The two main types of intestinal parasites are helminths and protozoa. Helminths are worms with many cells. Tapeworms, pinworms, and roundworms are among the most common helminths in the United States. In their adult form, helminths cannot multiply in the human body. Protozoa have only one cell, and can multiply inside the human body, which can allow serious infections to develop. Intestinal parasites are usually transmitted when someone comes in contact with infected feces (for example, through contaminated soil, food, or water). In the U.S., the most common protozoa are giardia and cryptosporidium.

Parasites can live in the intestines for years without causing symptoms. When they do, symptoms include the following:

• Abdominal pain
• Diarrhea
• Nausea or vomiting
• Gas or bloating
• Dysentery (loose stools containing blood and mucus)
• Rash or itching around the rectum or vulva
• Stomach pain or tenderness
• Feeling tired
• Weight loss
• Passing a worm in your stool

These things raise your risk for getting intestinal parasites:

• Living in or visiting an area known to have parasites
• International travel
• Poor sanitation (for both food and water)
• Poor hygiene
• Age. Children and the elderly are more likely to get infected.
• Exposure to child and institutional care centers
• Having a weakened immune system
• HIV or AIDS

Your doctor will ask if you have traveled out of the country recently and whether you have recently lost weight. If your doctor thinks you have an intestinal parasite, you will probably have one or more of the following tests:

• Fecal testing (examination of your stool) can identify both helminths and protozoa. Stool samples must be collected before you take any anti-diarrhea drugs or antibiotics, or before x-rays with barium are taken. Several stool samples may be needed to find the parasite.
• The "Scotch tape" test identifies pinworms by touching tape to the anus several times, then looking at the tape under a microscope for eggs.
• Your doctor may use x-rays with barium to diagnose more serious problems caused by parasites, although this test is usually not required.

Drug Therapies

Your doctor will choose the drug that is most effective against your intestinal parasite. You may need one dose, or you may have to take the medication for several weeks. Be careful to take the medicine exactly as it is prescribed, or it may not work.

Complementary and Alternative Therapies

Conventional medical treatments can get rid parasites more quickly and with fewer side effects than most alternative treatments. Alternative treatments may be helpful along with conventional medications. However, your doctor must find out what kind of organism is causing your problems before you start treatment. The following nutritional guidelines may help keep parasites from growing.

Nutrition and Supplements

• Avoid simple carbohydrates, such as those found in refined foods, fruits, juices, dairy products, and all sugars, except honey.
• Eat more raw garlic, pumpkin seeds, pomegranates, beets, and carrots, all of which have been used traditionally to kill parasites. In one study, researchers found that a mixture of honey and papaya seeds cleared stools of parasites in 23 out of 30 subjects. Drink a lot of water to help flush out your system.
• Eat more fiber, which may help get rid of worms.
• Probiotics (Lactobacillus acidophilus, Lactobacilus plantarum, Saccharomyces boulardii, and bifidobacteria). Help keep your digestive tract healthy. Probiotics may not be appropriate in some severely immune compromised patients. Talk to your doctor.
• Digestive enzymes will help restore your intestinal tract to its normal state, which makes it inhospitable to parasites. Papain is an enzyme from the papaya plant that may help kill worms when taken 30 minutes before or after meals. Papain may increase bleeding in people with clotting disorders, or in those taking blood-thinning medications, such as warfarin (Coumadin) among others.
• Vitamin C. Supports the immune system. Lower the dose if diarrhea develops.
• Zinc. Supports the immune system. Zinc may interact with certain medications, particularly some antibiotics, and it may not be appropriate for people with HIV/AIDS. Talk to your doctor.

Herbs

Herbs are a way to strengthen and tone the body's systems. As with any therapy, you should work with your doctor to diagnose your problem before starting treatment. You may use herbs as dried extracts (capsules, powders, or teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). People with a history of alcoholism should not take tinctures.

Many of the herbs used to treat intestinal parasites have toxic side effects or interfere with other medications. Use them only under the supervision of a qualified practitioner. Your health care provider should treat you with the most gentle herb that is effective for the type of parasite you have. A few of the herbs that your provider might consider include:

• Garlic (Allium sativum)
• Barberry (Berberis vulgaris)
• Goldenseal (Hydrastis canadensis)
• Oregon grape (Berberis aquifolium)
• Anise (Pimpinella anisum)
• Wormwood ((Artemisia annua))
• Curled mint (Mentha crispa)
• Black walnuts (Juglans nigra)

Homeopathy

As with other treatments, your health care provider must first diagnose the kind of parasite you have. Before prescribing a remedy, homeopaths take into account a person's constitutional type, includes your physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors, as well as any current symptoms, when determining the most appropriate remedy for a particular individual. The following remedies may be used:

• Cina
• Cuprum oxidatum nigrum
• Indigo
• Teucrium
• Podophyllum
• Spigelia
• Sabadilla
• Stanum

Your doctor will retest your stool to be sure your parasite is gone, and will give you advice to help you avoid getting infected again. Follow these instructions carefully. Getting a parasite a second time can cause more serious health problems.

The seriousness and length of illness varies with the specific intestinal parasite. Complications happen more often in older people, and in people who already have serious illnesses, such as AIDS.

Intestinal parasites can be more serious if you are pregnant. Your doctor will tell you which drugs are safe to take during pregnancy. Your doctor should closely monitor any treatment for intestinal parasites during pregnancy.

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