What do I need to know about Lice?

This post was prompted first by my wife, who works as a school nurse, and told me about seeing a boy who had to be treated for both lice and scabies at the same time, and next by a patient I saw, primarily for allergies, but then his mother asked me to look carefully at his hair.  There was a high suspicion of lice in my mind. 

 (Photo 1) More good photos are online.  We discussed the treatments: over-the-counter meds and prescription meds.  A good summary can be found at the CDC's website (although this site was last updated 11/2/10).  His mom asked me about using mayonnaise, which I never heard of.  The idea here is to suffocate the lice.  Some research led me to the Minnesota Department of Health's website.  I want to stress that any medication or home remedy must not be left on the person's scalp, because of the risk of irritating the skin, or causing a chemical burn.  The third and final thing that prompted me to write this post an announcement of a new prescription medication for lice: ivermectin.  You have to login to MEdscape to read the article, so if you can't then here's a pretty good summary on an open website.

Now for 2 obvious trivia questions: can anyone guess the origin of the phrases "to nit pick" and "to use a fine tooth comb"?

If you have questions about lice, ask your doctor....