Flukes, Tapeworms, and Biliary Parasites

They say, “The best gifts come in small packages,” but I’m afraid you can’t say the same for the tiny and microscopic intestinal and biliary parasites that may be living inside you. Just the thought of having the wriggling, feeding, slimy creatures in your body may be enough to make your hair stand on end. It’s bad enough that its mere mention gives us the skeevies but the creatures themselves do so much more harm than that. These organisms live on or in a host (can be animals or humans) and get food by hijacking their host, robbing it of nutrients, and leaving behind toxic waste.

Parasitic infections used to be confined to tropical and underdeveloped countries. However, because of the ease of travel and migration, developed countries are no longer excluded. Some of the most popular culprits are roundworms (affecting 25% of the world population), hookworms, flatworms, tapeworms, and pinworms, among others. These parasites may populate in various body organs, endangering the different body systems. Since parasites are often acquired by ingesting contaminated food and water, the gastrointestinal system, the hepatic system, and the biliary system are the most common proliferation sites. There has been much written on intestinal parasites, but much less on the biliary organs (the liver, gallbladder, and bile ducts), which will be the focus of this article.

The Biliary Parasites

There are more than 100 types of parasites that can reside in human hosts. Among these, only two types, called nematodes and trematodes can directly affect the gallbladder as well as the liver and the gastrointestinal tract at the same time. Clonorchis sinensis, Opisthorchis viverrini, Opisthorchis felineus Fasciola hepatica and Fasciola gigantica (C. sinensis, O. viverrini, O. felineus , F. hepatica and F. gigantica) are leaf-like, flat flukes that like to inhabit the bile ducts and the gallbladder. The human ascarides, Ascaris lumbricoides, actually dwells in the intestines but can also migrate into the gallbladder through the bile ducts and cause bile duct obstruction.

a. Liver Flukes – Clonorchiasis & Opisthorchiasis (C. sinensis, O. viverrini, O. felineus)
  • These trematodes measure only 10-25 mm long and 3-5mm wide. They may be small but they have the potential to do much damage to their human host. They are commonly known as liver flukes.
  • These parasites feed on the bile or the blood of the host.
  • There are about 13.5 million infected people worldwide. Not all cases are diagnosed because these flukes can be asymptomatic, meaning, they live 25-30 years (or up to 50 years) within your liver, bile ducts or pancreatic ducts and you may never know it.
  • They are often acquired through ingesting fresh watercress, freshwater fish that is raw, pickled, smoked, or dried.
b. Sheep Liver Flukes – Fascioliasis(F. hepatica and F.gigantica)
  • Commonly known as sheep liver flukes as these are parasites often affecting herbivorous animals. Although cases in humans are rare, they can still be acquired through contaminated freshwater plants or when they are eaten by snails or fish that are, in turn, eaten by humans.
  • The adult F. hepatica and F.gigantica live and lay eggs in the bile ducts. They can measure up to 20-40mm in length. They can also invade the intestine.
c. Roundworm – Ascariasis lumbricoides
  • These nematodes transmitted through human feces are often found in the intestine but can migrate to bile ducts and gallbladder.
  • They are commonly called Ascaris, and they affect about 25% of the world’s population.

What are the symptoms of a parasitic infection in the gallbladder?

Although the prevalence of parasitic infections in humans is very high, many cases are left undiagnosed and untreated. It is possible that the presence of liver flukes, sheep liver flukes, and Ascaris may not be bothersome at all. Although these biliary parasites are silently and consistently feeding on bile and blood, there is a huge probability that it would not trigger any symptoms. In fact, they can live for as long as 50 years inside the human body and remain asymptomatic.

For the unfortunate population who experiences the negative effects of these flukes and roundworms, the symptoms exhibited may be very vague and general. Common manifestations such as fever, diarrhea, bloating, loss of appetite, vomiting, and listlessness can be interpreted as a plethora of diseases. In fact, most of these may be familiar to gallbladder patients as some of them are common to both chronic gallbladder symptoms as well as acute gallbladder attacks.

Other symptoms specific to these flukes and Ascaris affecting the GI tract, liver, and gallbladder are abdominal discomfort, dyspepsia, bile stasis (reduced flow of bile from the liver to other parts of the body), reduced movement of the intestines, obstruction of the bile ducts, inflammation of the organs involved and bacterial infections. Those suffering from Ascariasis lumbricoides may have an enlarged liver and gallbladder. This causes tenderness or sharp pain of the right upper quadrant of the body.

What are the complications of having a biliary parasite?

Although the liver fluke, sheep liver fluke, and Ascaris trigger very similar symptoms in the acute phase, complications vary when they reach the chronic phase. Severe infestations may cause the following:

a. Liver Flukes – Clonorchiasis & Opisthorchiasis (C. sinensis, O. viverrini, O. felineus)
  • Intrahepatic and extrahepatic biliary obstruction – blockage of the bile ducts causing the development of biliary sludge and abnormal bile circulation
  • Cholelithiasis – development of gallstones
  • Gallbladder perforation
  • Repetitive cholangitis – a bacterial infection of the bile ducts and gallbladder; treatable with antibiotics but unless the cause of blockage (parasites) is addressed, the infection will just recur.
  • Cholangiohepatitis – inflammation of the liver and bile ducts
  • Worm migration to the liver can lead to damage to the organ or liver cirrhosis
  • Pancreatitis
  • Increased chances of developing cholangiocarcinoma – cancer that arises from the cells within the bile ducts; also called bile duct cancer
  • Hepatocellular carcinoma (HCC) – cancer that starts in the liver
b.Sheep Liver Flukes – Fascioliasis (F. hepatica and F.gigantica)
  • Obstructive jaundice
  • Cholangiohepatitis – inflammation of the liver and bile ducts
  • Acute cholecystitis – inflammation of the gallbladder
  • Intrahepatic stones – formation of stones within the liver
  • Cholelithiasis – development of gallstones
  • Pancreatitis
  • Liver abscesses – swelling of the liver due to infection and collection of pus
c. Roundworm –Ascaris (Ascariasis lumbricoides)
  • Obstructive jaundice
  • Cholangiohepatitis – inflammation of the liver and bile ducts
  • Acute to Chronic cholecystitis – inflammation of the gallbladder
  • Pancreatitis
  • Intrahepatic stones – formation of stones within the liver
  • Cholelithiasis – development of gallstones
  • Liver abscesses – swelling of the liver due to infection and collection of pus
  • Cholangiocarcinoma – cancer that arises from the cells within the bile ducts; also called bile duct cancer
  • Mortality

How can biliary parasites be diagnosed?

Many years ago, the presence of parasites was usually just tested via stool exam. Thanks to modern medicine, there are now many ways that Clonorchiasis, Fascioliasis, and Ascariasis can be diagnosed.

a. Conventional Ova and Parasite Stool Test
  • This is the most basic test that comes with many limitations. This can yield a false negative for the presence of parasites depending on the life cycle of the organism, the particular sample at a given time, the dormancy of parasites, and other factors.
b. Functional Medicine Comprehensive Stool Test
  • More sensitive than the conventional test because of the use of PCR technology to amplify the DNA of the parasite, if there is one.
c. Ultrasonography, CT Scan and Magnetic Resonance Imaging (MRI)
  • Useful for the imaging of the flukes, dilation of the biliary tree due to obstructions, and the detection of stones, cancers, abscesses, or cysts. Characteristic sonographic and CT features can be found for Ascaris and clonorchiasis worms in the gallbladder and nearby organs.
d. Endoscopic Retrograde Cholangio-Pancreatography (ERCP)
  • This procedure enables the doctor to examine and see the pancreatic and bile ducts through an endoscope. ERCP does not only help in the diagnosis but also in therapy and treatment. It can be used as an alternative to surgical procedures.
e. Enzyme-linked Immunosorbent Assay (ELISA) Test
  • This technique detects whether an antibody or antigen against the parasite is present in the sample.

What is the treatment for flukes, tapeworms, and other biliary parasites?

a. Medication (Conservative Treatment)
  • Bithionol and Triclabendazole for sheep liver flukes
  • Praziquantel for liver flukes
  • Albendazole or Mebendazole for ascaris
b. Natural Supplements
  • Parasite cleansing formula (Paratosin covers biliary and intestinal parasites)
  • Bowel cleaner such as Medi-Clay-FX bentonite clay
  • Bile movers such as turmeric and beetroot

Note that both medications and herbal formulas can be hard on the body and it is normal to feel tired and flu-like symptoms from the die-off of the organisms. Plan a parasite detox when you have time to rest.

Parasite Cleanse

Principles – start slowly and work up to full dose. Back down as needed.

  1. Start with something like Paratosin– When detoxifying flukes for the first time, according to the manufacturer, the usual dose of Paratosin for a 150-200lb adult is 12-18 capsules per day for 30 days. Repeat treatments; use 2-4 caps 3x a day for 30 days.
  2. Take something to move the bowel and to cleanse the walls of the intestines simultaneously, such as MediClay-FX. This is a gentle but effective formula.
  3. Stimulate bile flow simultaneously with Gallbladder Formula Elite (or eat The Beet Recipe 3x day).
  4. Take Biliven 2 caps 3x day to help to dilate the bile ducts.
c. Endoscopy
  • Endoscopic sphincterotomy is a less invasive option compared to surgery. Through ERCP, parasites can be extracted, and nobiliary drainage can be done as well. Antihelminthics or drugs that expel parasitic worms are coursed through a tube inserted into the nose and to the GI tract until it reaches the target area.
d. Surgery
  • Last resort for acute and chronic cholecystitis due to parasites or stones. Surgery can be used to extract the parasites.

How can these parasites be avoided?

  • Wash your hands with soap and water several times a day.
  • Proper cooking and food handling – Most flukes, roundworms, and other parasites affecting the intestines, liver, and gallbladder come from contaminated food. It is therefore important that you observe proper food handling and cook your meats and vegetables sufficiently to kill off any parasites that may be in them.
  • Change dietary habits. If you must eat out, avoid rare meats and raw food as much as possible. If you can’t, try to find reputable places known for proper food handling and quality sanitation.
  • Make sure you have clean water. Water filters are very important. Be wary of the manner of your water storage as well. If possible, bring your own water wherever you go. If you need to drink water from elsewhere, make sure that you only take purified water from sealed containers.


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