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High in vitro efficacy of Nyda L, a pediculicide containing dimeticone
F A S Oliveira1, R Speare, J Heukelbach
1Department of Community Health, School of Medicine, Federal University of Ceará, Fortaleza, Brazil.
Background:
The therapy of pediculosis remains a common problem in clinical practice. As resistance to commonly used chemical pediculicides is constantly increasing, there is a need for new effective compounds.
Study Design:
The efficacy of Nyda L, a new pediculicide containing a high concentration of dimeticone, was assessed in an in vitro trial and compared with three reference products (Hedrin containing 4% dimeticone, Lyclear containing 1% permethrin, and Prioderm containing 1% malathion) and a negative control group. Head lice were collected from heavily infested patients in a resource-poor community in Northeast Brazil, where no resistance against pediculicides has been reported thus far. In each of the five groups, 50 adult fully vital lice were tested. We used a dip test (immersing head lice in the undiluted products for 3 min, washing off products after 20 min). Using predefined criteria for mortality, the lice were monitored at different points in time, for a period of 24 h.
Results:
Nyda L and Prioderm killed all head lice already after 5 min. The efficacy of Nyda L was better than of Lyclear. Lice treated with Hedrin resurrected after several hours and did not show a significantly higher mortality compared with the control group after 24 h.
Conclusion:
Nyda L can be regarded as a very efficacious pediculicidal compound, killing all lice in vitro within 5 min.
