Treatment for Pinworms (Enterobius vermicularis)
First-line treatment for pinworm infection is a single dose of mebendazole 100 mg or albendazole 400 mg, repeated after 2 weeks to kill newly hatched worms and prevent reinfection. 1, 2, 3
Medication Options
- Mebendazole 100 mg as a single oral dose is highly effective with cure rates of approximately 95% 2
- Albendazole 400 mg as a single oral dose is an equally effective alternative 1, 3
- Pyrantel pamoate (11 mg/kg, maximum 1 g) is another option, particularly preferred during pregnancy 4, 3
- All treatments should be repeated after 2 weeks to address the pinworm life cycle and prevent reinfection 1, 3
Mechanism of Action
- Mebendazole and albendazole are both adulticidal (kill adult worms) and ovicidal (kill eggs) 3
- Pyrantel pamoate is only adulticidal, which may impact its effectiveness in preventing reinfection 3
Treatment Considerations
- Treatment of all household members should be considered, especially with multiple or repeated infections, as reinfection is common 3, 5
- For recurrent infections, prolonged treatment for up to 16 weeks using a "pulse scheme" may be necessary 5
- In cases of female genital tract colonization (causing vaginal discharge), the same treatment regimen applies but may require longer duration 1, 6
Hygienic Measures
- Good personal hygiene is essential to prevent reinfection 3, 5:
- Frequent handwashing, especially after bowel movements and before meals
- Clipping of fingernails
- Avoidance of finger-sucking, nail-biting, and scratching in the anogenital area
- Regular changing and washing of undergarments and bedding
Diagnosis
- The cellophane tape test (also called sellotape test) is the preferred diagnostic method 7, 1, 8
- Performed by placing adhesive tape on the perianal skin in the morning before bathing or defecation
- The sensitivity of a single test is around 50%, increasing to approximately 90% when performed on three different mornings 3
- Stool examination is not recommended as pinworms and eggs are not typically passed in stool 8, 3
Clinical Presentation
- Nocturnal perianal itching is the most common symptom 1, 8
- Other symptoms may include weight loss, irritability, diarrhea, abdominal pain, and occasionally colitis with eosinophilia 1, 8
- In females, pinworms may colonize the genital tract, causing vaginal discharge 1, 6