Frequently Asked Questions

Knowledge is power. And getting the facts about lice can be an important way to enhance your understanding during the treatment process. The following is a list of common questions that will provide you with the lice facts you need.

General head lice FAQs and information about lice

The most common symptom of lice infestation is itching. However, infestation may continue even after itching stops.With a first case of head lice, itching may not develop for 4 to 6 weeks. In addition, infestation may be present even if there is no itching. Some children experience no symptoms. Never initiate treatment unless there is a clear diagnosis of head lice.

Head lice are tiny, wingless insects that live on the human scalp. They are about as big as sesame seeds. Lice eggs(nits) are about the size of poppy seeds and are difficult to see because their color easily blends in with the infested child's hair. Eggs are laid near the root of the hair and are attached with a glue-like substance that can't be washed or blown away.

Once lice have hatched from eggs, they leave empty eggshells behind called "nits". Nits vary in color—from yellowish-brown to white.

We have illustrations and details in the section called How to Recognize Lice on this site.

No. The types of lice that infest humans do not live on pets or other animals. There are other types of lice that live on animals, but these lice do not infest humans. If there is a concern that an animal may have lice, please refer to a vet for additional information. RID® is not approved for use on animals.

Head lice live approximately 40-50 days and go through 3 stages in their life cycle:

Egg Stage: The adult female louse lays the egg with a special glue that cements it to the hair shaft near the root. The eggs develop and hatch approximately 10 days later.

Nymph Stage: Once the louse hatches, it is called a nymph and is barely visible to the naked eye. The nymph cannot reproduce because it is not fully developed. After about 12 days, it becomes an adult.

Adult Stage: The adult female louse can lay up to 10 eggs a day—starting another generation of lice. The adult stage lasts about 30 days.

Head lice usually survive for less than one day away from the scalp at room temperature according to the American Academy of Pediatrics.

The most common way of getting head lice is through head-to-head contact. Lice cannot fly or jump but they can crawl very quickly. Infestation can be spread by head-to-head contact with another infested person or by sharing personal items. To prevent infestation from spreading, DON'T allow head-to-head contact and DON'T share or borrow hair items (e.g., combs, headbands, etc.), headgear (e.g., hats, headphones, etc.), or other personal items.

Head lice seek warm temperatures, so they stay close to the scalp. Head lice are parasites that feed by piercing the scalp and sucking blood. The scalp often becomes itchy when the infested person has developed an allergic reaction to this feeding.

There are 3 kinds of lice which infest humans: (1) head lice, (2) pubic lice (crabs) and (3) body lice. The most commonly reported infestation is head lice.

General head lice treatment and prevention FAQs

Head lice can be passed from one child to another, usually by head-to-head contact. Also, make sure your child doesn't do the following:

  • Share or borrow combs, brushes, barrettes, hair ribbons, headbands, or other personal items
  • Share or borrow hats, sweaters, coats, scarves, helmets, headphones, pillows, or stuffed animals

Carefully inspect your child daily for at least 2 weeks after the second shampoo treatment is complete. If you see lice or eggs, consult your doctor.

Check other family members for head lice. If anyone in the family is infested, treat them by following the RID complete elimination process.

Be sure to repeat both Step 1: Shampoo and Step 2: Comb-out 7-10 days after first applying RID Lice Killing Shampoo.

Head lice treatments, such as the RID® Lice Elimination Complete Kit, can be found in your favorite store in the First Aid or Shampoo aisle.

The patented RID® Lice comb is meant to be reused. To disinfect, soak it and any other combs and brushes in hot water above 130 degrees Farenheit for at least 10 minutes.

To eliminate lice, the child or infested person(s) should be treated with a lice-killing shampoo, like RID® Lice Killing Shampoo, which is proven effective when used as directed*. After shampooing, combing is an essential step to remove lice, eggs, and nits.

According to the CDC, children diagnosed with live head lice can return to class after appropriate treatment has begun. Nits may persist after treatment, but successful treatment should kill crawling lice. However, check with your school to determine its policy.

*Reapplication required in 7 to 10 days for complete elimination.

RID® lice products FAQs and information

Wetting the hair can dilute the treatment. It is critical that you are careful about reading directions before using the product.

Rinse the Shampoo from the hair. Continue with the combing procedure in Step 2. Apply another treatment on DRY hair 24 hours later. This will be the Day One application. Re-apply treatment 7 to 10 days later to kill any newly hatched lice. Continue with the combing procedure after each application to remove dead lice, eggs, and nits.

Because a second treatment with lice killing shampoo and combing must be done in 7 to 10 days to kill any newly hatched lice, it is important to make sure that you have enough RID® Lice Killing Shampoo.

Each RID® Lice Killing Shampoo carton has a purchase guideline table on its side panel that can assist you in determining how much product you may need, depending on hair length.

Click here for help in determining the right amount of product

RID® Lice Killing Shampoo is available in:
2 FL OZ (59 mL)
4 FL OZ (118 mL)
8 FL OZ (236 mL)

RID® Home Lice, Bed Bug & Dust Mite Spray is available in:
5 OZ (141.8 g)

RID® Lice Elimination Complete Kit contains:
4 FL OZ (118 mL) Shampoo
2 FL OZ (59 ml) Lice & Egg Comb-Out Spray
3 OZ (85.1 g) Home Lice, Bedbug & Dust Mite Spray
Patented RID® Lice Comb

All sizes of the Shampoo and the Complete Kit contain step-by-step illustrated instructions.

Yes, there is an expiration date on the product packaging.

Yes, vacate the room after treatment and ventilate before reoccupying.

When all directions have been followed for the 3-step lice elimination process, you should be free of lice after the day of your final application. To ensure that you are lice-free, it is critical that all steps be followed according to package directions. The full treatment requires 7 to 10 days.

The kit contains two sprays:

  1. Lice & Egg Comb-Out Spray: to be used on the head to aid in detangling hair to make lice and egg comb-out easier. It can be applied as often as desired during the comb-out process. Click here for detailed instructions on how to remove lice and eggs.
  2. Home Lice Spray: to be used to kill lice and eggs on unwashable items such as rugs, furniture or car interiors. This product should NOT be used on the head.

No, Lice & Egg Comb-Out Spray is not currently sold separately. If you need more, you may use a an alternative combing aid.

Successful treatment requires using RID® Lice Killing Shampoo on Day One and then 7 to 10 days later. You should not complete the second shampooing sooner than day 7. However, it is important to check the hair continually and remove any nits or eggs that may have been missed in the initial combing process.

If you have recently completed the RID® 3-step process and have lice again, please consult a doctor or pharmacist before using RID® again.

Most lice will die within, or shortly after, the ten-minute dosing. Lice are very sensitive to light and will move quickly when alive. If you observe lice crawling after treatment, they are probably affected and will die shortly. You should just comb them out of the hair.

Only items that have come into direct head-to-head contact with the infested person within 2 days prior to treatment need to be cleaned. Examples of some household items that should be cleaned are:

  • Home and auto upholstery
  • Bed linens
  • Towels
  • Stuffed animals, toys
  • Headphones
  • Hats
  • Coats, scarves, gloves
  • Play mats
  • Clothing
  • Combs and brushes

No. Although RID® helps ensure complete lice elimination when used properly, it is designed for use in humans and is not approved for use on pets or any other animals. If you think your pet may have lice, be sure to contact your vet immediately.

Please see Step 2 of the proper Lice Treatment Steps.

While it is not necessary to use your own shampoo or conditioner after treatment, doing so will not interfere with RID®'s efficacy.

No. RID® should not be used on an infant (under 2 years of age) without consulting a doctor.

Yes. You must treat pubic lice in a manner similar to that used for head lice. Please refer to the Pubic/Body Lice section for more information.

RID® text reminder program FAQs

When you are ready to begin treatment with RID®, you can sign up for convenient treatment reminders to help you remember when to start your second* treatment.

*Remember, RID® Lice Killing Shampoo is designed to be used on DAY ONE and then again 7 to 10 days later, but not before.

You can sign up for treatment reminders by texting RIDLICE to 877-67.

In order to support the elimination of lice, RID®, treatment reminders can help ensure that you don’t miss your second lice treatment. By providing convenient reminders of when that second* treatment will be due, you can stay on track with your lice treatment plan.

In addition to treatment reminders, RID®text support also provides you with useful treatment tips and links to helpful videos to help make the most of your lice elimination with RID®.

*A second treatment is necessary to kill any newly hatched lice. Click here to learn more about the lice lifecycle.

When you sign up for treatment reminders, you will receive text messages designed to help remind you when your second treatment is due. This can help keep you on track and ensure that you don’t miss your second* treatment.

Additional text messages include information about specific steps in the lice treatment process. You will also receive links to instructional videos to help support your lice elimination efforts. You will not receive any additional messages once the second treatment is complete.

*Remember, RID® Lice Killing Shampoo is designed to be used on DAY ONE and then again 7 to 10 days later, but not before.

To cancel or unsubscribe from treatment reminders at any time, reply RIDSTOP. You will then be unsubscribed from all text messages relating to RID.

Call 1-800-RID-LICE for assistance or additional questions.

When you sign up for treatment reminders, we will send you a link to an instructional video that can help you learn how to apply your first RID lice treatment.

Message and data rates may apply.

You will receive 5 reminder messages over the next 10 days, from the date entered as DAY ONE of your lice treatment plan.

You will be asked to confirm the start date of your lice treatment. By confirming whether your lice treatment started yesterday, today or will start tomorrow, the timing of the text message reminders will be adjusted automatically.

RID® product calculator tool FAQs

Using the RID® Product Calculator is easy and takes only a few simple steps.

Step 1. Select from a menu the number of individuals you will be treating for lice.

Hit CANCEL to start again or CONTINUE to go to the next step.

Step 2. Select the hair length of the first individual requiring treatment (person 1). Choose from short, medium or long hair. You will be asked to repeat this step for each individual who requires treatment.

Once you have made your first hair length selection (for person 1), the page will refresh and you will be asked to select the hair length for the next person requiring treatment (person 2, person 3, and so on).

If you need to change an answer, you should select the BACK button at the bottom of the page.

If you are satisfied with your selections, you should select the RESULTS button. This will calculate the amount of household members needing treatment and the length of hair for each individual.

Step 3. The RID® Product Calculator will then provide you with the total amount of product(s) that you will need to purchase in order to complete two treatments for each individual affected by lice.

No. The RID® Product Calculator tool was designed only to help you calculate the total amount of product(s) that you will need to purchase in order to completely eliminate lice.

Yes. While primarily designed to be used to calculate the total amount of product(s) you will need to purchase to completely eliminate lice, the RID® Product Calculator tool also provides you with a checklist of helpful lice elimination tips as well as a coupon to save money on your RID® product purchase. These additional functions are only available on the mobile version of the RID® Product Calculator.

The RID® Product Calculator determines the amount of RID® Lice Killing Shampoo that you will need to purchase for two complete treatments for each individual affected by lice.

If you are interested in purchasing the RID® Lice Elimination Complete Kit — a complete kit that includes RID® Lice Killing Shampoo,a RID® Lice Comb, RID® Lice & Egg Comb-out Spray, and RID® Home Spray—the RID® Product Calculator can also tell you how many kits you will need. Combing is an essential step to remove 100% of eggs.

Yes. You will be asked to enter the specific number of people in your household to be treated. The RID® Product Calculator will determine the total amount of RID® products that you will need to purchase.

If, at any point, you have incorrectly entered information, simply hit the BACK button to go to the previous page and re-enter your information correctly.

You can find a link to the RID® Product Calculator on the home page of this website.

While the RID® Lice Elimination Complete kit includes RID® Lice & Egg Comb-out Spray, the comb-out spray is not sold separately at this time. If you require additional product to assist with detangling during a comb-out session, a regular hair conditioner can be used..

Use the RID® Product Calculator tool to estimate how much product you may need to purchase for each person affected by lice.
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