Treatment of Pinworm in a 27-Year-Old Adult
The drug of choice for treating pinworm (Enterobius vermicularis) infection in a 27-year-old adult is either mebendazole 100 mg or albendazole 400 mg as a single oral dose, with a mandatory repeat dose in 2 weeks. 1, 2
First-Line Treatment Options
Both medications are equally effective and recommended by major guidelines:
- Mebendazole 100 mg as a single oral dose is FDA-approved for pinworm treatment with a 95% cure rate 3
- Albendazole 400 mg as a single oral dose achieves 100% cure rates in clinical trials 1, 4
- The tablet may be chewed, swallowed, or crushed and mixed with food for either medication 3
Critical Dosing Requirements
The repeat dose at 2 weeks is essential and non-negotiable:
- The second dose kills newly hatched worms from eggs that were present during initial treatment 1, 2
- This prevents reinfection and ensures complete eradication 1
- No special procedures such as fasting or purging are required 3
Clinical Context
The most common presentation includes:
- Nocturnal perianal itching is the hallmark symptom 1, 2
- Other symptoms may include weight loss, irritability, diarrhea, and abdominal pain 1
- In females, vaginal discharge may occur from genital tract colonization 1, 2
- However, 30-40% of infected individuals remain asymptomatic 2
Important Pitfalls to Avoid
- Do not skip the 2-week repeat dose - this is the most common cause of apparent treatment failure 1, 2
- Persistent symptoms after treatment usually indicate reinfection rather than medication resistance 2
- Consider treating household contacts simultaneously to prevent reinfection cycles 5
- The cellophane tape test (performed in the morning before bathing) confirms diagnosis, as pinworms and eggs are not usually passed in stool 1, 2
Choosing Between Mebendazole and Albendazole
Both medications are equally effective with standardized dosing across all age groups 2, 4: