Lindane for treating head lice

February 19, 2009 | Leave a Comment

Lindane is the most toxic head lice killer (pediculicide) available.  It is a cyclodiene pesticide. Patients report an unpleasant sensation when using this treatment. This is caused by the head lice twitching on the scalp as they experience a slow death.

There is another disadvantage to using Lindane - it is not greatly successful in killing the head louse eggs (only 45 – 70% ovicidal) which means that re-infestation is likely and one treatment will definately NOT eradicate head lice.

There are claims that, because of its widespread and sustained use, head lice are also becoming resistant to Lindane. However, it is a toxic substance and sustained use carries a risk of side – effects.

To reduce the chances of side-effects, patients should use no more that 2oz of Lindane shampoo per treatment. Patients should also wear gloves to reduce absorption into the blood stream. If there is broken skin it should not be applied.

Lindane also increases the absorpancy of the hair meaning that no other hair products or oils should be applied for several days afterwards to prevent undesired effects on the hair.

 On balance, there are much safer options for treating head lice than using Lindane.  In many parts of the world it has been banned from animal usage…which should give us pause for thought before using it on humans.

Lindane is often a low-cost treatment for head lice and serious side-effects experienced have usually been experienced through misuse. However, if cost is an issue, a high quality nit comb and hair conditioner is a cheap and effective treatment for head lice.

Are Synergised pyrethrins effective treatment for head lice?

January 18, 2009 | Leave a Comment

What is synergised pyretherin?

Synergised pyretherin is the name given to a chemical insecticide that the Chrysanthemum plant produces naturally.

Are synergised pyrethrins effective for killing head lice?

Head lice have the ability to oxidise the chemicals in synergised pyrethrins quite easily unless a synergising agent is added to boost their pesiticidal effectiveness. The most common additive of this kind is Piperonyl butoxide (derived from petroleum). The FDA states that this chemical combination is both safe and effective (class 1) for use of hair and scalps.

How is this combination used to treat head lice?

The most common carrier for synergised pyrethrins is shampoo that is lathered on wet hair and left for 10 minutes to before rinsing and re-washing the hair with non-medicated shampoo. This treatment will kill live lice but is not completely effective in killing head louse eggs. For this reason, treatment needs to be repeated in 7 – 10 days time to kill off any newly hatched head louse eggs before the nymphs become old enought to breed. This is FDA’s advice even though some products claim to kill both lice and eggs and therefore suggests one treatment for effective head lice elimination.

Cautionary advice about using synergised pyrethrins….

•  If you are allergic to Chrysathemums, kerosene, ragweed or any product derived from petroleum, you must not use synergised pyrethrins to treat head lice.
• In any case avoid using the product near to mucous membranes and wash hands thoroughly after use.
• Some patients are claiming that lice are becoming resistant to synergised pyrethrins. Anecdotal evidence seem to back this up but scientific research is yet to be done on head lice resistance to treatment.
• The Federal Trade Commission website can also be visited to see evidence of patients sold synergised pyrethrins as a product effective in killing head lice in a single treatment who have discovered that this is misrepresentation. This can be distressing for people (already distressed by having head lice) thinking they have effectively dealt with the problem then finding they are still infested with head lice.