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.
Nits may remain after lice have gone. They are empty eggshells and stick strongly to hair. They will eventually fall out. If you prefer, a fine-toothed 'nit comb' can remove them.
They are very small and will be a dark golden-brown colour if they are about to hatch or are white if the louse has already hatched and left the egg. If they are full then they will be plump and shiny. What does a dead lice egg look like? A dead lice egg will be white or grey.
Nits are often confused with other things found in the hair such as dandruff, hair spray droplets, and dirt particles. If no live nymphs or adult lice are seen, and the only nits found are more than ¼-inch from the scalp, the infestation is probably old and no longer active and does not need to be treated.
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.
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.
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.
Head lice eggs (nits) cannot hatch and usually die within a week if they do not remain under ideal conditions of heat and humidity similar to those found close to the human scalp.
Use heat. Wash any items used or worn by the person in hot water, and dry them on high heat. Lice and nits die when exposed to temperatures higher than 130 F for more than 5 minutes. Wash anything that touched the person's skin or scalp, including jackets, hats, scarves, pillowcases, sheets, and headbands.
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.
Live lice eggs are small brown or tan coloured dots on hair shafts close to the scalp. These can be incredibly difficult to spot. Broken egg shells, or nits, are easier to spot. It's common for parents to mistake nits for dandruff.
Do not use a conditioner. It can keep the lice medicine from working. Rinse well with warm water and towel dry. Do not use the towel again until it has been laundered.
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.
Rinse the comb in a sink or bowl of warm water, and wipe dry. Continue section by section until the entire head is done. Make sure hair stays wet with conditioner during combing. Metal or plastic nit combs are available at your local pharmacy.
Adults: The adult louse is about the size of a sesame seed, has 6 legs (each with claws), and is tan to grayish-white. In persons with dark hair, the adult louse will appear darker. Females are usually larger than males and can lay up to 8 nits per day.
Nits are the eggs of head lice. Brown-black nits are eggs that haven't hatched into lice yet. White nits are eggs that have already hatched.
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.
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.
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.
Spinosad (Natroba).
Spinosad is approved for adults and children age 6 months and older. It can be applied to dry hair and rinsed with warm water after 10 minutes. It kills lice and nits and usually doesn't need repeated treatment.
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.
Females are usually larger than males and can lay up to 8 nits per day. Adult lice can live up to 30 days on a person's head. To live, adult lice need to feed on blood several times daily.