What is the recommended treatment for scabies?

Scabies Treatment

Permethrin 5% cream applied from the neck down (including scalp in infants) for 8-14 hours is the first-line treatment for uncomplicated scabies, with one application generally being curative. 1, 2, 3

First-Line Treatment Options

Topical Permethrin (Preferred)

• Apply permethrin 5% cream to all areas of the body from the neck down and wash off after 8-14 hours 1, 2, 3
• For infants, young children, and geriatric patients, also treat the scalp, hairline, neck, temple, and forehead 1, 2, 3
• Approximately 30 grams is sufficient for an average adult 3
• One application is generally curative 3
• Permethrin is particularly recommended for pregnant women, lactating women, infants, and young children due to its safety profile 1, 2

Oral Ivermectin (Alternative First-Line)

• Dose: 200 μg/kg, repeated in 2 weeks 1, 2
• Must be taken with food to increase bioavailability and epidermal penetration 1
• Contraindicated in children weighing less than 15 kg due to neurotoxicity risk 2
• Avoid in pregnant and lactating women due to limited safety data 2
• No dosage adjustments needed for renal impairment 1

Special Populations

Pregnant and Lactating Women

• Use permethrin exclusively—avoid ivermectin 2

Infants and Young Children

• Permethrin is preferred; apply to scalp, temple, and forehead in addition to body 2, 3
• Do not use ivermectin in children <15 kg or infants <2 months old 2
• Avoid lindane, benzyl alcohol lotion, and malathion in infants <2 months 2

Crusted (Norwegian) Scabies

• Requires aggressive combination therapy due to massive mite burden (thousands to millions of mites) 1
• Regimen: 5% permethrin cream applied daily for 7 days, then twice weekly until cure, PLUS oral ivermectin 200 μg/kg on days 1,2,8,9, and 15 1, 2
• Single-application permethrin or single-dose ivermectin alone will fail 1
• This occurs in immunodeficient, debilitated, or malnourished persons and is far more contagious than typical scabies 1

Alternative Treatments (Less Preferred)

• Lindane 1%: Apply for 8 hours, but avoid in children <10 years, pregnant/lactating women, and persons with extensive dermatitis due to neurotoxicity risk 1, 2
• Sulfur 6% ointment: Apply for 3 consecutive nights 1
• Benzyl benzoate 25% lotion 4
• Malathion 0.5% aqueous lotion 4

Contact and Environmental Management

Contact Tracing and Treatment

• Examine and treat ALL persons with sexual, close personal, or household contact within the preceding month, even if asymptomatic 1, 2
• Failure to treat contacts simultaneously is the most common cause of treatment failure 1

Environmental Decontamination

• Machine wash and dry bedding, clothing, and towels using hot cycles, or dry clean 1, 2
• Alternatively, remove items from body contact for at least 72 hours (or 2 days minimum) 1, 2
• Fumigation of living areas is unnecessary 1, 2

Follow-Up and Persistent Symptoms

Expected Post-Treatment Course

• Rash and pruritus may persist for up to 2 weeks after successful treatment—this is NOT treatment failure 1, 2, 3
• Persistent pruritus after treatment is rarely a sign of treatment failure and is not an indication for retreatment 3

When to Retreat

• Consider retreatment only after 2 weeks if symptoms persist AND live mites are observed 1, 2, 3
• Demonstrable living mites after 14 days indicate that retreatment is necessary 3

Reasons for Treatment Failure

• Inadequate application of topical treatments (missing critical areas like under nails, scalp in infants) 1
• Failure to treat all close contacts simultaneously 1
• Reinfection from untreated contacts or fomites 1
• Not repeating ivermectin dose after 2 weeks 1

Critical Pitfalls to Avoid

• Never use lindane after bathing, as this increases absorption and neurotoxicity risk 1, 2
• Never skip the second dose of ivermectin at 2 weeks—essential for complete eradication 1
• Never use single-application permethrin for crusted scabies—it will fail 1
• Never use ivermectin alone for crusted scabies without topical therapy—insufficient given mite burden 1
• Never expect immediate symptom resolution—pruritus can persist 2 weeks post-treatment 1, 3