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What Are Intestinal Parasites?
Intestinal parasites include several types of organisms, such as worms and microscopic parasites. Common examples include pinworms, roundworms, tapeworms, hookworms, and Giardia.
Pinworms are especially common in children and households because they spread easily. The CDC explains that pinworm infection often causes itching around the anus, especially at night, and diagnosis may involve looking for worms a few hours after sleep or using a tape test.
Giardia is another intestinal parasite that can spread through contaminated water, food, surfaces, or contact with infected people or animals. Symptoms can include diarrhea, abdominal pain, bloating, nausea, and vomiting.
Common Symptoms of Intestinal Parasites
Symptoms can vary, but possible signs include:
itching around the anus, especially at night
stomach pain or cramps
bloating and gas
diarrhea or constipation
nausea or vomiting
changes in appetite
unexplained fatigue
trouble sleeping
irritability or restlessness
weight changes
visible worms or unusual material in stool
Anal itching at night is one of the most common signs of pinworms. Mayo Clinic notes that pinworm treatment usually involves anti-parasite medicine, and household hygiene is important to prevent reinfection.
Why Symptoms Are Often Confused With Other Problems
Parasite symptoms can look like many other digestive conditions. Bloating, fatigue, diarrhea, constipation, and appetite changes can also be caused by food intolerance, stress, irritable bowel syndrome, stomach infections, medication side effects, or other health issues.
That is why diagnosis matters. A healthcare professional may recommend stool testing, tape testing for pinworms, or other checks depending on the symptoms.
When to See a Doctor
Speak with a healthcare professional if symptoms continue, if several people in the household have itching or digestive symptoms, or if you notice worms in stool or around the anus.
Seek urgent medical help if there is severe abdominal pain, dehydration, blood in stool, persistent vomiting, high fever, unexplained weight loss, severe weakness, or symptoms in a young child, pregnant person, older adult, or someone with a weakened immune system.
What Treatment Usually Involves
Treatment depends on the parasite. Pinworms are often treated with anti-parasite medicines, and Mayo Clinic explains that a second dose is commonly taken two weeks later to kill worms that hatch after the first treatment.
For Giardia, treatment may involve prescription medication, and fluids are important if diarrhea is present. The CDC notes that a healthcare provider may prescribe medicine for Giardia and recommends drinking plenty of fluids during diarrhea.
Do not use leftover medication or guess the treatment. The wrong medicine may not work for the parasite involved.
Hygiene Steps That Help Prevent Reinfection
Hygiene is very important, especially with pinworms because eggs can spread easily. Helpful steps include: