well i never ever use any treatment....i think they are all poisons!!!!
i don't mean that badly tho if anyone here does use them but my kiddies have immune deficiancys and very bad asthma so i don't like the thought of using them
for mine I use the 'nitty gritty' comb which gets the lice and the eggs....tis a fab comb and the only one which really does do what it says.
i wash hair every other day, and while the conditioner is in go thro the hair with the comb, rinsing the comb after each stroke in clean water to get rid of any lice/nits.
do this for about 2wks and you should be completely clear.
does require dedication for those two weeks, but it gets them, and you can do without the need for lotions, which you would still need to use with a net comb anyway, and nowadays you can't guarantee them working anyway!
as for washing bedding....no need to bother in my experience. lice can't last a day on bedding anyway, and it has never made any difference in my opinion. sharing beds tho.....now that is what makes them spread in my house..... and . all mine tend to bed hop....ownder why it is that I have four bedrooms in fact....most night at weekends I can go check on them all and find them all in one room, if not even all in one bed!!!!.
that they love each other that much tho...
HTH re the lice advice tho