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"Does cold temperature kill lice?"


My daughter just brought home a case of head lice from school, and I'd like to kill them in the most natural way possible. I thought maybe I could freeze them with one of those cold-sprays. Is this possible, or should I just by the whole shampoo and comb package?


The management of head louse (pediculus humanus capitis) involves the assistance of pediatricians, dermatologists, and others. The head louse is very common and in 1997 it was estimated that one in every four elementary school children were infested. Most lice infestations are without symptoms but itching may occur as a result of an allergic reaction to the saliva, which is injected during feeding.

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Secondary bacterial infections may occur. Topical insecticides are the treatment of choice for pediculus capitis. These agents are permethrin, malathion, lindane, and benzyl alcohol. Lindane has neurologic side effects and should only be considered if refractory. If you want to avoid topical agents, wet combing with a fine tooth comb to remove lice and their eggs may be sufficient. Hair should be wet with an added lubricant such as hair conditioner, olive oil, or vinegar. This should be done for 15-30 minutes three to four times weekly until lice are no longer seen. If this mechanical therapy and topical therapy fail, oral ivermectin can be considered. Hair shaving may help. There is a comb with an electric current to electrocute lice exists and has some anecdotal success. There is no data for cold-sprays. High volume heated blow dry to the scalp for 30 minutes has been reported but not well-studied. It is not possible to make a diagnosis or management plan without seeing the patient. Therefore it is the strong recommendation to speak with your pediatrician before proceeding.

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