Parasites can live within the intestines for years without causing any 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

The following factors put you at higher 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
• Immune-compromised
• HIV or AIDS

Your health care provider will ask if you have traveled overseas recently and whether you have recently lost weight. If your health care provider 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 antidiarrhea drugs or antibiotics are given, or x-rays with barium are taken. Three (five for pinworm) stool samples are needed to find the parasite.
• The string test is used occasionally. For this test, you swallow a string that is then pulled back up. Then samples of your stomach contents on the string are tested.
• The "Scotch tape" test identifies pinworm by touching tape to the anus several times, then examining the tape under a microscope for eggs.
• Your health care provider may use x-rays with barium to diagnose more serious problems caused by parasites, although this test is usually not required.

Drug Therapies

Your health care provider will choose the drug that has the most effect against your intestinal parasite. Drug treatment may occur in one dose or over a period of weeks. Be careful to take the medicine exactly as it is prescribed, or it may not work.

Some examples of drug therapy include:

• Mebendazole (Vermox) -- roundworm, hookworm, pinworm
• Thiabendazole (Mintezol) -- threadworm, pork worm
• Metronidazole (Flagyl) -- giardiasis
• Nitazoxanide (Alinia) -- giardiasis, cryptosporidiosis

Complementary and Alternative Therapies

Generally, conventional medical treatments can eliminate parasites more quickly and with fewer side effects than most alternative treatments. Alternative treatments may be helpful as supportive therapies. However, your health care provider must find out what kind of organism is causing your problems before you start treatment. The following nutritional guidelines will help keep organisms from growing. It is important to maintain good bowel habits during treatment.

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 antiworm properties. 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 promote good bowel elimination.
• Consume more fiber, which helps get rid of worms.
• Supplement your diet with probiotics, such as Lactobacillus acidophilus, Lactobacilus plantarum, Saccharomyces boulardii (250 mg, one to two times per day between meals), and bifidobacteria, to keep parasites from spreading.
• Digestive enzymes will help restore your intestinal tract to its normal state, which makes it inhospitable to parasites. Papain taken 30 minutes before or after meals helps kill worms.
• Vitamin C (250 - 500 mg two times a day) or, if well-tolerated, much higher doses of up to 6,000 mg per day in otherwise healthy adults and zinc (20 - 30 mg per day) support the immune system. Lower vitamin C dose if diarrhea develops.

Herbs

As with any therapy, it is important to work with your health care provider on getting your problem diagnosed before you start any treatment. You may use herbs as dried extracts (capsules, powders, 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. 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 health care provider might consider include:

• Garlic (Allium sativum)
• Barberry (Berberis vulgaris)
• Goldenseal (Hydrastis canadensis)
• Oregon grape (Berberis aquifolium)
• Tea tree oil (Melaleuca alternifolia)
• 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 -- 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

Acupuncture

Can help general bowel health and increase immune function.

Massage

May help stimulate bowel function and elimination.

Your health care provider will retest your stool to be sure your parasite is gone, and will give you advice to help you avoid reinfection. 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 occur 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 health care provider will tell you which drugs are safe to take during pregnancy. Treatment for intestinal parasites during pregnancy should be closely monitored by a qualified practitioner.

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