What is the recommended treatment for scabies?

Scabies Treatment

For uncomplicated scabies, use topical permethrin 5% cream as first-line treatment, applied from the neck down for 8-14 hours, with oral ivermectin 200 μg/kg (repeated in 2 weeks) as an equally effective alternative for adults and children ≥15 kg. 1, 2

First-Line Treatment Options

Topical Permethrin 5% Cream

• Apply to all areas of the body from the neck down (including under fingernails, between fingers and toes, and all skin folds), leave on for 8-14 hours, then wash off 3, 1
• One application is generally curative, though a second application 7-10 days later is recommended to ensure eradication 3, 4
• More effective when applied for two consecutive days (87.2% cure rate) compared to single application (61.8% cure rate) 4
• Preferred for infants, young children, pregnant women, and lactating women due to superior safety profile 1, 2
• Safe and effective in children ≥2 months of age 5

Oral Ivermectin

• Dose: 200 μg/kg orally, repeated in 2 weeks 3, 1, 2
• Must be taken with food to increase bioavailability and epidermal penetration 3, 2
• Contraindicated in children weighing <15 kg due to neurotoxicity risk 1, 6
• Avoid in pregnant and lactating women due to limited safety data 1, 6
• No dosage adjustment needed for renal impairment, but safety uncertain with severe liver disease 3
• Particularly useful for institutional outbreaks and when treating large numbers of patients simultaneously 7, 8

Special Populations

Pregnant and Lactating Women

• Use permethrin 5% cream exclusively 1, 6
• Permethrin is FDA Pregnancy Category B with no evidence of fetal harm in animal studies 5
• Avoid ivermectin due to insufficient human safety data 1, 6

Infants and Young Children

• Permethrin 5% cream is the treatment of choice 3, 1
• Safe in infants ≥2 months of age 5
• Never use lindane in children <10 years due to neurotoxicity risk 3, 2
• Avoid ivermectin in children weighing <15 kg 1, 6

Crusted (Norwegian) Scabies

• Requires combination therapy: 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 1, 2
• This severe form occurs primarily in immunocompromised patients and requires aggressive treatment 2, 9

Alternative Treatments (When First-Line Options Fail or Are Contraindicated)

• Lindane 1% lotion or cream: Apply for 8 hours, but avoid in children <10 years, pregnant/lactating women, and patients with extensive dermatitis due to neurotoxicity risk including seizures and aplastic anemia 3, 2, 6
• Never apply lindane immediately after bathing, as this increases systemic absorption and toxicity 3, 2
• Lindane resistance has been reported in some geographic areas 3

Contact and Environmental Management

Contact Tracing and Treatment

• Examine and treat all close personal, sexual, and household contacts within the preceding month, even if asymptomatic 1, 2, 6
• Failure to treat contacts simultaneously is the most common cause of treatment failure 6
• Avoid sexual and close physical contact until patients and all contacts complete treatment 3

Environmental Decontamination

• Machine wash and dry bedding and clothing using hot cycle, or dry clean 3, 1, 2
• Alternatively, remove items from body contact for at least 72 hours 3, 2, 6
• Fumigation of living areas is unnecessary 3, 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 and do not indicate treatment failure 1, 2, 6
• Approximately 75% of patients with persistent pruritus at 2 weeks will have resolution by 4 weeks 5

When to Retreat

• Consider retreatment only after 2 weeks if symptoms persist AND live mites are observed 1, 2, 6
• Reasons for persistent symptoms include: treatment failure, reinfection from untreated contacts, inadequate application, and cross-reactivity with other household mites 2

Critical Pitfalls to Avoid

• Failing to apply permethrin to all body areas, especially under fingernails, between toes, and in all skin folds 6, 10
• Not treating all household and close contacts simultaneously, leading to reinfection 6
• Forgetting to repeat ivermectin dose at 2 weeks, as it has limited ovicidal activity 3, 6
• Using lindane after bathing or showering, which dramatically increases systemic absorption and neurotoxicity risk 3, 2
• Expecting immediate symptom resolution and retreating unnecessarily within the first 2 weeks 1, 2
• Using lindane in contraindicated populations (children <10 years, pregnant/lactating women, extensive dermatitis) 3, 2, 6

Secondary Bacterial Infections

• Staphylococcus aureus and Streptococcus pyogenes are the most common secondary bacterial infections in scabies 9, 11
• When impetiginization is present, combination of permethrin 5% with fusidic acid 2% cream is more effective than permethrin alone (95% vs 35% cure rate at day 14) 11
• Secondary bacterial infections are responsible for scabies-related mortality, particularly in resource-limited settings 9