Generally, if no live crawling insects are seen three weeks after the treatment, it's safe to assume that they are gone. Nits would have hatched by that time if they were alive. Nits and their shells may remain in the hair for some time but won't be viable.
After each treatment, checking the hair and combing with a nit comb to remove nits and lice every 2–3 days may decrease the chance of self–reinfestation. Continue to check for 2–3 weeks to be sure all lice and nits are gone.
With effective treatment, head lice will completely go away after two to three weeks. The duration is dependent on how many lice made a home in your hair. Make sure you follow the instructions on your medicated shampoo, lotion or cream to get rid of lice quickly.
Most treated nits (lice eggs) are dead after the first treatment with Nix. The others will be killed with the 2nd treatment. Removing the dead nits is not essential or urgent. However, it prevents others from thinking your child still has untreated lice.
After treatment, your skin may still itch for a week or more. This is because of your body's reaction to the lice. Follow-up care is a key part of your treatment and safety.
If you do not comb out all the remaining nits, they will hatch and restart the cycle in 7-10 days from that point. That's why we recommend 3 treatments over a 12-day period of time. This stops the life cycle of lice. These are nits at different stages and a louse.
Head lice should die within a day. Some lotions and sprays come with a comb to remove dead lice and eggs. Some treatments need to be repeated after a week to kill any newly hatched lice.
About a week and a half after hatching, the louse grows to the size of a sesame seed, with six clawed legs and a tan to grayish-white color. The CDC says lice may look darker on people with dark hair. Like a nymph, an adult louse survives on regular human blood meals.
Can someone have nits but no lice? It may be possible to have nits but no lice. If a person cannot find any nymphs or adult lice in the scalp and the nits are more than a quarter of an inch from the scalp, these may be dead and from an old infestation.
Adult head lice can survive for 2 days and nits for around 1 week on a hairbrush. Soaking combs or hairbrushes in hot water of at least 130°F (54.4°C) for 5–10 minutes will kill any lice and nits.
You do not need to use regular shampoo or conditioner after the lice treatment. In fact, it is best to not shampoo again for 2 days, in order to give the medicine time to work. The medicine will kill the live lice bugs, generally within 12 hours.
After the first treatment, when the egg-laying lice are eliminated, you are no longer contagious.
One method that people have attempted to use is a blow dryer or hair straightener, thinking the heat would dry up and kill any lice. This idea is heading in the right direction, and while desiccation can be used to kill lice, it's important to note that a regular hair dryer or straightener will not treat lice.
The head lice may have become resistant to the treatment. If the treatment used does not kill the head lice, your health care provider and pharmacist can help you be sure the treatment was used correctly and may recommend a completely different product if they think the head lice are resistant to the first treatment.
DO NOT over treat. Some louse shampoos can be neurotoxic and overuse can damage the nervous system. Wear gloves when treating more than one person with head louse shampoo. If more than two treatments are required to control an infestation, talk to the School Nurse(s) or the Health Department about alternative methods.
How many head lice are usually found on an infested person? Typically, 10–15 head lice are found. The number of lice often depends on personal hygiene, for example, how often the person bathes, shampoos, or changes and washes his/her clothing.
Avoid head-to-head (hair-to-hair) contact during play and other activities at home, school, and elsewhere (sports activities, playground, slumber parties, camp). Do not share clothing such as hats, scarves, coats, sports uniforms, hair ribbons, or barrettes. Do not share combs, brushes, or towels.
New eggs are attached to the hair shaft very close to the scalp. Eggs that still contain a louse embryo are brownish in color, while the empty egg shells are white to grey.
Seven to nine days after the first treatment
No approved treatment for head lice can kill all the eggs during the first treatment. After applying the second treatment, comb through the hair with the lice comb. Wait two days to wash the hair. Continue to comb through the hair with the lice comb once a day.
Avoid sleeping in the same bed as the person with an active lice infestation. Avoid sitting where the person with lice has sat in the past two days. Wash linens and clothing in hot water and dry on high heat. Place stuffed animals, pillows and items that cannot be washed into an airtight bag for two weeks.
Spare yourself. But you should vacuum any cloth furniture that your child's head may have touched in the two days before you realized she had lice. 5. You don't need to throw out your brushes and combs.
A preventative shampoo and spray can break the life cycle. A shampoo that kills lice before they can lay eggs is critical for closing the “bridge” from one head to another.