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
• Sulfur 6% ointment applied nightly for 3 consecutive nights is a safe alternative for pregnant women and infants, though less cosmetically acceptable. 8
• Benzyl benzoate 25% lotion and malathion 0.5% aqueous lotion are additional alternatives. 7

Special Situation: Crusted (Norwegian) Scabies

Combination therapy is mandatory for crusted scabies 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 includes immunocompromised patients and debilitated elderly who may present atypically without pruritus. 2

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 single most common cause of treatment failure. 2
• Use a 2-month look-back period for sexual partners. 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
• Vacuum furniture and carpets; isolate non-launderable items for minimum 2 days (or 3 weeks for rigorous approach). 5
• Fumigation of living areas is unnecessary. 8, 1
• Mites survive on clothing up to 4 days but only 1-2 days at room temperature. 2

Follow-Up and Persistent Symptoms

Expected Post-Treatment Course

• Rash and pruritus commonly persist for up to 2 weeks after successful treatment—this is NOT treatment failure and does NOT require retreatment. 1, 2, 3
• In clinical trials, approximately 75% of patients with persistent pruritus at 2 weeks had complete resolution by 4 weeks. 6

Indications for Retreatment

• Retreatment is indicated only if symptoms persist beyond 2 weeks AND live mites are demonstrated. 1, 2, 3
• Evaluate patients after 1-2 weeks if symptoms persist to distinguish treatment failure from normal post-treatment reaction. 8, 1
• Consider retreatment at day 4 based on the scabies life cycle to ensure more efficient mite eradication. 5

Critical Pitfalls to Avoid

These errors lead to the majority of treatment failures: 2, 5

1. Not treating all close contacts simultaneously—the leading cause of treatment failure 2
2. Inadequate topical application—must include under fingernails, all body folds, and up to the edge of all orifices; in infants, must include scalp and face 2, 5
3. Using lindane after bathing—dramatically increases absorption and neurotoxicity risk 2
4. Not repeating ivermectin dose at 2 weeks—essential for complete eradication 2
5. Expecting immediate symptom resolution—pruritus normally persists up to 2 weeks after successful treatment 2, 6
6. Failure to decontaminate fomites—bedding, clothing, and furniture must be properly cleaned 5
7. Misinterpreting persistent symptoms as treatment failure—leading to unnecessary repeated treatments and potential toxicity 1, 2

Institutional Outbreaks

• Control of epidemics requires treatment of the entire population at risk simultaneously. 8
• Mass treatment can be performed with single-dose oral ivermectin 200 μg/kg. 7
• Manage in consultation with an infectious disease or public health expert. 8