Tapeworms: Symptoms, Treatments, and Prevention

Tapeworms are among the oldest known parasites. They vary in size from 6 inches to 26 ft long depending on the type of tapeworm.

Tapeworms are described as flat and ribbon-shaped. They have three parts to their body: head, neck, and body segments called proglottids.

Tapeworms come in more than 1,500 different species. Infections in the United States are mainly caused by three species: the beef tapeworm, the fish tapeworm, and the dwarf tapeworm (the smallest species that will infect humans).

The head has hooks for attaching itself to the intestinal wall. If the head stays attached to the intestinal wall, it can survive and grow into a new tapeworm. The proglottid contains eggs that can break off into the bloodstream and travel throughout the body, causing symptoms.

Tapeworms don’t have intestines; they absorb partially digested materials from their hosts through their skin. Adult tapeworms can live and thrive in the digestive tracts of a variety of hosts, such as humans, dogs, cats, cows, pigs, and fish.

Most tapeworm species have both male and female sexual organs, and reproduce and produce their own offspring.

Tapeworm Life Cycle

Learn more about a parasite infection at this article.

Symptoms Of Tapeworm Infection

Here are common signs and symptoms of a tapeworm infection: 

  • Abdominal Discomfort
  • Diarrhea
  • Malnutrition
  • Muscle Weakness
  • Neurological Damage
  • Weight loss

Common Tapeworms

These are the common types of tapeworms. 

  • Beef tapeworms
  • Beef tapeworms usually range between 10 and 15 feet, but can even grow up to 65 feet long. Cows and humans are the most common hosts for the parasite, but they can only reproduce asexually in humans.
  • Dwarf tapeworms are the smallest kind of tapeworm that affects humans. They are only a few tenths of an inch long. They live in the intestines of humans and rats.
  • Pork tapeworms will usually grow between 1/4 and 1/2 inch long, and live in humans and pigs.
  • Fish tapeworms are the longest tapeworm species, averaging about 30 feet long, but can grow up to 100 feet. They can infect humans, dogs, cats, bears, seals, and weasels.

In North America, the beef tapeworm (taenia saginata) is the most common, but it’s relatively controlled, so it’s doesn’t invade easily. In Latin America, the pork tapeworm (taenia solium) infects millions. The fish tapeworm (diphyllobothrium latum) and pork tapeworm are most common in Asia.

Tapeworms are born from eggs which then develop into adventurous embryos. They leave the host’s digestive system through their bowels and then find the nearest source of water. Baby tapeworms are ingested by both animals and humans regularly.

Tapeworm embryos are ingested by drinking contaminated water or by direct contact with feces. That’s another good reason to always wash your hands after using the toilet.

Tapeworm Overview - Symptoms, Treatment, and Prevention

Tapeworm Assumptions

It’s a common assumption that embryos grow into full-grown tapeworms, but they usually don’t. The undeveloped tapeworms burrow through their host’ s abdominal lining and enter the bloodstream.

Veins and arteries transport the tapeworms from one organ to another.

Once the embryo finds a place where it can develop, it forms a fluid sac (a cyst) around itself. The embryo doesn’t leave the sac until the host’s flesh has been eaten by another animal. Tapeworms usually get into your body through food.

Tapeworm Prevention

There are a number of prevention steps you can take to avoid a tapeworm infection:

  • Avoid undercooked meat and fish
  • Cook meat at temperatures of at least 150 degrees Fahrenheit
  • Freeze fish for 24 hours before cooking
  • Freeze meat for 12 hours before cooking
  • Promptly treat tapeworm in pets or livestock
  • Wash hands before and after handling meat or seafood
  • Wash hands before eating
  • Wash hands after using the toilet

Follow these simple rules and you won’t be one of the millions who deal with intestinal parasites and their unpleasant side effects.

Tapeworm Treatments

Albendazole is commonly used for tapeworms, as well as hookworms, pinworms and roundworms.  

Sometimes, praziquantel (Biltricide) is also used for the treatment of tapeworms.

If you think you may have a tapeworm, it’s best to see your doctor for diagnosis and treatment options.  

  • National Library of Medicine: https://www.ncbi.nlm.nih.gov/books/NBK537154
  • Science: https://www.science.org/content/article/tapeworms-may-be-good-your-brain
  • Michigan State University: https://www.canr.msu.edu/news/tips_to_help_you_avoid_tapeworms
  • Center for Disease Control: https://www.cdc.gov/parasites/taeniasis/index.html

Julie C. Guider MyGoodGut

Medically reviewed by Julie Guider, M.D.

Dr. Julie Guider earned her medical degree from Louisiana State University School of Medicine. She completed residency in internal medicine at the University of Virginia. She completed her general gastroenterology and advanced endoscopy fellowships at University of Texas-Houston. She is a member of several national GI societies including the AGA, ACG, and ASGE as well as state and local medical societies.