When choosing the best head lice shampoo, it is helpful to take into account three important factors. Considering the toxicity and safety of the chemicals in the shampoo, its ability to eliminate both live lice and eggs, and its reported effectiveness can all be helpful in determining which shampoo is best. There are many types of head lice shampoo, and the most effective varieties kill the head lice as well as the live eggs, or nits, the lice lay.
Head lice can cause itching, which can irritate the scalp and cause redness. Using a head lice shampoo that will not add to the irritation is important. Most head lice shampoos contain chemical pesticides to kill the live lice. These types require two separate applications. Most head lice treatments do not eliminate the eggs, or nits. Therefore, treating the existing lice and then applying the shampoo again later ensures that the eggs that hatched after the first use are also eliminated.
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Live head lice lay eggs in the hair, "gluing" them to the hair shaft very close to the scalp. These can include empty eggs, from which lice have hatched, or live eggs that have not yet hatched. It can be difficult to remove all of the eggs without a very finely toothed comb. Head lice shampoo packages that contain either a plastic or a metal comb to remove the nits can be a good choice.
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Pesticide-free head lice shampoos are available, as well. These types generally use natural oils such as lavender to aid in combing the live lice as well as the eggs out of the hair. Some of the chemicals included in head lice shampoo may not be safe for use on children under five years old. In cases where young children contract lice, the organic or natural head lice shampoos are a useful alternative. Chemical free shampoos are commonly sold at local grocery or drug stores.
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Prescription grade head lice shampoos and treatments are also available, though they are much stronger than over-the-counter varieties. Prescription types are usually reserved for infestations that are not responding to the traditional methods of lice removal. In many cases, head lice infestations can be eliminated using traditional head lice shampoos and treatments from a local drug store. Removing the nits after the shampoo has been used is one of the most important steps in eliminating lice infestation. This will prevent additional lice from hatching and laying more eggs.