What are the best oral and topical treatments for scabies?

Best Treatments for Scabies

For uncomplicated scabies, permethrin 5% cream is the first-line topical treatment, while oral ivermectin (200 μg/kg, repeated in 2 weeks) is the recommended oral medication. 1

Recommended Treatment Options

First-Line Treatments

• Topical Treatment: Permethrin 5% cream applied to all areas of the body from the neck down and washed off after 8-14 hours 1

  • More effective, safer, and less expensive than other options 1
  • Apply to the entire body surface from neck down, paying special attention to skin folds and creases 2
  • Particularly recommended for infants, young children, and pregnant/lactating women 1

• Oral Treatment: Ivermectin 200 μg/kg orally, repeated in 2 weeks 1

  • Should be taken with food to increase bioavailability and penetration into the epidermis 1
  • No dosage adjustments required for patients with renal impairment 1
  • Not recommended for children weighing <15 kg or pregnant women (unless benefits outweigh risks) 1
  • Effective as permethrin in treatment of scabies with comparable cure rates 3

Alternative Treatments

• Lindane (1%): Applied as lotion or cream in a thin layer to all areas from neck down and washed off after 8 hours 1

  • Should only be used if first-line treatments cannot be tolerated or have failed 1
  • Contraindications: 1
    • Children <10 years
    • Pregnant or lactating women
    • Persons with extensive dermatitis
    • Application immediately after bath/shower
  • Associated with serious adverse effects including seizures and aplastic anemia 1
  • Resistance has been reported in some areas of the world, including parts of the United States 1

• Crotamiton: Massage thoroughly into skin from chin down, with particular attention to folds and creases 4

  • A second application is recommended 24 hours later 4
  • Less effective than other options 3

Special Considerations

Crusted (Norwegian) Scabies

• Requires combination therapy: 1
  • Topical scabicide (5% permethrin cream or 5% benzyl benzoate) applied daily for 7 days, then twice weekly until discharge/cure 1
  • PLUS oral ivermectin 200 μg/kg on days 1,2,8,9, and 15 1
  • Severe cases may require additional ivermectin on days 22 and 29 1
  • Lindane should be avoided due to risk of neurotoxicity 1

Special Populations

• Infants and Young Children: Use permethrin; ivermectin safety not established in children <15 kg 1
• Pregnant/Lactating Women: Permethrin is preferred due to limited data on ivermectin safety 1
• HIV-Infected Persons: Same treatment regimens as HIV-negative individuals for uncomplicated scabies 1
• Immunocompromised Patients: Higher risk for crusted scabies; consultation with specialist recommended 1

Management of Contacts and Environment

• Examine and treat all persons who have had sexual, close personal, or household contact with the patient within the preceding month 1
• Decontaminate bedding and clothing by machine washing/drying using hot cycle, dry cleaning, or removing from body contact for at least 72 hours 1
• Keep fingernails closely trimmed to reduce injury from excessive scratching 1

Follow-Up and Treatment Failure

• Rash and pruritus may persist for up to 2 weeks after successful treatment 1
• Consider retreatment after 2 weeks if symptoms persist or live mites are observed 1
• Reasons for persistent symptoms include: 1
  • Treatment failure (resistance or improper application)
  • Reinfection from untreated contacts or fomites
  • Cross-reactivity with other household mites
  • Allergic dermatitis to dead mites

Comparative Efficacy

• Single application of permethrin (97.8% cure rate) is superior to a single dose of ivermectin (70% cure rate) 5
• Two doses of ivermectin (95% cure rate) is comparable to a single application of permethrin 5
• Both topical and oral ivermectin can achieve 100% cure rate when treatment is repeated after one week 6

Treatment Pitfalls to Avoid

• Failure to treat all close contacts simultaneously 1
• Inadequate application of topical treatments (entire body from neck down must be treated) 1
• Using lindane after bathing or in contraindicated populations 1
• Not repeating ivermectin dose after 2 weeks (limited ovicidal activity may not prevent recurrences) 1
• Expecting immediate resolution of symptoms (may take up to 2 weeks for symptoms to resolve) 1