An increasingly popular ‘alternative’ treatment involves the use of food-grade oils, hair gels and other products in attempts to smother lice on the scalp. Certain silicone-like oils (dimethicone or dimeticone) are formulated into products marketed to smother head lice. Many people have provided anecdotal reports of their successes with this method, but we have also heard of nearly an equal number of failures. As with any hair conditioner, oils may lubricate and ease efforts to pass louse or nit combs through the hair. Olive oil (or any similar food-grade product) would seem intrinsically safe, but may have associated hazards, nonetheless. Oil may cause accidents (slips), and would be difficult to remove from the hair and scalp (detergents can cause irritation). Do not use motor or machine oils, as these materials can be harmful. Lice will not be killed by swimming or by holding one’s scalp under fresh or salt water.
Egg (nit) of the head louse (Pediculus humanus capitis) on a hair. The picture was taken after an anti-lice treatment (Oxyphthirine - a substance based on Triglycerid producing a kind of film at the surface of the eggs and lice that induce asphyxia). This egg is therefore dead and its aspect can be slightly different from an alive egg. It seems to be slightly dehydrated.