PYRETHRINS 0.33% AND PIPERONYL BUTOXIDE 3%
Place in Therapy
Place in Therapy
Pyrethrins 0.33% with piperonyl butoxide 3% is considered a second line option and alternative to Permethrin 1% in the treatment of lice.1 Although multiple studies such as Carson et al (1988) and Bainbridge et al (1998) have demonstrated the effectiveness of Pyrethrins in the treatment of lice, Pyrethrins has reduced efficacy in comparison to Permethrin.2,3 Carson et al (1988) found that both agents were effective and well tolerated; however, Pyrethrins was less efficacious than Permethrin for eradicating adult and nymphal lice on day 7 after treatment (93.5% patients were lice free in pyrethrins group as compared to 100% in permethrin group).2 According to Miller (2010), Pyrethrins is 45% efficacious after first application and 94% after second application.1 Pyrethrins has a killing time of 10-20 minutes. Due to its low ovicidal activity and lack of residual effect in removing nits, re-treatment is necessary 7-10 days after treatment.1 It is important as suggested by Miller (2010) that one should also consider the local resistance patterns when choosing a medication for lice, although Pyrethrins has demonstrated low incidence of resistance in Canada as compared to other countries.1
Pyrethrins 0.33% with piperonyl butoxide 3% is a well tolerated product. Its side effects are rare and mild, and they may include contact dermatitis, pruritis, burning, and stinging with repeat use. There are no known drug interactions with Pyrethrins. The product should not be used in children less than 2 years old, or people with known allergy to ragweed or chrysanthemums. Pyrethrins can safely be used in pregnant (Pregnancy Risk Factor C) and lactating women.4 With regards to cost, the price is comparable to other agents used in the treatment of lice, such as Permethrin and Lindane. Pyrethrins ranges from $10-20 depending on the volume of shampoo/conditioner ($10 for 50 mL, $25 for 200 mL), and patients are recommended to apply two treatments, with the second treatment applied 7-10 days after the first.5 It is recommended that for patients with long or thick hair, two bottles might be necessary per treatment, as hair need to be thoroughly soaked for the treatment to be effective.
References:
1. Miller, PF. Chapter 71: Parasitic Skin Infections: Lice and Scabies. In: Patient Self Care Helping Your Patients Make Therapeutic Choices 2nd ed. 2010; 679-690.
2. Carson ST, Tribble PW, Weart CW. Pyrethrins Combined with piperonyl butoxide (RID) vs. 1% Permethrin (NIX) in the treatment of head lice. AJDC. 1988; 142:768-769.
3. Bainbridge CV, Klein GL, Neibart SI, et al. Comparative study of the Clinical Effectiveness of a Pyrethrin-Based Pediculicide with Combing Versus a Permethrin-Based Pediculicide with Combing. Clin Pediatr. 1998; 37:17-22.
4. Lexi-Comp. Pyrethrin and Piperonyl butoxide. Available at: http://online.lexi.com.proxy.lib.uwaterloo.ca/lco/action/home/switch. Accessed March 8, 2013.
5.RxFiles. Head Lice. Available at: http://www.rxfiles.ca/rxfiles/modules/druginfoindex/druginfo.aspx. Accessed March 8, 2013.
Pyrethrins 0.33% with piperonyl butoxide 3% is considered a second line option and alternative to Permethrin 1% in the treatment of lice.1 Although multiple studies such as Carson et al (1988) and Bainbridge et al (1998) have demonstrated the effectiveness of Pyrethrins in the treatment of lice, Pyrethrins has reduced efficacy in comparison to Permethrin.2,3 Carson et al (1988) found that both agents were effective and well tolerated; however, Pyrethrins was less efficacious than Permethrin for eradicating adult and nymphal lice on day 7 after treatment (93.5% patients were lice free in pyrethrins group as compared to 100% in permethrin group).2 According to Miller (2010), Pyrethrins is 45% efficacious after first application and 94% after second application.1 Pyrethrins has a killing time of 10-20 minutes. Due to its low ovicidal activity and lack of residual effect in removing nits, re-treatment is necessary 7-10 days after treatment.1 It is important as suggested by Miller (2010) that one should also consider the local resistance patterns when choosing a medication for lice, although Pyrethrins has demonstrated low incidence of resistance in Canada as compared to other countries.1
Pyrethrins 0.33% with piperonyl butoxide 3% is a well tolerated product. Its side effects are rare and mild, and they may include contact dermatitis, pruritis, burning, and stinging with repeat use. There are no known drug interactions with Pyrethrins. The product should not be used in children less than 2 years old, or people with known allergy to ragweed or chrysanthemums. Pyrethrins can safely be used in pregnant (Pregnancy Risk Factor C) and lactating women.4 With regards to cost, the price is comparable to other agents used in the treatment of lice, such as Permethrin and Lindane. Pyrethrins ranges from $10-20 depending on the volume of shampoo/conditioner ($10 for 50 mL, $25 for 200 mL), and patients are recommended to apply two treatments, with the second treatment applied 7-10 days after the first.5 It is recommended that for patients with long or thick hair, two bottles might be necessary per treatment, as hair need to be thoroughly soaked for the treatment to be effective.
References:
1. Miller, PF. Chapter 71: Parasitic Skin Infections: Lice and Scabies. In: Patient Self Care Helping Your Patients Make Therapeutic Choices 2nd ed. 2010; 679-690.
2. Carson ST, Tribble PW, Weart CW. Pyrethrins Combined with piperonyl butoxide (RID) vs. 1% Permethrin (NIX) in the treatment of head lice. AJDC. 1988; 142:768-769.
3. Bainbridge CV, Klein GL, Neibart SI, et al. Comparative study of the Clinical Effectiveness of a Pyrethrin-Based Pediculicide with Combing Versus a Permethrin-Based Pediculicide with Combing. Clin Pediatr. 1998; 37:17-22.
4. Lexi-Comp. Pyrethrin and Piperonyl butoxide. Available at: http://online.lexi.com.proxy.lib.uwaterloo.ca/lco/action/home/switch. Accessed March 8, 2013.
5.RxFiles. Head Lice. Available at: http://www.rxfiles.ca/rxfiles/modules/druginfoindex/druginfo.aspx. Accessed March 8, 2013.