Stomach parasites, also referred to as intestinal parasites, are preventable infections that can occur in anyone, although factors such as anal sex, consumption of unfiltered water and poor personal hygiene can increase the risk of infection. Parasitic infections are diagnosed by a doctor after examination of the stool and blood and evaluation of the patient's symptoms. Consider this information derived from the Centers for Disease Control and the Cleveland Clinic about the symptoms of stomach parasites.
People with stomach parasites may have stools that look and smell abnormal. Stomach parasites such as amebiasis and giardiasis may cause the stools to be bloody or greasy. Parasitic infections may also result in stools with particularly foul or strong odors.
Infections caused by stomach parasites may result in changes in bowel movements. People with amebiasis or giardiasis may develop diarrhea, while people infected with pinworms, tapeworms or Ascaris worms may have constipation alternating with diarrhea. People with stomach parasites may also experience pain and cramping during bowel movements.
People with stomach parasites may experience an increase in gas, including both flatulence and belching. Flatulence caused by stomach parasites may be difficult to control and cause embarrassment. The gas may also be accompanied by a strong foul odor and stomach discomfort.
Stomach parasites may cause people to develop nausea and loss of appetite during the course of infection. People with stomach parasites may also have vomiting, which can lead to dehydration. Weight loss and malnutrition may result if nausea persists for a long period of time or is severe.
People with parasitic stomach infections such as amebiasis may develop problems in other parts of the body. Parasites may cause scarring of the liver when they travel through the body to complete stages of the life cycle. People with stomach parasites may also develop damage to the brain, lungs and skin.
Stomach parasites may cause abdominal pain, especially if the number or size of the parasites is large. People who are heavily infested with roundworms may have moderate to severe stomach and abdominal aches and cramps. The abdominal skin of people with stomach parasites may be tender to the touch, and women with parasitic infections may experience vaginal irritations and pain.