1. Take the Tummy Trouble Quiz
2. Digestive Disease Myths Slideshow Pictures
3. Heartburn? Foods to Eat, Foods to Avoid Slideshow

Medical Author:

Betsy P Schrader, MD

Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Giardiasis can show itself in different ways. Some people can be carriers of the parasite and have no symptoms of the disease, but they pass cysts in their stool and pass the disease to others. Others may develop acute or chronic diarrheal illnesses in which the symptoms occur 1-2 weeks after swallowing the cysts.

• Diarrhea: Up to 90% of people with giardiasis complain of diarrhea. Stool is usually described as profuse and watery early in the disease. Later in the disease, stools become greasy, foul smelling, and often floats. Blood, pus, and mucus are usually not present. Symptoms may last for one to several weeks.
• Weight loss, loss of appetite
• Bloating, abdominal cramping, passing excessive gas, sulfur-tasting burps
• Occasional nausea, vomiting, fever, rash, or constipation

• Diarrhea: Stools are often greasy, foul smelling, yellowish, and may alternate between diarrhea and constipation.
• Abdominal pain worsens with eating
• Occasional headaches
• Weight loss

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