Threadworms coming out of the bottom: what to know

Threadworms, also called pinworms, live in the bowel. At night, adult worms may move to the skin around the anus to lay eggs. They can look like fine, white pieces of thread and may move. Itching is common and can disturb sleep. Scratching can transfer eggs to fingers, clothing, bedding and household surfaces, allowing infection to pass between people. Abdominal pain is not a defining feature, so marked or persistent pain needs separate assessment.

Speak with a pharmacist or clinician about a suitable worm treatment, especially for a young child, pregnancy or breastfeeding. Usually, household members may need coordinated advice because reinfection is easy. Wash hands carefully after using the toilet and before eating; keep fingernails short; shower in the morning; change underwear and sleepwear; and wash bedding and towels regularly. Avoid shaking fabrics, and clean frequently touched bathroom surfaces. Follow the product instructions, including any advice about a repeat dose.

Arrange a GP consultation if symptoms continue after treatment, keep returning, or the diagnosis is uncertain. Seek prompt care for severe abdominal pain, vomiting, a swollen abdomen, blood in the stool, marked weakness or signs of dehydration. A child with sleep disruption, persistent scratching or bedwetting may need an assessment of the wider problem rather than repeated self-treatment.

Ask which product suits the person's age, whether other household members should be treated, when a repeat dose is needed, and how long hygiene measures should continue. Mention previous treatments, ongoing itching and any abdominal symptoms.