Gastrointestinal amebiasis is a type of food poisoning caused by a parasite. The infection is rare in developed countries. It is more common in areas with poor sanitation or crowded living conditions.
A parasite named Entamoeba histolytica causes this illness. Your intestine (colon) may become infected when:
Rarely, the parasite gets into the liver or other organs through the blood.
The parasite can live in your gut without causing symptoms. When it causes symptoms, they may include:
The time between the parasite's entry into your body and when you start having symptoms can range from a few days to a few months.
Your healthcare provider will review your symptoms and examine you. You will have tests of your blood and bowel movement.
Sometimes the diagnosis is difficult if you have had the symptoms for a long time. A test called a sigmoidoscopy may be done. This is a procedure in which the healthcare provider puts a thin, flexible, lighted tube into your rectum to look for disease in your colon.
Your healthcare provider will prescribe an antibiotic. Your provider may also prescribe antidiarrheal medicine. Take all medicines exactly as your provider and pharmacist tell you. Take all of the antibiotic medicine prescribed. If you stop taking the antibiotic too soon, your infection may come back.
If your symptoms are severe, you may need intravenous (IV) fluids until the diarrhea gets better. This treatment may be needed to keep you from losing too much fluid and getting dehydrated.
The symptoms of diarrhea usually last 3 to 14 days, but they can last up to 4 weeks.
The symptoms may come back, sometimes because the treatment was not successful and sometimes because you got infected again.
Follow your healthcare provider's instructions.
If you have diarrhea, you may want to let your bowel rest for a few hours by not eating any food. Large amounts of watery diarrhea can cause dehydration, so it’s important to replace the fluids you are losing. Do this by drinking clear liquids, such as water, weak tea, bouillon, apple juice, or sports drinks or other oral rehydrating solutions. You may also drink soft drinks without caffeine (such as 7 UP). Let sodas lose some of their carbonation (go flat) before you drink them. Make sure you drink small amounts often. Not getting enough fluids to replace the fluids your body is losing while you are sick can be very dangerous. This is especially true for children, older adults, and some people who have other medical problems. Suck on ice chips or Popsicles if you feel too nauseated to drink fluids.
It’s OK to keep eating as long as it does not seem to make diarrhea or stomach cramps get worse. Foods that are easiest to digest are soft, plain foods, such as bananas, cooked cereal, rice, plain noodles, gelatin, soft-boiled eggs, toast or bread with jelly, and applesauce. Go back to your normal diet after 2 or 3 days, but avoid milk products and caffeine for a few more days. For several days also avoid fresh fruit (other than bananas), alcohol, greasy or fatty foods, highly seasoned or spicy foods, and most fresh vegetables. Cooked carrots, potatoes, and squash are OK. If eating seems to make the diarrhea worse, go back to just clear liquids for a few hours. Then again try small amounts of the foods that are easy to digest.
If you have cramps or stomach pain, it may help to put a hot water bottle or electric heating pad on your stomach. Cover the hot water bottle with a towel or set the heating pad on low so you don’t burn your skin.
Be cautious about taking antidiarrheal medicines. Nonprescription medicines such as loperamide (sold as Imodium and other trade names) or the prescription medicine Lomotil can make you sicker, especially if the diarrhea is bloody. If you take one of these medicines, make sure you use only the dose recommended on the package. If you have chronic health problems, always check with your healthcare provider before you use any medicine for diarrhea.
Call your healthcare provider if: