What is the recommended treatment for scabies?

Treatment for Scabies

Permethrin 5% cream is the first-line treatment for uncomplicated scabies, applied to all areas of the body from the neck down and washed off after 8-14 hours. 1, 2, 3

First-Line Treatment Options

Topical Permethrin (Preferred)

• Apply permethrin 5% cream from the neck down to the entire body surface, including under fingernails and all skin folds, leave on for 8-14 hours, then wash off. 1, 2, 3
• One application is generally curative in most cases. 2, 3
• For enhanced efficacy, consider applying the cream once daily for two consecutive days rather than a single application—this regimen showed 87.2% cure rate versus 61.8% with single application. 4
• In infants and young children, include the scalp and face in the application area. 2, 5
• Permethrin is the preferred agent for pregnant women, lactating women, and children as young as 2 months of age due to its safety profile. 1, 3, 6

Oral Ivermectin (Alternative First-Line)

• Oral ivermectin 200 μg/kg as a single dose, repeated in 2 weeks, is an effective alternative to topical therapy. 1, 2, 3
• Take with food to increase bioavailability and epidermal penetration. 1
• Do not use in children weighing less than 15 kg due to potential neurotoxicity. 3
• Particularly useful for institutional outbreaks, patients who cannot apply topical therapy properly, and mass treatment campaigns. 7, 5

Alternative Treatments (When First-Line Options Unavailable)

• Lindane 1% should be avoided due to neurotoxicity risk, especially in children <10 years, pregnant/lactating women, and persons with extensive dermatitis. 1, 2, 3
• If lindane must be used: apply thinly from neck down, wash off after 8 hours, never apply after bathing (increases absorption and toxicity). 8, 2
• Benzyl benzoate 25% lotion is an alternative in some regions. 7
• Sulfur 6% ointment applied nightly for 3 nights is another option, though less convenient. 8, 1

Special Populations and Situations

Crusted (Norwegian) Scabies

Requires combination therapy due to extremely high mite burden: 1, 2, 3

• Topical permethrin 5% 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
• This population has high infectivity and requires aggressive treatment. 2

Pregnant and Lactating Women

• Permethrin is the preferred treatment due to limited systemic absorption and established safety profile. 1, 3, 6
• Avoid ivermectin due to insufficient safety data in pregnancy. 3

Infants and Young Children

• Permethrin is safe and effective in children as young as 2 months. 3, 6
• Must include scalp and face in treatment application. 2, 5
• Avoid ivermectin in children weighing <15 kg. 3

Contact and Environmental Management

Contact Tracing and Treatment

• All persons with close personal, sexual, or household contact within the preceding month must be examined and treated simultaneously, even if asymptomatic. 1, 2, 3
• Failure to treat all contacts simultaneously is the most common cause of treatment failure. 2
• The look-back period is 2 months for partner management. 7

Environmental Decontamination

• Machine wash and dry bedding and clothing using hot cycle, or dry-clean, or remove from body contact for at least 72 hours. 8, 1, 2
• Mites survive on clothing for up to 4 days without skin contact but only 1-2 days at room temperature. 2
• Place non-launderable items in a dryer for 10 minutes on high setting, or isolate for minimum 2 days (or 3 weeks for rigorous approach). 5
• Fumigation of living areas is unnecessary. 8, 1

Follow-Up and Management of Persistent Symptoms

Expected Post-Treatment Course

• Rash and pruritus may persist for up to 2 weeks after successful treatment—this is NOT treatment failure and does NOT require immediate retreatment. 1, 2, 3
• Approximately 75% of patients with pruritus at 2 weeks will have resolution by 4 weeks. 6
• Persistent symptoms are due to hypersensitivity reaction to dead mites and their debris, not ongoing infestation. 2

Indications for Retreatment

Retreatment is indicated only if: 1, 2, 3

• Symptoms persist beyond 2 weeks AND
• Live mites are demonstrated on examination after 14 days

Reasons for True Treatment Failure

• Inadequate application of topical treatment (missing skin folds, under nails, face/scalp in children). 2
• Failure to treat all close contacts simultaneously. 2
• Reinfection from untreated contacts or contaminated fomites. 1
• Not repeating ivermectin dose at 2 weeks. 1, 2
• Using lindane after bathing (increases toxicity without improving efficacy). 2

Critical Pitfalls to Avoid

• Not treating all close contacts at the same time—the leading cause of treatment failure. 2
• Inadequate topical application—must include under nails, all body folds, and up to edge of all orifices; include scalp/face in infants. 2, 5
• Using lindane in contraindicated populations (children <10 years, pregnant women, extensive dermatitis) or after bathing. 1, 2, 3
• Not repeating ivermectin at 2 weeks—essential for complete eradication. 1, 2
• Expecting immediate symptom resolution—pruritus normally persists up to 2 weeks and does not indicate treatment failure. 1, 2, 6
• Premature retreatment based on persistent itching alone without demonstrating live mites. 2, 3