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).
A nymph hatches from the egg and goes through several stages of growth before turning into an adult head louse. Nymphs look similar to adult head lice but are smaller, roughly the same size as a pinhead. Adult head lice are about 2–3 millimeters (mm) in length, which is roughly the size of a sesame seed.
You may be able to see the lice, but they're often hard to spot because they're small, avoid light and move quickly. Lice eggs (nits) on hair shafts. Nits stick to hair shafts and may be hard to see because they're very tiny. They're easiest to spot around the ears and the hairline of the neck.
Once the lice have spread to the person's head, the female louse will start to lay their nits or eggs; an infestation has begun. The first nymphs, or baby lice, will appear 7-10 days later. Nymphs will continue to eat and grow over the next 7-10 days.
Itching on the areas where head lice are present is the most common symptom. However, it may take up to 4 to 6 weeks after lice get on the scalp before the scalp becomes sensitive to the lice saliva and begins to itch. Most of the itching happens behind the ears or at the back of the neck.
Benzyl alcohol lotion, 5% has been approved by the FDA for the treatment of head lice and is considered safe and effective when used as directed. It kills lice but it is not ovicidal. A second treatment is needed 7 days after the first treatment to kill any newly hatched lice before they can produce new eggs.
Washing, soaking, or drying items at a temperature greater than 130°F can kill both head lice and nits. Dry cleaning also kills head lice and nits. Only items that have been in contact with the head of the infested person in the 48 hours before treatment should be considered for cleaning.
Coconut, tea tree oil, lavender, eucalyptus, rosemary, lemon grass, and peppermint are scents popularly believed to repel lice. Using any coconut scented shampoo and conditioner is an easy way to increase your defense.
Prevention of Head Lice
Weekly head checks and the use of mint spray is your best defense. Mint Spray Recipe: Put 10 drops of mint essential oil into 16 ounces of tap or bottled water in a spray bottle. Spray on hair at least daily.
Petroleum jelly (Vaseline).
Like olive oil, many moms swear by this (other options: styling gel or mayonnaise). The thick jelly supposedly suffocates lice by clogging their breathing holes. For best results, coat the hair and scalp, cover it overnight with a shower cap, and wash out the next morning. Comb for nits.
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.
Head-to-head contact with an already infested person is the most common way to get head lice. Head-to-head contact is common during play at school, at home, and elsewhere (sports activities, playground, slumber parties, camp). Although uncommon, head lice can be spread by sharing clothing or belongings.
Continue to check hair and use the nit comb to remove nits and lice every 2 to 3 days for 2 to 3 weeks. This process should be done for as long as nits and lice are still found on the head. Many lice medicines recommend a second treatment in 9 to 10 days.
Head lice are most active at night. Itching is the first and most common symptom but may not appear for weeks after contracting lice. The itching is caused by an allergic reaction to the bug bites which can cause sores or raw skin on the scalp.
Head lice are most active at night. They can cause such intense itching that your child could lose sleep over it. It's uncomfortable, but lice won't make you sick. They don't spread disease and they're not a sign that you're dirty.
Coconut, tea tree oil, lavender, eucalyptus, rosemary, lemon grass, and peppermint are scents popularly believed to repel lice. Using any coconut scented shampoo and conditioner is an easy way to increase your defense. At 1% concentration, tea tree oil killed 100% of head lice after 30 minutes.
Not everyone feels lice moving around on their scalp, but some people do. Dr. Garcia says that most of her patients say they “don't feel anything,” but others may get a creepy, tickling sensation as lice move around their head.
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.
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.
It is not usually possible to get rid of lice in one day, as an infestation needs to be treated. However, there are treatments that can help get rid of lice and symptoms caused by lice more quickly. Lice infestations must first be treated by improving the hygiene of the infected person.
First off, here's what not to do: don't shave your or your child's head, or coat it with petroleum jelly or mayonnaise or anything else designed to "suffocate" the parasite. You'll probably end up with greasy, smelly, lice-infested hair.