What is the recommended treatment for scabies?

Scabies Treatment

Permethrin 5% cream is the first-line treatment for scabies, applied from head to toe and left on for 8-14 hours, with one application generally being curative. 1, 2

First-Line Treatment

• Permethrin 5% cream:
  • Apply thoroughly from head to toe (including scalp, hairline, neck, temple, and forehead in infants and elderly)
  • Leave on for 8-14 hours before washing off
  • Usually 30 grams is sufficient for an average adult
  • Cure rate: 89-95% at 4 weeks after treatment 1
  • Safe for use during pregnancy and lactation 1
  • Considered treatment of choice by the CDC and American Academy of Pediatrics 1

Treatment Protocol

1. Application technique:

   • Thoroughly massage cream into skin from head to soles of feet
   • Pay special attention to areas between fingers and toes, wrists, axillae, external genitalia, and buttocks
   • For infants, include scalp, temple, and forehead in treatment 2

2. Treatment duration:

   • ONE APPLICATION IS GENERALLY CURATIVE 2
   • Remove by washing (shower or bath) after 8-14 hours

3. Special populations:

   • Children under 2 years: Permethrin 5% is recommended as first option
   • Some experts suggest using permethrin 2.5% for children under 5 years 1

Alternative Treatments

When permethrin fails or is not tolerated:

• Oral ivermectin:

  • Dosage: 200 μg/kg, repeated after 14 days
  • Particularly useful for crusted scabies (combined with topical treatment) 1, 3
  • Single dose provides cure rate of 62.4%, increasing to 92.8% with second dose 4

• Other alternatives:

  • Topical ivermectin 0.8%
  • Benzyl benzoate 25% lotion
  • Malathion 0.5% aqueous lotion
  • Sulphur 6-33% cream/ointment/lotion 3

Management of Contacts and Environment

• Contact treatment:

  • Treat all household members and close contacts simultaneously, even if asymptomatic
  • For pediculosis pubis, treat sexual partners from the past month 1

• Environmental measures:

  • Wash laundry and clothing in hot water and dry on hot cycle
  • Alternatively, keep items out of body contact for at least 72 hours
  • Fumigation of living areas is NOT necessary 1

Follow-up and Retreatment

• Post-treatment evaluation:

  • Evaluate after 1 week to assess treatment response
  • Persistent pruritus after treatment is common and rarely indicates treatment failure
  • Retreatment is indicated ONLY if live mites are still present after 14 days 1, 2

• Monitoring:

  • Pruritus may persist for several weeks after successful treatment
  • This is not an indication for retreatment unless living mites are demonstrated 2

Special Considerations

• Impetiginized scabies:

  • Consider combination therapy with permethrin 5% and fusidic acid 2% cream for better outcomes (95% vs 35% efficacy at 14 days) 5
  • Staphylococcus aureus is the most common bacterium causing secondary infection 5

• Treatment optimization:

  • Some research suggests applying permethrin as cold cream (refrigerated) for two consecutive days may be more effective than single application (87.2% vs 61.8% cure rate) 6

Common Pitfalls

1. Retreating too soon - Persistent itching after treatment is common and not necessarily a sign of treatment failure
2. Failing to treat all contacts - Simultaneous treatment of all household members is essential to prevent reinfection
3. Overusing medications - One application of permethrin is generally curative; unnecessary retreatment can lead to skin irritation
4. Inadequate application - Ensure complete coverage from head to toe, especially in skin folds and between digits

Remember that proper application technique and treatment of all contacts are as important as the choice of medication for successful eradication of scabies.