‘Loss of efficacy of topical 5% permethrin for treating scabies: an Austrian single-center study’

Is Scabies becoming less sensitive to permethrin therapy?

“…According to the recent European guidelines, 2 one or two applications of 5% permethrin should be enough to eradicate the mite, so also the 10 patients who responded only after a median of 15 NOA have to be considered as non-responders to standard therapy. All these data led us to agree with recently published German and Austrian single-centre studies, 8,9 which hypothesized that a mite population with reduced susceptibility to permethrin is probably emerging around the world.…”

Comparison of Permethrin-Based Treatment Strategies against Scabies in Infants and Young Children

“…J o u r n a l P r e -p r o o f 13 a beneficial impact of repeated permethrin applications could not be demonstrated in young adults. 26 In contrast, in the current study cohort of infants and young children, concerned parents who might adhere more strictly to treatment instructions may partially account for the better outcome. No major issues regarding lack of compliance of the parents were documented, despite the more intense care required, especially for the intensified regimen.…”

“…The issue of mite resistance and/or tolerance to certain scabicides is controversial. 5,16,[25][26][27][28][29] Surprisingly, the majority of our subjects, who had received previous permethrin-containing therapies without success, showed clearance of infestations with one of the three permethrinbased regimens utilized in the study. This suggests that mite resistance to permethrin may be less likely and/or that the causes for therapy failure may relate to insufficient adherence to J o u r n a l P r e -p r o o f 12 treatment, inadequate implementation of hygienic measures, or deficiencies in the treatment procedures.…”

Use of oral ivermectin in permethrin‐resistant scabies: A pilot study

“…1 However, in Italy permethrin is almost the exclusive treatment used, since OI has only very recently become available on the national market.As previously reported by our group and others, scabies is clearly becoming less sensitive to permethrin therapy. [2][3][4][5] As a consequence, we treated a series of patients who failed topical treatments with OI, achieving an optimal outcome. 2 Following this observation, we started an explorative observational study on the use of OI in non-responder patients to permethrin.From March 31, 2021 to February 10, 2022, we registered all the confirmed scabies (as defined by the Consensus Criteria 6 ) evaluated at the sexually transmitted infections clinic of Trento, Italy, who were treated with OI, after the failure of a single cycle of permethrin.Although the topical treatment protocol we adopt is more aggressive than that suggested by the European Guidelines, 1,2 we follow exactly the dosage indicated for OI: 200 μg/kg as two doses 1 week apart.…”

“…As previously reported by our group and others, scabies is clearly becoming less sensitive to permethrin therapy. [2][3][4][5] As a consequence, we treated a series of patients who failed topical treatments with OI, achieving an optimal outcome. 2 Following this observation, we started an explorative observational study on the use of OI in non-responder patients to permethrin.…”