What is the recommended treatment for pinworms?

Pinworm Treatment

The recommended first-line treatment for pinworm infection is either albendazole 400 mg or mebendazole 100 mg as a single oral dose, with a mandatory repeat dose in 2 weeks to eradicate newly hatched worms. 1, 2

First-Line Medication Options

Both medications are equally effective and endorsed by major medical societies:

• Albendazole 400 mg as a single oral dose, repeated in 2 weeks 1, 2
• Mebendazole 100 mg as a single oral dose, repeated in 2 weeks 1, 2, 3

The FDA label confirms mebendazole achieves a 95% cure rate for pinworm infection 3. Both albendazole and mebendazole are adulticidal (kill adult worms) and ovicidal (kill eggs), making them superior to alternatives 4.

Alternative Option

• Pyrantel pamoate 11 mg/kg (maximum 1 gram) as a single dose, repeated in 2 weeks 5, 4
  • This is only adulticidal, not ovicidal, making it less effective than the benzimidazoles 4
  • Preferred in pregnancy when benzimidazoles should be avoided 4
  • Available over-the-counter 5

Critical Treatment Principles

The 2-week repeat dose is mandatory, not optional 1, 2. This timing corresponds to the pinworm life cycle and ensures elimination of worms that were eggs during the first treatment.

Treat all household members simultaneously, especially with multiple or recurrent symptomatic infections, as reinfection is extremely common 4, 6. The entire household should be treated even if only one person is symptomatic 5.

Recurrent or Refractory Infections

For persistent infections despite standard treatment:

• Consider a "pulse scheme" with prolonged treatment for up to 16 weeks 6
• Ensure strict adherence to hygiene measures alongside medication 6
• Verify compliance with the 2-week repeat dose 1

Essential Hygiene Measures

Medication alone is insufficient without concurrent hygiene interventions 4, 6:

• Frequent handwashing, especially after bowel movements and before meals 4
• Clip fingernails short 4
• Avoid nail-biting, finger-sucking, and scratching the perianal area 4
• Morning bathing to remove eggs deposited overnight 4
• Daily changing of underwear and bed linens 6

Diagnostic Confirmation

The cellophane tape test (sellotape test) is the preferred diagnostic method 1, 2. Apply adhesive tape to the perianal skin in the morning before bathing or defecation to collect eggs 2. A single test has only 50% sensitivity, but three tests performed on consecutive mornings increase sensitivity to approximately 90% 4.

Common Clinical Presentations

• Nocturnal perianal itching is the most common symptom 1, 2
• Other manifestations include weight loss, irritability, diarrhea, and abdominal pain 1, 2
• In females, vaginal discharge may occur from genital tract colonization 1, 2
• Approximately 30-40% of infected patients are asymptomatic 4

Common Pitfall

The most frequent treatment failure is not repeating the dose at 2 weeks or failing to treat all household contacts simultaneously, leading to rapid reinfection cycles 4, 6.