Headlice, also known by their scientific name of Pediculus humanus capititis, are small, wingless parasites that feed off the human scalp. They are most commonly found behind the neck at the base of the skull and behind the ears. Their eggs are known as nits, and are the most obvious identifying feature of an infestation. Although the nits can be mistaken for dandruff, on a closer look, the eggs are oval-shaped. They are also very tricky to remove from the individual hair they are attached to.

After about a week or so, the nits hatch into baby lice, known as nymphs. These are identical to adults in appearance, but smaller in size. After another week, these nymphs are considered to be adults. Adult lice live for 30 days, feeding on human blood. Each louse has six legs, and attach to the hair with a hook-like claw at the end of each leg. This allows for a strong attachment to the hair, and because of this, headlice can be tricky to treat.

Infestations of headlice announce themselves with intense itchy sensations along the scalp, especially at the base of the skull. The flesh may feel like it is crawling around one's head. Sore red, sometimes bleeding spots can be seen resulting either from the lice or from scratching. Infestation may not be detected from the presence of adult lice- which are fast and hard to catch- but from their nits and from the symptoms described earlier.

It is important to know that an infestation of headlice does not mean that the person has poor hygiene. Normal shampoos and soaps, or laundry detergents alone are not enough to deter these annoying parasites. Lice can be very hard to get rid of and it is always hard to remove the nits from the hair strands. There are special combs and lice shampoo that is medicated and these can be used. There is also prescription medication that can be prescribed by a doctor to treat a lice infestation.

Several different medications exist to kill head lice. Pyrethrins and permethrin are the active ingredients in over-the-counter shampoos used to combat moderate cases of head lice. More serious cases may warrant the use of malathion or lindane. These chemicals are only available with a doctor's prescription. In all cases, anyone with regular close contact with the infected person should also be treated. All bedding and clothes worn by infected people should be promptly washed to eliminate lice and eggs. Once treatment has run its course, the previously infected person should use a fine-toothed, nit-picking comb to remove the dead lice and nits from the scalp.

There are many home remedies for head lice, such as soaking one's head in various liquids (examples include mouthwash containing alcohol, vinegar, shampoo, and mayonnaise). All of these remedies have the common trait of claiming to smother the scalp and kill lice and nits by suffocation.

Headlice, Pediculus humanis capitis, are parasites that live on the human scalp. A lice infestation is announced by intense itching and a crawling feeling on the scalp. The idea of lice is associated with dirtiness, but even very clean people can catch them. Regular soap is ineffective in removing them, but specialized lice treatment exists: medicated shampoos and precriptions like lindane or malathion. The entire household must be treated for lice. A finetoothed comb exists to pick the dead nits and lice out of the hairs. Home remedies for head lice include soaking the hair in lice-killing substances, tea tree oil, or mayonnaise.