What is the recommended treatment for pinworms?

Treatment of Pinworm Infection (Enterobiasis)

The first-line treatment for pinworm infection is a single dose of mebendazole (100 mg), pyrantel pamoate (11 mg/kg, maximum 1 g), or albendazole (400 mg), with a repeat dose in two weeks to prevent reinfection. 1, 2, 3, 4

Medication Options and Efficacy

First-line Treatments:

• Mebendazole: 100 mg as a single dose

  • Efficacy: 95% cure rate 2
  • Both adulticidal and ovicidal 4
  • Available as tablets

• Pyrantel pamoate: 11 mg/kg (maximum 1 g) as a single dose

  • Adulticidal but not ovicidal 4
  • Preferred for pregnant women 1, 4
  • Available as oral suspension 3

• Albendazole: 400 mg as a single dose

  • Both adulticidal and ovicidal 4
  • Recommended by the American Society of Tropical Medicine and Hygiene for most intestinal helminths 1

Alternative Treatment:

• Ivermectin: 200 μg/kg as a single dose
  • Useful for resistant cases or when first-line treatments are contraindicated 1, 5

Treatment Protocol

1. Initial treatment: Administer one of the first-line medications as a single dose
2. Repeat treatment: Give a second dose 2 weeks after initial treatment to kill newly hatched worms 4
3. Household treatment: All household members should be treated simultaneously to prevent reinfection 3, 4, 6

Diagnostic Considerations

• Gold standard: Cellophane tape test (50% sensitivity for a single test, increasing to 90% when performed on three consecutive mornings) 1, 4
• Note: Stool examination is not recommended as pinworms and eggs are not usually passed in stool 4

Special Populations

• Pregnant women: Pyrantel pamoate is preferred; avoid mebendazole and albendazole if possible, especially during the first trimester 1, 4
• Children under 2 years: Consult a doctor before administering medication 3

Prevention and Hygiene Measures

Implement the following measures to prevent reinfection:

• Frequent handwashing with soap, especially after using the toilet and before eating 1, 4
• Regular changing and washing of bedding, underwear, and pajamas 4
• Daily showers or baths, preferably in the morning to remove eggs deposited overnight 4
• Keep fingernails short and discourage nail-biting and finger-sucking 4, 6
• Clean toilet seats and bathroom surfaces regularly 4

Common Pitfalls and Caveats

1. Failure to treat all household members can lead to continuous reinfection cycles 4, 6

2. Inadequate hygiene measures alongside medication reduces treatment success 1, 4

3. Missing the second dose after 2 weeks may allow newly hatched worms to mature and restart the infection cycle 4

4. Persistent symptoms after treatment may indicate:

   • Reinfection
   • Treatment failure
   • Alternative diagnosis
   • Consider follow-up evaluation if symptoms persist 1

5. Recurrent infections may require a prolonged "pulse scheme" treatment for up to 16 weeks in severe cases 6

For persistent or recurrent infections despite appropriate treatment, consider consulting with an infectious disease specialist to evaluate for potential resistance or alternative diagnoses.