It’s a conversation I have more often than you might think. A patient comes into my office feeling just… off. They can’t quite put their finger on it. Maybe it’s a nagging stomach ache, a bit of diarrhea that comes and goes, or just feeling bloated and gassy for weeks. When we start digging, sometimes the answer is an unwelcome visitor. The topic of intestinal parasites can make people feel a little squeamish, but it’s a real and treatable medical issue. Let’s talk about it, honestly and without the fuss.
A parasite is simply any organism that sets up camp in another organism (the host) to live and feed. When this happens in your gut, we call them intestinal parasites. They don’t pay rent, and they certainly don’t help out. Instead, they can cause a range of uncomfortable symptoms and, in some cases, lead to more serious health problems.
What Are Intestinal Parasites, Really?
Think of them in two main groups: helminths, which are worms, and protozoa, which are tiny, single-celled organisms.
Most worms can’t multiply inside your body. Instead, they lay microscopic eggs that pass out in your poop. The infection spreads when someone else unknowingly comes into contact with these eggs. Protozoa, on the other hand, can multiply inside you, which can sometimes lead to more severe infections.
Here’s a quick look at some of the more common culprits we see.
| Type of Parasite | Common Name(s) | How It Spreads |
|---|---|---|
| Helminths (Worms) | ||
| Roundworms | Pinworm, Ascaris, Hookworm | Usually by accidentally swallowing eggs from contaminated hands, food, or soil. Hookworms can also enter through the skin of your bare feet. |
| Flatworms | Tapeworm, Flukes | Often from eating raw or undercooked pork, beef, or fish. Can also come from contaminated water or aquatic plants. |
| Protozoa (Single-Celled) | ||
| Various | Giardia, Cryptosporidium, Entamoeba | These are very common culprits of “traveler’s diarrhea” and often spread through contaminated water—from swimming pools and lakes to drinking water. |
Tummy Troubles and Other Telltale Signs
Not everyone with a parasite has symptoms. You could be a host and not even know it. But when symptoms do show up, they often involve your digestive system.
You might experience:
- Diarrhea that can be watery and persistent.
- Abdominal pain or cramping.
- A lot of gas and bloating.
- Nausea and sometimes vomiting.
- A really frustrating anal itching, especially at night (a classic sign of pinworms).
A common question I get is, “Will I see worms in my poop?” Usually, no. You’re passing eggs that are too small to see without a microscope. The main exception is the tapeworm. Sometimes, segments of its body break off and can look like little white grains of rice in your stool.
How Do These Parasites Get In?
It almost always comes down to accidentally swallowing something contaminated with microscopic eggs from someone’s (or some animal’s) poop. It sounds gross, I know, but it’s the reality.
This can happen by:
- Drinking contaminated water from wells, lakes, rivers, or even poorly maintained pools.
- Eating contaminated food, like unwashed produce or undercooked meat.
- Touching a contaminated surface (like bedding or a bathroom fixture) and then touching your mouth.
- Walking barefoot on contaminated soil where certain larvae, like hookworm, can burrow through your skin.
Your risk is higher if you live in or travel to areas with warm climates, limited access to clean water, and poor sanitation. This includes many tropical and subtropical regions.
Getting a Clear Diagnosis for Intestinal Parasites
If you’re having persistent gut symptoms, please don’t just guess. Come see us. To figure out what’s going on, we’ll start by talking about your symptoms and any recent travel.
From there, the main diagnostic tool is a stool test. You’ll be given a special container to collect a small sample of your poop at home. It’s not anyone’s favorite task, but it’s the best way for the lab to look for parasite eggs or the parasites themselves under a microscope.
Depending on the situation, we might also consider:
- The Scotch™ tape test: This is a simple test for pinworms. You press a piece of clear tape against the skin around the anus first thing in the morning to pick up any eggs. We then look at the tape under a microscope.
- Blood tests: These can sometimes detect signs of an infection, like high levels of certain white blood cells, or antibodies your body has made to fight a specific parasite.
- Imaging: In rare cases, if we suspect worms have caused a blockage or other issues, we might use an X-ray or ultrasound.
Treatment: Showing Parasites the Door
The good news is that we have very effective medications to treat intestinal parasites. Some infections might clear up on their own, but most require a course of antiparasitic drugs to get rid of them for good.
These medications work by either paralyzing the parasites so they can be passed out of your body or by killing them and their eggs directly. The specific drug we prescribe, like albendazole, mebendazole, or metronidazole, depends entirely on which parasite has been identified.
It’s so important to take the medicine exactly as prescribed. Some treatments are a single dose, while others might require several days or even a repeat course after a couple of weeks to ensure all the eggs have been eliminated. Once the medicine does its job, your symptoms should start to fade away.
Take-Home Message
- What They Are: Intestinal parasites are worms or single-celled organisms that live in your gut and can cause a range of digestive symptoms.
- How You Get Them: Most infections happen by accidentally ingesting microscopic eggs from contaminated food, water, or surfaces. Good handwashing is your best defense.
- Key Symptoms: Watch for persistent diarrhea, abdominal pain, gas, bloating, and sometimes anal itching.
- Diagnosis is Key: Don’t guess. A simple stool test is the most common and effective way to identify the specific parasite causing your trouble.
- Treatment Works: Prescription antiparasitic medications are very effective at clearing most intestinal parasites and helping you feel better.
If you’ve been struggling with unexplained gut issues, please know you don’t have to just live with it. It’s a medical condition like any other.
You’re not alone in this, and we’re here to help you get back to feeling like yourself.