What can be done for a head lice infestation?

Several possiblities: The simplest and most effective way to get rid of lice is to shave the head; it's 100% effective 100% of the time. If that's unacceptable, then there are a variety of prescription and over the counter products that will kill them (the otc products are often ineffective). What ever you use, you will need to carefully and repeatedly pick every single nit out of the hair, or they might come back.

Wet Combing: In addition to dr. Levey's answer, there is strong evidence for using a fine-toothed comb in wet hair to remove lice, especially if shaving is not a good option, eg in many school-aged girls. If you choose to use insecticides, check with your doctor as local resistance patterns often dictate which product is best to use.