There are two main types of intestinal parasites: helminths and protozoa. Helminths are worms with many cells. Usually, helminths cannot multiply in the human body and will eventually clear up without infecting you again. Protozoa have only one cell. They can multiply inside the human body.

Symptoms include the following.

• 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 personal cleanliness
• Age—children are more likely to get infected
• Exposure to child and institutional care centers
• Acquired immunodeficiency syndrome (AIDS)

Your health care provider will ask if you have traveled overseas recently and whether you have recently lost weight. Your provider will examine you. If he or she 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 placing tape around the anus at night.
• Your health care provider may use X rays with barium to diagnose more serious problems caused by parasites, although this is usually not required.

Your health care provider will choose the drug most effective against your intestinal parasite. Drug treatment may be just one dose or several over a period of weeks. Be careful to take the medicine just as it is prescribed or it may not work.

While alternative treatments may be helpful in getting rid of intestinal parasites, 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.

• Avoid simple carbohydrates such as are found in refined foods, fruits, juices, dairy products, and all sugars.
• Eliminate caffeine and alcohol.
• Eat more raw garlic, pumpkin seeds, pomegranates, beets, and carrots, all of which have antiworm properties. Drink a lot of water to promote good bowel elimination.
• 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. Acidophilus supplements help normalize bowel bacteria (one capsule with meals).
• Vitamin C (250 to 500 mg two times a day)and zinc (20 to 30 mg per day) support the immune system.

Herbs are generally a safe way to strengthen and tone the body's systems. As with any therapy, it is important to work with your health care provider on getting your problem diagnosed before you start any treatment. Herbs may be used as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Many of the herbs used to treat intestinal parasites have toxic side effects. Use them only under the supervision of a qualified practitioner. He or she will treat you with the most gentle herb that is effective for the type of parasite you have. A few of the herbs that the herbal specialist might consider include:

• Garlic (Allium sativum) 
• Barberry (Berberis vulgaris) 
• Goldenseal (Hydrastis canadensis)

In a recent study of children with acute diarrhea, those who received an individualized homeopathic treatment for five days had a significantly shorter duration of diarrhea than children who received placebo. Before prescribing a remedy, homeopaths take into account a person's constitutional type. In homeopathic terms, a person's constitution is his or her 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 were used to treat the children mentioned in the previous study:

• Arsenicum album — for foul-smelling diarrhea with a burning sensation in the abdomen and around the anus; this remedy is most appropriate for individuals who feel anxious, restless, and exhausted; symptoms tend to worsen after midnight and in the cold; symptoms improve with warmth; vomiting may also occur 
• Chamomilla — for greenish, frothy stool that smells like rotten eggs; used primarily for children, especially those who are irritable, argumentative, difficult to console, and change their minds frequently 
• Calcarea carbonica — for children who fear being in the dark or alone and who perspire heavily while sleeping; stools have a sour odor
• Podophyllum — for explosive, gushing, painless diarrhea that becomes worse after eating or drinking (even though the individual is often thirsty and craves cold drinks); exhaustion often follows bowel movements and the individual for whom this remedy is appropriate may experience painful cramps in lower extremities
• Sulphur — for irritable and weepy children; may have a red ring around the anus and diarrhea with the odor of rotten eggs

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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