If nits are yellow, tan, or brown, it means the lice haven't hatched yet. If the nits are white or clear, the lice have hatched and just the egg remains. Lice eggs hatch within 1 to 2 weeks after they're laid.
Eggs that still contain a louse embryo are brownish in color, while the empty egg shells are white to grey. As the hair grow approximately 1cm a month, eggs that are about 1cm from the scalp are more than likely to have already hatched or to contain a dead embryo.
Dead nits are often black in colour and are found well away from the scalp. Nits are laid on the hair shaft within 1cm of the scalp and take about 7-10 days to hatch into head lice.
Don't Obsess Over Nits
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.
Nits often appear yellow or white although live nits sometimes appear to be the same color as the hair of the infested person. Nits are often confused with dandruff, scabs, or hair spray droplets. Head lice nits usually take about 8–9 days to hatch.
But unfortunately, the nits will not simply fall out your hair. The lice themselves take 7 to 11 days to hatch, so after that what is attached to the hair is the empty eggshell or the dead nit. These will stay attached to the hair and as the hair grows you will find them further and further down the hair shaft.
It's possible that the nits are leftover from a previous infestation and are no longer viable, which means they are dead and won't hatch. It's difficult to tell the difference, so you should still treat any nits you find, even if there are no lice.
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.
Children can have a few nits without actually having a case of head lice. Usually children have no more than 10 to 20 live lice. Good lighting is important when you are checking. Head lice move fast and are hard to see.
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.
After Treating with Lice Medicine
Check for lice again in 8 to 12 hours. Use the nit comb to remove dead lice and nits. If some are still present but moving slowly, do not shampoo again. If lice are still active and no dead lice are found, call your health care provider.
Infestation timeline
So if you look on the scalp and see no visible adult lice and several small nits, it's likely that you've caught lice in the earlier stages and had them for less than 2 weeks. Nits and nymphs: 1.5 to 2 weeks. If you see nits and small, moving lice, you've likely had lice for 1.5 to 2 weeks.
If the nits are white or clear, the lice have hatched and just the egg remains. Lice eggs hatch within 1 to 2 weeks after they're laid. Besides seeing nits or lice on the head, itching — or the feeling of something moving around on the scalp — is another clue that you might have lice.
Nymphs mature into adults about 9–12 days after hatching. To live, the nymph must feed on blood. Adult: The adult body louse is about the size of a sesame seed, has 6 legs, and is tan to greyish-white.
Repeat treatment every day or every other day for 2 weeks. Some lice eggs (nits) survive head lice treatments. The only way to be sure that lice won't come back is to pick out all nits. Nits left on the hair can hatch and cause a new case of head lice.
Ivermectin (Sklice).
This lotion kills most head lice, even just-hatched lice, with just one use. You don't need to comb out lice eggs (nits). Children ages 6 months and older can use this product.
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.
Treating head lice. With the hair wet and full of conditioner, it is difficult to see whether any lice or nits have been removed. However, dry combing, which is easier to do, allows success of louse removal to be seen and has been successful in ten out of ten separate infestations.
Appearance. Head lice have six legs and are usually grayish-white or tan. However, they can camouflage, so they may appear darker or lighter to match different hair colors.
Do dead lice sink or float? They will sink. The nits, which are the eggs, will float to the top of the water, they are often brown and a tear drop shape.
Adult lice can't live longer than 24 hours or so on nonhuman surfaces like carpets, hardwood floors, clothing, furniture, sports helmets, headphones, or hair accessories. However, if you have identified lice in your home, isolate and wash those items and areas within at least 72 hours.
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.
You can find head lice on the scalp, neck, and ears.
By comparison, the researchers found that a normal hair dryer aimed at the base of hair, divided into 20 large sections, killed 55.3% of hatched lice and 97.9% of lice eggs after 30 minutes of blow drying.
The life cycle of the head louse has three stages: egg, nymph, and adult. . They are 0.8 mm by 0.3 mm, oval and usually yellow to white. Nits take about 1 week to hatch (range 6 to 9 days).