lice Treatment has definitely become more of a challenge for weary mothers because the strain of head lice is much stronger today. Over the years head lice have become resistant to the chemically toxic lice shampoo's parents were given to use to get rid of lice. As a result today we are finding it harder and harder to get rid of lice completely. To get rid of lice completely is the only way to end a lice infestation cycle. The problem with most head lice shampoo's today is that even though they may have a high kill rate, they don't kill all the bugs! The remaining nits re-hatch and in a week you wonder why you still have head lice.