When your childs bottom itches: What you should know as a parent about pinworms
- Johanna
- Jun 16
- 7 min read
Updated: Jun 23
Pinworms (Enterobius vermicularis) are very common in children and respond well to treatment. With the right knowledge, you can effectively treat your child and prevent re-infection.
An infection with pinworms is not a matter of poor hygiene. The eggs are ubiquitous, especially in communal settings. Open communication, factual information, and consistent action will help your child and your family quickly regain health.
What are pinworms?
Pinworms are white, thread-like roundworms, approximately 0.5 to 1 cm long. They live exclusively in the human large intestine. At night, fertile females migrate to the anus and lay their eggs there. This is precisely what causes the typical itching around the anus.
More than one billion people worldwide are affected.
In Europe, around 20% of kindergarten and primary school children become infected.
In Germany, studies show infestation rates of 2 to 30 percent, depending on the region.
Children aged 4-11 years are most commonly affected, with nail biting and uncontrolled anal-finger-mouth contact being important risk factors.
How do you get infected?
Pinworms spread through fecal-oral smear infection :
If your infectet Child scratches their bottom, tiny eggs get under their fingernails.
The eggs are robust and can survive for up to three weeks on surfaces such as bedding, toys or doorknobs.
If they are transported back into the mouth via the hands, the cycle starts again.
Children can become infected again and again; this is called autoinfection.
Pinworms spread rapidly, especially in daycare centers, schools, or larger family households.
Can parents become infected?
Yes, adults can also become infected , especially through close contact in everyday life. Parents, siblings, and caregivers are particularly affected. In adults, infection often has few symptoms.
Symptoms - How do you know if your child has threadworms?
The most important indicator is nighttime itching of the anus . Other signs may include:
Restless sleep and morning fatigue
Abdominal pain, bloating, nausea or constipation
Teeth grinding and occasional bedwetting
Visible white worms in underwear or stool
What happens in the body?
Ingestion of the eggs through the mouth and swallowing
Eggs hatch in the small intestine
Larvae migrate to the large intestine, where they continue to develop
After about four weeks they become sexually mature; at night females migrate to the anus
Egg laying and subsequent death of the female
Cycle starts again with new ingestion of eggs
In rare cases worms can also migrate into the genital area or beyond – but this remains exceptional.
In rare cases, worms can also migrate into the genital area or beyond, but this remains the exception.
How are pinworms detected?
Discovering the worms is the best evidence, otherwise most doctors focus on the symptoms.
The most reliable method of detection, although rarely performed, is the so-called adhesive strip test. In this test, a transparent adhesive strip is pressed onto the skin around the anus in the morning, before washing or using the toilet, and then examined under a microscope in the laboratory. Since egg laying does not occur daily, it is recommended to perform the test on three consecutive days. This increases the sensitivity to over 90 percent. Stool samples, on the other hand, are usually not suitable.
When should you contact your pediatrician?
If worms are definitely detected , i.e., if they are seen, it is recommended that they be treated with medication . In most cases, however, your child does not need to visit a pediatrician's office . This depends on the symptoms and how your practice handles the case. It's best to contact them, explain the situation, and discuss it. The practice can usually write you a prescription for worm medication and offer advice, usually right over the counter .
There are also over-the-counter remedies available at pharmacies, but these only work on the worms, not the eggs . See 9. Treatment.
Contacting a pediatrician’s office is useful in the following cases:
nighttime itching of the anus
visible worms in the stool or on the underwear
persistent symptoms despite treatment
What happens if you don't treat pinworms?
If left untreated, pinworms can multiply in the intestines for weeks or months. This can create a persistent cycle, especially in children who frequently put their fingers in their mouths. This usually doesn't lead to serious health consequences . However, the symptoms can be very unpleasant and place a significant strain on family life.
Therefore, even if pinworms are not medically threatening, it is advisable to treat the infection promptly, not only to alleviate the symptoms, but also to avoid infection in everyday family or group life and reinfection.
Treatment
For the treatment of pinworms there are in Germany so far no guidelines or standards for doctors to follow. However, there are recommendations, for example from the German Society for Pediatric Infectiology. The choice of medications is based on many years of experience in clinical practice, although the data are limited. Many recommendations come from older studies with small case numbers. Although newer data show high efficacy for mebendazole and similar drugs, large randomized trials specifically in children are often lacking.
This means: treatment is guided by empirical experience, international recommendations, and plausibility. That does not make it any less reasonable, but parents should know that this leads to differing recommendations, for instance regarding drug dosage. The manufacturer of mebendazole-containing medications (e.g. Vermox) recommends taking two tablets daily for three days. However, the German Society for Pediatric Infectiology advises that a single tablet is sufficient.
Conclusion: the combination of established medication and consistent hygiene is currently the best approach. The challenge is not the initial therapeutic success, but the prevention of reinfection.
1. Drug treatment
Frequently used remedies are:
Mebendazole (e.g., Vermox). For ages 2 and up. This medication requires a prescription. Effective against adult worms and their eggs (ovocidal). 1 x 100 mg.
Pyrvinium embonate (e.g., Molevac). From 4 months. Over-the-counter. Not ovocidal, only effective against adult worms. May discolor stools. Dosage is calculated based on body weight.
The second dose after 14 days is usually always recommended , for a clear reason: if eggs are still present in the body or in the environment after the first dose, new worms can hatch from them in the following days and the infection starts again.
Therefore, the following is recommended as standard:
1. Ingestion : eliminates the adult worms
2. Intake after 14 days : eliminates the newly hatched worms before they can lay eggs again
In case of persistent or recurring infestation - contact your doctor's office
Use of a pulse regimen with mebendazole:
100 mg every two weeks for 16 weeks
also recommended for household members without symptoms
Goal: Interruption of the infection cycle
This strategy is especially recommended for recurrent infections despite hygiene and repeated standard treatment (Wendt et al., 2019).
2. Accompanying hygiene measures
Without consistent hygiene, pinworms often recur. Scientific literature reports relapse rates of up to 75 percent when treated with medication alone. The following measures are recommended:
Shower in the morning or wash bottom with warm water
Change underwear, sleepwear and bed linen daily and wash at least 60 degrees
Cut nails short and clean them regularly
Wash hands thoroughly, especially after using the toilet and before eating
Wash stuffed animals regularly
Regularly wipe and vacuum floors, toilets, light switches and door handles
Do not shake out bed linen and clothing
If possible, do not sleep together in bed until treatment is completed
Involve all household members
Hygiene is particularly important during the first week after taking medication, as this is the time when the risk of reinfection is highest.
Why should the family be treated?
Pinworms spread very quickly, especially in close quarters. The tiny eggs stick easily: to shared toilets, bedding, clothing, or toys, and especially to the hands, for example, through nail biting.
Even if not all family members are itchy or have symptoms, they may already be infected or soon become infected. If you only treat your child, siblings or parents often remain unnoticed as spreaders – and the child continues to become re-infected.
Specialist studies show that without simultaneous treatment and consistent hygiene, up to three-quarters of all family members experience a relapse.
Therefore, always treat all close contacts at the same time, including parents, siblings, and caregivers, even if no one is showing symptoms. This breaks the cycle of infection, protects the entire family, and ensures the long-lasting effects of the treatment.
How long does it take for the infection to go away?
With the right combination of treatment and hygiene, the symptoms usually disappear within a few days . However, the hygiene routine should be maintained for at least two weeks , as eggs can survive that long.
A follow-up visit to the pediatrician's office is usually not necessary , except in cases of persistent disease or relapse. If symptoms persist after two treatment cycles, it is advisable to consult a pediatrician.
Does my child have to stay at home?
Not usually . Children with pinworms may continue attending daycare or school if treatment has begun, hygiene measures are in place , and no other symptoms such as fever or diarrhea are present. According to the Infection Protection Act, there is no reporting requirement , but handling the situation respectfully is important to protect other families.
Further knowledge: Overview of worm diseases
In addition to pinworms, there are other worm diseases that can affect humans:
Roundworms (ascariasis): Transmitted through contaminated soil or food, typically in tropical regions. They can grow large and cause abdominal pain or intestinal obstruction.
Whipworms (Trichuriasis): Rarer in Europe. Severe infestation may cause diarrhea, abdominal cramps, and bloody stools.
Hookworms (ankylostomiasis): Penetrate through the skin, e.g., when walking barefoot. Can cause anemia.
Strongyloidiasis: Common in tropical regions. Dangerous for people with weakened immune systems.
Tapeworms (taeniasis): Contained via raw or undercooked meat. Depending on the species, dangerous complications such as brain cyst formation (in pork tapeworms) can occur.
Status: 06/2025
Resources:
German Society for Pediatric Infectious Diseases (DGPI) et al.: 2018
DGPI Handbook. Part 4: Pathogen-Related Diseases. 67 Enterobiasis.
DOI: 10.1055/b-0038-151170
Wendt S, Trawinski H, Schubert S, Rodloff AC, Mössner J, Lübbert C. Diagnosis and treatment of threadworm infestation. Deutsches Ärzteblatt. 2019; 116(13): 213–219. DOI: 10.3238/arztebl.2019.0213
Centers for Disease Control and Prevention (CDC). Parasites - Enterobiasis (also known as Pinworm Infection) . 2020.
Rawla P, Sharma S. Enterobius Vermicularis . In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2021.
