Joyce
Have you tried Tee Tree oil shampoo? It works beautifully on irradicating head lice. In your case I would suggest adding some of the actual tee tree oil to the shampoo as well. My granddaughter was having the same problem with headlice until my daughter started using this shampoo. There have been no more reoccurances of the lice. It would not hurt to use this shampoo as a deterrant once a week. You can find more information on the net about tee tree oil shampoo.