Benzyl Alcohol Lotion (BAL) has been found effective against head lice in children. A study published in Pediatric Dermatology says the treatment, non-neurotoxic, had a success rate of 91.2 per cent after one week.
BAL 5% (known as Ulesfia
TM) works by suffocating lice, a method which has been attempted by treating with household items such as mayonnaise, olive oil and petroleum jelly. Studies have shown that overnight treatments with these home remedies may initially appear to kill lice, but later a "resurrection effect" occurs after rinsing, because lice can resist asphyxiation. This is accomplished by the louse's ability to presumably close its spiracles, the external entry points to the breathing apparatus, when submerged. Unlike commonly used asphyxiant remedies, scanning electron microscopy appears to indicate that benzyl alcohol lotion effectively asphyxiates lice by "stunning" the spiracles open, allowing the lotion, comprised of mineral oil and other inactive ingredients, to infiltrate the "honeycomb" respiratory apparatus and kill lice.
The phase III trials were comprised of two multicenter, randomized, double-blind, placebo-controlled trials, conducted among ten geographically diverse sites which assessed the clinical effectiveness and safety of benzyl alcohol lotion. 250 participants took part in the trials and were randomised to treatment or vehicle (lotion but with no active ingredient) groups, treatment was given at day one and day seven, and participants were checked for success at day eight and day 14. On day eight the treatment group had a success rate of 91.2% as an average of both trials, and a 75.6% success rate on day 14; in the vehicle group the success rates were 27.9% and 15.5% respectively.