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How do you know if you have a parasites?

Parasites are organisms that live on or in a host organism and get their food from or at the expense of the host. There are many different types of parasites, ranging from tiny single-celled organisms to larger multi-celled worms. Parasites are a common problem and it is estimated that at least half of the world’s population has some type of parasitic infection. The good news is that there are things you can do to determine if you have parasites and steps you can take to get rid of them.

Signs and Symptoms of Parasitic Infection

Some of the most common signs and symptoms that may indicate the presence of parasites include:

Digestive issues

Parasites living in the digestive tract can cause a variety of gastrointestinal symptoms including:

– Diarrhea or constipation
– Nausea and vomiting
– Bloating and gas
– Cramping and abdominal pain
– Loss of appetite
– Unexplained weight loss

Fatigue and weakness

Parasites can drain the body of vital nutrients, vitamins, and minerals leading to chronic fatigue. Even mild infections can cause you to feel tired, rundown, and weak.

Itching around the anus or vagina

Parasites like pinworms lay eggs around the anus which can cause intense itching and irritation in that area. Some female genital infections can also cause vaginal itching.

Cough and respiratory issues

Parasites like roundworms and hookworms can migrate and get lodged in the lungs, leading to coughing, wheezing, and shortness of breath.

Skin irritation

Certain parasites like scabies burrow into the skin and cause red, itchy rashes. Larva migrans, or creeping eruptions, appear as snakelike, zig-zagging raised lesions on the skin.

Joint and muscle aches

Some parasites release toxins that cause inflammation and joint pain. Others can infiltrate muscles leading to tenderness and soreness.

Grinding teeth at night

Parasites in the intestines can travel up to the mouth and stimulate the gums, causing teeth grinding at night.

Restlessness and trouble sleeping

Discomfort from symptoms like itching and aches can make it hard to get good sleep. Some parasites are also active at night and cause symptoms that disrupt sleep.

Eye pain, light sensitivity, or blurred vision

Ocular toxoplasmosis is a parasitic infection of the retina caused by Toxoplasma gondii which can lead to eye inflammation and vision problems.

Diagnostic Tests for Parasites

If you suspect you may have parasites, there are a number of tests that can be used to try to confirm the diagnosis:

Stool test

Examining a stool sample under a microscope can reveal the presence of certain parasites and eggs. Samples are typically tested 3 times since parasites can be intermittent.

Blood test

A blood test can find antibodies your body produces when fighting a parasitic infection. This works well for parasites like toxoplasmosis.


In some cases, a small tissue sample may be taken from an infected area like the skin, eyes, or intestines to identify parasitic infections.

Imaging tests

Scans like endoscopy, colonoscopy, or CT scan can visually identify parasites in organs like the intestines, lungs, and liver. Ultrasound can also detect parasites like cysts in organs.

Tape test

Putting clear tape on the anal area to collect pinworm eggs which can then be examined under a microscope.

Common Parasites in Humans

There are many different parasites that can infect humans both externally and internally. Some of the most common include:


Pinworms are tiny worms that infect the intestines and colon. The female lays eggs around the anus which causes itching. They are the most common parasite, especially in children.


Roundworms are long, tubular worms that also inhabit the intestines where they can grow over 12 inches long. They are transmitted through contaminated food or soil.


Tapeworms attach to the intestinal walls and can grow very large, up to 30 feet long. They have segmented bodies and can sometimes be seen crawling out the anus.


These single-celled protozoa infect the small intestine causing diarrhea. They are found in contaminated food and water supplies.


Toxoplasma gondii is a single-celled parasite that spreads through cat feces. It causes the disease toxoplasmosis which can affect the eyes and brain.


Related to giardia, cryptosporidium enters the body through contaminated water and damages the bowels, causing severe watery diarrhea.

Scabies mites

Microscopic scabies mites burrow into the skin and lay eggs causing intense itching and rashes. They spread through skin-to-skin contact.


Lice are wingless insects that live on the skin and hair, feeding on blood. The different types include head lice, body lice, and pubic lice (crabs).

Bed bugs

Bed bugs are small parasitic insects that hide during the day and come out at night to feed on human blood, causing red itchy bite marks.


Hookworms attach themselves to the intestinal wall and feed on your blood and tissues. They can cause anemia from blood loss.


Protozoa like Entamoeba histolytica infect the digestive tract and multiply, causing tissue damage and dysentery.

Trichinella spiralis

These parasitic roundworms infect muscle tissue and can travel to the brain and eyes. They are found in undercooked meat like pork.


Schistosoma worms infect the urinary tract and intestines through contact with contaminated water. They can damage organs like the liver.

Who is at Risk for Parasitic Infections?

Certain groups have an increased risk for acquiring parasites:

Young children – Their hygiene habits make transmission more likely

International travelers – Exposure in developing countries with poorer sanitation

Pet owners – Pets like dogs and cats can transmit parasites

Immunocompromised – Those with weakened immune systems are more susceptible

Agriculture workers – More contact with contaminated soil

Institutionalized populations – Like nursing homes where infections spread more easily

Poor sanitation – Areas with limited access to clean water and sewage treatment

Eating raw or undercooked meat/seafood – May contain parasites like tapeworms

Walking barefoot – Soil-transmitted helminths enter through the skin

Can a Parasite Infection Go Away on Its Own?

Some mild parasitic infections may go away on their own as the parasites complete their life cycle and your body’s immune system fights them off. However, most of the time treatment is required to fully eliminate parasitic infections for a few reasons:

– Parasites can multiply quickly and increase in numbers if left untreated.

– They can migrate to other areas of the body and spread widely.

– Parasites can cause significant damage even if you have only mild symptoms.

– Dormant parasite stages may lurk in tissues and reactivate later to cause recurrent infections.

– You can transmit parasites to others if you remain infected.

So although parasites may temporarily die off, the infection often recurs unless medications are taken to completely eliminate all the parasites. Trying to self-treat with home remedies is also not advisable. Seeking medical treatment provides the best chance of ridding your body of parasites for good.

Treatment for Parasitic Infections

Treatment depends on the type of parasite but may involve:

Antiparasitic medications

Prescription drugs like ivermectin, praziquantel, nitazoxanide, metronidazole etc. are used to kill different parasites. Combination therapy is common.

Repeat dosing over days or weeks

Medications are taken for extended courses to interrupt parasite life cycles and ensure they are fully eliminated.

Treating symptoms

Additional medications may be used to manage symptoms like antihistamines for itching, antidiarrheals for diarrhea, and pain relievers.

Fixing complications

If parasites have spread to other tissues or caused secondary issues like malnutrition, anemia, or organ damage, additional interventions may be required.

Deworming family members

Since parasites spread easily to close contacts, family members may also need testing and treatment.

Hygiene and sanitation

Improving hygiene and sanitary practices is important to avoid reinfection. Steps include washing hands, proper food preparation, cleaning with disinfectants etc.

With appropriate treatment, most parasitic infections can be cured. However, certain parasites may require longer treatment or have higher recurrence rates. Seeking prompt medical care provides the greatest chance of eradicating parasites before they can multiply, spread or cause harm.

Prevention of Parasitic Infections

You can take steps to avoid becoming infected with parasites:

– Wash hands thoroughly with soap and water frequently
– Drink purified or bottled water when traveling
– Rinse off fruits and vegetables
– Cook meat thoroughly and avoid raw/undercooked meat or fish
– Avoid swallowing water when swimming in lakes or pools
– Keep sandboxes covered when not in use
– Wear shoes or sandals when outdoors
– Clean pet litter boxes daily
– Use insect repellent and mosquito nets if sleeping outdoors
– Practice safe sex and avoid fecal-oral contact
– Steam, wash, or freeze produce grown in questionable conditions
– Deworm pets regularly and clean up their feces
– Stay updated on vaccinations when traveling

Practicing good hygiene and avoiding sources of contamination can go a long way in preventing parasitic infections. However, parasites can still occasionally be acquired even with the best precautions. Paying attention to signs and symptoms and getting prompt treatment when parasitic infection is suspected leads to the best outcomes.


Parasitic infections are an exceedingly common problem that can sometimes fly under the radar. Being aware of the signs and symptoms, like gastrointestinal issues, rashes, fatigue, and respiratory issues allows you to identify the possible presence of parasites. Diagnostic tests like microscopic analysis of stool samples can help confirm the diagnosis. Numerous parasites may infect humans both internally and externally, acquired through contaminated food and water, insect bites, poor hygiene, travel, pets, and other means. Certain groups have increased risk, but prompt diagnosis and treatment with antiparasitic medications can eliminate the infection fully before parasites multiply and cause harm. While parasites may temporarily resolve on their own, treatment is usually required for a complete cure and prevention of transmission. Practicing good hygiene and sanitation provides the best protection against acquiring parasites in the first place.