Giardiasis
When To Call a Doctor
If you suspect giardiasis, call your doctor immediately if:
- Diarrhea is black or bloody. Note: Medicines containing bismuth (such as Pepto-Bismol) can turn stools black, but this is not harmful.
- Signs of severe dehydration appear. These include:
- Little or no urine (or wet diapers) for 8 hours, or fewer than 3 urinations (or wet diapers) in 24 hours, usually with one or more of the other signs of dehydration listed below.
- Doughy skin that doesn't bounce back when pinched.
- Difficult or slow response or confusion.
- Sunken eyes.
- Sunken soft spot (fontanel) on an infant's head.
- Low blood pressure.
- Dizziness, especially if you feel dizzy when you stand up or change position suddenly.
Call within a day if you have:
- Belly pain along with diarrhea, and the pain is not relieved by passing stools or gas.
- Diarrhea along with a fever of 101°F (38°C) or higher with chills, vomiting, or fainting (not just lightheadedness).
- Severe diarrhea (many watery stools in a person who also seems very sick) that lasts longer than:
- 2 days in an adult.
- 1 to 2 days in a child younger than 4.
- 8 hours in an infant 3 to 6 months old.
- 4 hours in an infant younger than 3 months.
Call a doctor if:
- Diarrhea develops and persists after you have swallowed untreated water.
- Mild to moderate diarrhea (a few stools that are looser than normal without other signs of illness) lasts longer than 4 to 7 days in a child.
- Diarrhea continues without obvious cause for more than 1 to 2 weeks.
- An infant or child is not developing or gaining weight as expected (failure to thrive).
Watchful Waiting
Most cases of diarrhea are caused by a viral infection and improve with a few days of home care. But if diarrhea is severe or lasts longer than a week or so, or if the above symptoms are present, call your doctor for advice.
Who To See
The following health professionals will be able to diagnose and treat giardiasis:
Referral to a gastroenterologist usually is not necessary unless symptoms are persistent or severe.
To prepare for your appointment, see the topic Making the Most of Your Appointment.
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| Author: | Maria G. Essig, MS, ELS | Last Updated: October 16, 2007 |
| Medical Review: | E. Gregory Thompson, MD - Internal Medicine W. David Colby IV, MSc, MD, FRCPC - Infectious Disease | |
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