Scabies and Pediculosis Treatment Guidelines

Introduction

• Scabies and pediculosis are parasitic infections that require prompt treatment to prevent complications and transmission, with guidelines supported by the Centers for Disease Control and Prevention (CDC) and the American Academy of Pediatrics (AAP) 1, 2, 3, 4, 5

First-Line Treatment

• The CDC recommends permethrin 5% cream as the first-line treatment for scabies, applied from the neck down, with a treatment duration of 8-14 hours, and a cure rate of 89-95% at 4 weeks after treatment 2, 5, 3
• Permethrin 1% cream rinse is recommended for pediculosis pubis, applied to affected areas for 10 minutes 3
• For head lice, the AAP recommends 1% permethrin lotion applied to damp hair for 10 minutes, with a cure rate of 89-95% at 4 weeks after treatment 4

Alternative Treatments

• Ivermectin is an alternative effective treatment for scabies, especially when other treatments have failed or are not tolerated, with an oral dose of 200 μg/kg repeated after 14 days or as a topical formulation at 0.8% 2, 1
• Sulfur 6% ointment is a treatment option, applied nightly for 3 nights and washed off 24 hours after last application 5
• Lindane 1% lotion or cream is a treatment option, but should be avoided due to its association with neural tube defects and potential neurotoxicity, especially in children under 10 years and in pregnant or lactating women 2, 5

Decontamination and Prevention

• Decontaminating bedding and clothing by machine washing and drying using hot cycle, dry cleaning, or removing from body contact for at least 72 hours is recommended to prevent re-infestation 3, 5
• Treating all household members and close contacts simultaneously, even if asymptomatic, is recommended to prevent reinfection 2, 3, 5
• The following strategies can be used for decontamination:

Special Populations

• Permethrin is a safe and preferred treatment for pregnant/lactating women, with low mammalian toxicity and minimal allergic side effects 3, 2, 5
• Ivermectin is generally considered compatible with breastfeeding, as low concentration excretion in breast milk means amounts ingested by the infant are likely to be small 1
• Caution is advised in patients with reduced hepatic function when using ivermectin, as the safety of the drug in this population is not well established 1
• Azithromycin can significantly increase serum ivermectin concentration, which may increase the risk of hepatotoxicity, particularly in patients with pre-existing liver disease 1

Follow-Up and Retreatment

• Patients should be evaluated after 1 week to assess treatment response, and retreatment is indicated if live mites are still present after 14 days 3
• Pruritus may persist for several weeks after successful treatment of scabies and is not an indication for retreatment 3
• Follow-up examinations should be performed to verify eradication of infection 2, 1
• Before treating with ivermectin, Loa loa infection must be excluded in people who have traveled to endemic regions to prevent severe adverse reactions 2