Parasites 101: What You Should Know About These Hidden Invaders

 Medically reviewed by Dr. Dan Wool, NMD

 Arizona-licensed Naturopathic Physician and Gastroenterology Specialist

 Updated: November 11, 2025

Summary: 

• What Are Parasites and How Common Are They?: Parasites include protozoa (like Giardia), helminths (worms), and ectoparasites (lice, fleas) that affect millions in the U.S. annually; higher risk groups include travelers, pet owners, daycare children, immunocompromised individuals, and those consuming raw/undercooked meat or fish.
• Parasite Symptoms: Gut Health Warning Signs: Common symptoms include chronic digestive issues (bloating, gas, diarrhea), unexplained fatigue and brain fog, skin rashes and itching, nutrient deficiencies (iron, B12), weight changes, sleep disturbances, teeth grinding, and mood changes like anxiety—often linked to gut dysbiosis and systemic inflammation.
• Are Parasite Cleanses Legit or Just Social Media Hype?: Most over-the-counter cleanses lack scientific backing and pose risks including diarrhea, dehydration, nutrient loss, and medication interactions; effective treatment requires proper stool testing (CSA+P), professional supervision, and personalized protocols combining herbal antimicrobials with gut healing support—not DIY cleanses from TikTok. Parasite meds are inexpensive, well-studied and work very well. 
• Parasite Prevention and Treatment - Holistic Approach: Prevent infections through hand hygiene, filtered water, thoroughly washing produce, avoiding raw meat/fish, and strengthening gut health with probiotics and fermented foods; treatment combines prescription antiparasitics when needed with naturopathic support including wormwood, black walnut, berberine, anti-inflammatory diet, and detox protocols under qualified healthcare guidance.

What are parasites?

Parasites are organisms that live in or on a host organism and get their nutrients at the expense of the host. They are not just a concern for travelers or people in developing countries, but are a global health issue that can affect anyone, including those living in clean, modern environments. Parasites come in many forms, but there are three main categories to be aware of:

• Protozoa: Single-celled organisms like Giardia lamblia or Entamoeba histolytica, which often cause gastrointestinal infections.
• Helminths: Worm-like parasites such as roundworms, tapeworms, and flukes that can inhabit the intestines or other organs.
• Ectoparasites: External parasites like lice, fleas, and mites that live on the skin or hair. [1]

Welcome to our naturopathic approach to parasite prevention and treatment. We believe parasites are not just physical invaders, but also disruptors of the delicate balance of the microbiome, compromising immunity and contributing to chronic inflammation. Understanding their life cycles and how they interact with the human body is crucial in preventing and treating these pesky invaders. Let us guide you through a holistic approach that addresses both the symptoms and root causes of parasitic infections, helping you achieve optimal health and well-being.

How Common Are Intestinal Parasites?

Contrary to popular belief, parasitic infections are widely spread, and developed countries are no exception. In the U.S. alone, millions of people are infected with parasites each year, often without knowing it. According to the CDC, some of the most common parasitic infections in the U.S. include toxoplasmosis, giardiasis, and cryptosporidiosis [1].

People at higher risk include:

• International travelers
• Pet owners (especially those with dogs or cats)
• Children in daycare settings
• Individuals with weakened immune systems
• People who consume raw or undercooked meat or fish

Naturopathic practitioners often have patients with vague, chronic symptoms such as fatigue, bloating, and skin issues that may be linked to undiagnosed parasitic infections. These cases are frequently overlooked in conventional medicine, which makes awareness and testing crucial.

Parasites in the Gut: What to Look out For

Symptoms of parasitic infections can vary from very subtle to severe and life-threatening, depending on the type of parasite and the individual’s immune response.

Common symptoms include:

• Chronic digestive issues: bloating, gas, diarrhea, constipation, or abdominal pain
• Unexplained fatigue or brain fog
• Skin rashes, itching, or hives
• Nutrient deficiencies (especially iron and B12)
• Unexplained weight loss or sudden increase in appetite
• Sleep disturbances or teeth grinding (especially in children)
• Mood changes, including anxiety or irritability

From a naturopathic lens, these symptoms may be part of a broader picture of gut dysbiosis or immune dysregulation. Parasites can also contribute to systemic inflammation, which may exacerbate autoimmune conditions or hormonal imbalances.

The Holistic Approach to Preventing Parasitic Infections

Prevention is always better than a cure when it comes to your health, and this is especially true with parasites. While hygiene and sanitation are critical, a naturopathic approach puts the emphasis on strengthening the body’s natural defenses.

Practical Prevention Tips:

• Wash your hands thoroughly, especially after using the bathroom or handling pets
• Drink filtered or purified water, especially when traveling
• Avoid raw or undercooked meat, fish, and shellfish
• Wash fruits and vegetables thoroughly
• Wear shoes outdoors to avoid soil-transmitted helminths (worms)
• Practice safe food storage and preparation

Naturopathic Prevention Aids:

• Support gut health with probiotics and fermented foods
• Use antimicrobial herbs like garlic, oregano, and ginger in cooking
• Maintain a strong immune system by getting enough sleep, managing stress, and eating nutrient-rich foods

Travelers should be especially cautious in areas with poor sanitation. Using bottled water, avoiding uncooked street food, and taking natural antimicrobial supplements (under supervision) can help reduce risk.

When to be Concerned About Intestinal Parasites

You should consider getting tested for a parasitic infection if you experience persistent or unexplained symptoms, especially after travel, exposure to untreated water, or contact with animals.

Red flags to be aware of include:

• Ongoing digestive issues that don’t respond to dietary changes
• Skin eruptions or itching with no clear cause
• Sudden food sensitivities or allergies
• Chronic fatigue or brain fog
• Iron-deficiency anemia without a known source

In naturopathic practice, we often see patients who have been told by their physicians that “everything looks normal” on standard labs, yet they continue to feel unwell. In such cases, a deeper investigation into parasites and gut health may be needed.

When to Test for Intestinal Parasites

Testing is essential for accurate diagnosis and effective treatment. You should consider testing for parasitic infection if:

• You’ve traveled to a high-risk area
• You have persistent GI symptoms
• You’ve been exposed to contaminated water or food
• You have pets or work with animals
• You’ve tried other treatments without success

Common Tests Include:

• Comprehensive stool analysis ("CSA+P" - often over 3 day period)
• Blood tests for specific parasites or antibodies
• Saliva or urine tests (less common but used in some integrative practices)

Naturopathic doctors may also use functional lab testing to assess gut flora, inflammation, and immune markers, providing a more complete picture of your internal ecosystem.

Are Parasite Cleanses Just a Hype?

Parasite cleanses are trending on TikTok and Instagram, often promoted as miracle cures for bloating, fatigue, and even acne. But are they legit, and do the benefits outweigh the risks?

The Reality of Parasite Cleanses

Most over-the-counter “cleanses” are not backed by science. They often include a mix of herbs like wormwood, black walnut, and clove, which do have traditional uses but may not be effective or safe, without proper guidance [2]. 

Potential Risks of DIY Cleanses:

• Can cause diarrhea, dehydration, or nutrient loss
• May interact with medications
• Could mask or worsen underlying conditions

From a naturopathic standpoint, cleansing can be beneficial. However, it’s important that it’s done in conjunction with proper testing, under supervision, and with professional support and part of an integrated treatment plan. A personalized protocol that includes gut healing, immune support, and dietary changes is far more effective than a one-size-fits-all cleanse.

The bottom line: be skeptical and ask good questions of these vendors. Herbs are not FDA approved and it takes an herbalist or a similar experienced practitioner to dose them properly. Social media is an easy way for people to manipulate facts and make a buck. There's no guarantee that a cleanse will work - or even work for your particular situation. The "parasites in the toilet bowl" photos you see on social media could be from 1 in a 1,000 people who tried it. Be wary and ask an expert. 

Parasite Treatments: Traditional vs Naturopathic

Traditional Medical Treatments:

• Prescription antiparasitics (e.g., albendazole, ivermectin, metronidazole)
• Antibiotics for secondary infections
• Follow-up testing to confirm eradication

These treatments are often effective and necessary, especially for acute or severe infections.

Naturopathic Treatments:

• Herbal antimicrobials: wormwood, black walnut, berberine, neem
• Gut support: probiotics, glutamine, digestive enzymes
• Anti-inflammatory diet: low sugar, high fiber, anti-parasitic foods (pumpkin seeds, garlic)
• Detox support: liver and lymphatic drainage, hydration, binders like activated charcoal

The fact is, in the U.S., we have perfectly good, inexpensive, highly-studied medications that effectively kill parasites. This may come as a surprise, but as a naturopathic doctor who straddles both the pharmacological and herbal worlds, I can tell you that clinically, this is an area where herbs don't do as well of a job as meds. 

The best patient outcomes are often a combination of both approaches, using targeted pharmaceuticals and supporting the body’s healing process with natural therapies.

Common Myths & Misconceptions about Intestinal Parasites

There are plenty of myths and unsupported ‘facts’ when it comes to parasitic infections, so let’s bust some of them:

Parasite Myth #1 Parasites only affect people in poor countries.

False. Parasites are found worldwide, including in the U.S. and Europe, and all developed countries without exception.

Parasite Myth #2: It’s obvious when you have a parasite.

False. Many infections are asymptomatic or cause very vague symptoms that can be attributed to other causes.

Parasite Myth #3 Natural remedies are always safe.

Not always. Herbs can be a powerful medicine, but they can also be toxic or interact with medications if misused.

Parasite Myth #4: Everyone should do a parasite cleanse from time to time.

Not necessarily. Cleansing without testing can do more harm than good.

The Bottom Line on Intestinal Parasites

Parasites are more common and more complex than most people think. They can cause a wide range of symptoms, from digestive distress to fatigue and skin issues. While social media may oversimplify the issue, a thoughtful, evidence-based approach is essential.

If you suspect a parasitic infection, don’t guess. Work with a qualified healthcare provider—ideally one who understands both conventional and naturopathic medicine. With proper testing, targeted treatment, and holistic support, you can restore balance and reclaim your health.

References:

[1] Cleveland Clinic. (n.d.). Parasites: Types, Symptoms, Treatment & Prevention. Retrieved June 26, 2025, from https://my.clevelandclinic.org/health/diseases/24911-parasites

[2] Cleveland Clinic. (2025, March 7). Parasite Cleanse: Is It Safe? And Side Effects. Retrieved June 26, 2025, from https://health.clevelandclinic.org/parasite-cleanse

[3] Johns Hopkins Medicine. (n.d.). Parasitic Infections of the Skin. Retrieved June 26, 2025, from https://www.hopkinsmedicine.org/health/conditions-and-diseases/parasitic-infections-of-the-skin