Summarize:

Even if you do an overnight treatment, you must comb your (or the person with lice's) hair every night for three weeks to ensure there are no new lice. Use a specially designed lice comb. It should have metal teeth that are long and closely spaced to one another. Avoid using plastic combs or the free combs that come with lice shampoos. No head lice product currently available will kill all lice eggs. Treatments will kill lice that already have hatched, but eggs hatch at different times so new lice can be born after treatment. Within seven to 10 days, repeat your homemade treatment. Follow the same steps you used previously. This will help kill any newborn baby and adult lice. Using your comb, separate the hair into smaller pieces. Check each section for eggs. Look also for live or deceased insects. If you continue to find lice after your second treatment, consider trying a different alternative treatment or using a prescription from your doctor. Do not let lice go untreated in any case. While you should see the doctor immediately upon discovering lice, you might need a follow-up appointment. If you or your child’s lice does not improve within three weeks, visit your doctor. Also, if your child is itching her head and the skin breaks, she could get an infection. If you suspect this, seek medical treatment. There are many topical drugs available to treat head lice. Some are available over-the-counter (OTC) while others require a prescription. Lice may be resistant to some of these treatments, so you may have to try a different one if one is not effective. Make sure you speak with your doctor before using any of these treatments.  Permethrin 1% cream (OTC ) Malathion 0.5% lotion (Prescription only) Pyrethrin 0.33% shampoo (OTC) Benzyl alcohol 5% lotion (Prescription only) Spinosad 0.9% (Prescription only) Ivermectin 0.5% topical lotion (Prescription only) Lice cannot survive for long if they fall off a human because they cannot feed. In fact, they die within one to two days if they do not access human blood. Nevertheless, it is still good to clean your home and belongings to prevent reinfestation. Complete the following steps:  Machine wash all bed sheets and the affected person's clothing worn presently or two days prior to treatment. Set your machine to a hot water (130°F or 54.4°C) setting. Machine dry on high heat all washed items. Bring any dry-clean only clothing items to the cleaner. Place hairbrushes and combs in 130°F (54.4°C) water for five to 10 minutes. Vacuum all floors and furniture pieces. Particularly focus on areas where the affected person spent time. Avoid using fumigant sprays. These can be dangerous to humans.
Comb your hair. Repeat treatment one week later. Inspect hair. See a doctor. Clean your home and belongings.