prevent interference with the residual Nix.

Prevention of Lice

  • How can you prevent Head lice?

    The best way to prevent Head lice is to make sure your child is careful about sharing any personal items with his/her siblings, classmates, and friends – especially brushes, hats, pillows, headphones and sports headgear.

  • How can you clean the environment from new Lice?

    If lice are seen before 7 days, they are probably hatched nymphs which should die due to the residual left on the hair. Any lice or nits seen after head lice treatment should be removed by thoroughly combing. The environment should be treated at the same time Nix is applied. However, just as you are continuously removing nits and live lice from the hair, remember it is important to re-clean the environment.

  • Should you vacuum after you use Lice Spray?

    Louse sprays are typically designed for bedding and furniture, and recommended for use on objects that cannot be laundered or dry-cleaned. For lice prevention, even if you use a spray, we advise thorough vacuuming and then putting the vacuum bag in a plastic bag and discarding it.

Nix Lice Product Information

  • Can other products be used with Nix?

    We would recommend seeking the advice of a physician since we have no specific information on another company's product.

  • Is Nix toxic?

    Please refer to Safety Call International –

  • How long do the residual effects of Nix Head Lice Treatment remain on the hair?

    The residual activity of Nix head lice treatment remains on the hair for up to 14 days and should prevent re-infestation.

  • What storage temperature is recommended for Nix Lice Treatment Products?

    The label indicates 59–77 degrees Fahrenheit.

  • Can you use Nix after expiration date?

    We do not recommend using expired Nix lice treatment product since it may not be as effective. If already used, the lice treatment product should not be harmful. You should wait the full 7 days before reapplying however since the active ingredients may not have broken down entirely.

  • What is the Nix Warranty?

    Your Satisfaction is 100% Guaranteed. Our warranty states "If you are not satisfied with Nix lice treatment, we will refund your purchase price."

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