Pyrethrins combined with piperonyl butoxide (RID) vs 1% permethrin (NIX) in the treatment of head lice
D. S. Carson, P. W. Tribble and C. W. Weart
Department of Community Pharmacy Practice and Administration, Medical University of South Carolina, Charleston 29425.
In a randomized controlled trial, 58 subjects were treated for Pediculus
humanus var capitis with either pyrethrins combined with piperonyl butoxide
(RID, Pfizer Inc, New York) or 1% permethrin (NIX, Burroughs Wellcome Co,
Research Triangle Park, NC); 31 subjects received RID and 27 subjects
received NIX. Both products were applied according to manufacturer's
directions so that NIX was applied only on the first visit and RID was
applied on the first visit and again seven days later. After each treatment
with a pediculicide, the comb supplied by the manufacturer was used to
remove nits. Seven days after the initial visit, NIX was determined to be
significantly better than RID for eradicating the lice infestation. Of the
27 subjects receiving NIX, 26 were live free vs 14 of the 31 RID-treated
subjects. At day 14, there was no statistically significant difference in
the treatments (27 of 27 NIX-treated vs 29 of 31 RID-treated subjects were
lice free). The RID comb was superior to the NIX comb for nit removal. Both
treatments were effective and well tolerated, and no subject experienced
adverse reactions.
