Pinworm Treatment
Treat pinworm infection with a single oral dose of either albendazole 400 mg or mebendazole 100 mg, repeated in 2 weeks, regardless of patient age. 1
First-Line Treatment Options
Both medications are equally effective and safe across all age groups, including young children as young as 2 years old:
- Albendazole 400 mg as a single oral dose, repeated in 2 weeks 1
- Mebendazole 100 mg as a single oral dose, repeated in 2 weeks 1, 2
- Pyrantel pamoate 11 mg/kg (maximum 1 gram) as a single dose, repeated in 2 weeks 3, 4
The American Academy of Pediatrics recommends albendazole or mebendazole as preferred agents, with standardized dosing that does not vary by age 1. Mebendazole achieves cure rates of approximately 95% for pinworm infection 2. Both albendazole and mebendazole are adulticidal and ovicidal, while pyrantel pamoate is only adulticidal 4.
Why Two Doses Are Essential
The repeat dose at 2 weeks is critical to eradicate any newly hatched worms from eggs that survived the initial treatment 1. This timing corresponds to the pinworm life cycle and prevents treatment failure.
Household Treatment Strategy
Treat all household members simultaneously, especially when there are multiple or repeated symptomatic infections, as reinfection is extremely common. 4, 5 The involvement of all persons living in the household, including sexual partners, is a prerequisite to lasting treatment success 5.
Clinical Presentation to Recognize
- Nocturnal perianal itching is the most common symptom 1
- 30-40% of infected children are completely asymptomatic 1
- Other symptoms include weight loss, irritability, diarrhea, and abdominal pain 1
- In girls, vaginal discharge may occur from female genital tract colonization 1
Diagnostic Confirmation
Use the cellophane tape test (sticky side applied to perianal skin in the morning before bathing) for diagnosis 1. A single test has only 50% sensitivity, but performing the test on three consecutive mornings increases sensitivity to approximately 90% 4. Do not examine stool samples, as pinworms and eggs are not usually passed in stool 1.
Special Population: Pregnancy
For pregnant women, pyrantel pamoate is preferred over mebendazole and albendazole due to safety considerations 4.
Treatment Failure vs. Reinfection
Persistent symptoms after treatment almost always indicate reinfection rather than medication resistance. 1 Treatment failure with these medications is rare. Recurrences are common due to repeated cycles of autoinfection, given the short life span of adult pinworms and ease of transmission 4.
Safety Monitoring
Monitor for hepatotoxicity and leukopenia only if treatment extends beyond 14 days, which would be unusual for pinworm infection 1. Standard two-dose treatment does not require laboratory monitoring.
Prevention Measures to Emphasize
- Frequent handwashing, especially after bowel movements and before meals 4
- Clipping fingernails short 4
- Avoiding finger-sucking, nail-biting, and scratching the anogenital area 4
- Daily morning bathing to remove eggs deposited overnight 5
Common Pitfall to Avoid
Do not treat only the symptomatic individual—this leads to rapid reinfection from untreated household members who may be asymptomatic carriers 4, 5. The entire household must be treated as a unit for successful eradication.