What is the recommended treatment for scabies?

Scabies Treatment

Permethrin 5% cream applied to all areas of the body from the neck down and washed off after 8-14 hours is the recommended first-line treatment for uncomplicated scabies, with oral ivermectin 200 μg/kg (repeated in 2 weeks) as an equally effective alternative. 1, 2, 3

First-Line Treatment Options

Topical Permethrin 5%

• Apply from the neck down to all body areas, leave on for 8-14 hours, then wash off 1, 2
• One application is generally curative in most cases 3
• More effective and less expensive than ivermectin, with excellent safety profile 1
• Preferred for infants, young children, pregnant women, and lactating women 1, 2, 3
• Safe for pediatric patients ≥2 months of age 4

Important caveat: Recent high-quality evidence from 2024 shows permethrin may have reduced efficacy, with only 27% cure rate in one randomized controlled trial, compared to 87% for benzyl benzoate 25% 5. This suggests potential emerging resistance, though guidelines still recommend permethrin as first-line based on historical data and broader evidence base.

Oral Ivermectin

• Dose: 200 μg/kg orally, repeated in 2 weeks 1, 2
• Must be taken with food to increase bioavailability and epidermal penetration 1, 2
• The second dose at 2 weeks is essential because ivermectin has limited ovicidal activity 1, 2
• Contraindicated in children weighing <15 kg due to neurotoxicity risk 2, 3
• No dosage adjustments needed for renal impairment, but safety uncertain in severe liver disease 1
• Not recommended for pregnant or lactating women due to limited safety data 2, 3

Alternative Regimens (Use Only If First-Line Options Fail or Cannot Be Tolerated)

Lindane 1%

• Apply thin layer from neck down, wash off after 8 hours 1
• Should be avoided due to neurotoxicity risk 1, 2, 3
• Absolute contraindications: children <10 years, pregnant/lactating women, persons with extensive dermatitis 1, 2, 3
• Never apply immediately after bathing—this increases absorption and seizure risk 1, 2
• Resistance reported in some geographic areas 1

Benzyl Benzoate 25%

• Emerging evidence shows 87% cure rate vs. 27% for permethrin in head-to-head trial 5
• Causes burning sensation in 43% of patients but demonstrates excellent efficacy 5
• May be considered when permethrin fails, though not included in CDC guidelines 5

Special Population: Crusted (Norwegian) Scabies

Requires aggressive combination therapy—single-agent treatment will fail 2, 3

• Topical permethrin 5% cream applied daily for 7 days, then twice weekly until cure 2, 3
• PLUS oral ivermectin 200 μg/kg on days 1,2,8,9, and 15 2, 3
• This intensive regimen addresses the massive mite burden (thousands to millions of mites) 2
• Single-application permethrin or single-dose ivermectin will fail 2
• Never use lindane in this population—patients are often immunocompromised and vulnerable to neurotoxicity 2

Contact and Environmental Management

Contact Tracing and Treatment

• Examine and treat all persons with sexual, close personal, or household contact within the preceding month 2, 3
• Treat contacts simultaneously even if asymptomatic—failure to do so is the most common cause of treatment failure 2, 6

Environmental Decontamination

• Machine wash and dry bedding/clothing using hot cycle, or dry clean 1, 2, 3
• Alternative: Remove items from body contact for at least 72 hours 1, 2, 6
• Fumigation of living areas is unnecessary 1, 2, 6

Follow-Up and Management of Persistent Symptoms

Expected Post-Treatment Course

• Pruritus, rash, and erythema may persist for up to 2 weeks after successful treatment—this does NOT indicate treatment failure 2, 3, 4
• Approximately 75% of patients with pruritus at 2 weeks will have resolution by 4 weeks 4

When to Retreat

• Consider retreatment only if symptoms persist beyond 2 weeks AND live mites are observed 2, 3
• Reasons for persistent symptoms include: treatment failure, reinfection from untreated contacts, inadequate application, or cross-reactivity with other household mites 2

Critical Pitfalls to Avoid

1. Inadequate application of topical treatments—must apply to ALL areas from neck down, including under fingernails and all body folds 2, 6

2. Failing to treat all close contacts simultaneously—this is the leading cause of treatment failure and reinfection 2, 6

3. Not repeating ivermectin dose at 2 weeks—essential for complete eradication due to limited ovicidal activity 1, 2

4. Using lindane after bathing or in contraindicated populations—increases absorption and risk of seizures 1, 2

5. Expecting immediate symptom resolution—pruritus commonly persists 1-2 weeks post-treatment 2, 3, 4

6. Retreating too early based on persistent itching alone—wait at least 2 weeks and confirm live mites before retreating 2, 3

7. Using single-application permethrin for crusted scabies—will fail; requires combination therapy 2