Pinworm infection

Pinworm infection is the most common type of intestinal worm infection in the United States. Pinworms are thin and white, measuring about 1/4 to 1/2 inch (about 5 to 13 millimeters) in length.

While the infected person sleeps, female pinworms lay thousands of eggs in the folds of skin surrounding the anus. Most people infected with pinworms have no symptoms, but some people experience anal itching and restless sleep.

Pinworm infection occurs most often in school-age children, and the microscopic eggs are easily spread from child to child. Treatment involves oral drugs that kill the pinworms and thorough washing of bedclothes, bed linens and underwear. For best results, the entire family should be treated.

Symptoms Causes Risk factors Complications Prevention Prevention

Symptoms of pinworm infection may include:

  • Itching of the anal or vaginal area
  • Insomnia, irritability and restlessness
  • Intermittent abdominal pain and nausea

Some people with pinworms have no symptoms.

When to see a doctor

Consult your doctor if you have mild abdominal pain along with insomnia or irritability, or if you're experiencing consistent or severe anal or vaginal itching.

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