Examples
| Generic Name | Brand Name |
|---|
| metronidazole | Flagyl, Noritate, Protostat |
| tinidazole | Tindamax |
How It Works
These medicines kill Giardia lamblia in the
digestive tract.
Metronidazole comes in tablet and liquid forms. It usually is taken
in tablet form for 3 to 7 days for treatment of
giardiasis.
Tinidazole comes
in tablet form. It usually is taken for 1 day either in one dose or in several
doses throughout the day.
Why It Is Used
These medicines are used to treat certain bacterial and parasite
infections. They also are an effective treatment for giardiasis
infection.
These medicines may be used if stool analysis or other testing
indicates giardiasis infection.
If your doctor thinks that your symptoms are caused by giardia, he
or she may prescribe one of these medicines even before your test results are
back.
If you are pregnant, talk with your doctor or pharmacist before
taking these medicines.
How Well It Works
Metronidazole cures giardiasis in adults 80% to 95% of the
time.1
Tinidazole is very effective for the treatment of giardiasis—a
single dose often cures the infection with very few side effects.2
Side Effects
The most common side effects of these medicines include:
- A metallic taste in the
mouth.
- Nausea,
vomiting.
- Dizziness.
- Headache.
A rare side effect is a low number of
white blood cells (neutropenia, leukopenia). The white
blood cell count returns to normal when you stop taking the drug.
Do not drink alcohol while you are taking
metronidazole or tinidazole. Using alcohol while you are taking these
medicines can cause headaches, nausea, reddening of the face, belly cramps, and
vomiting. You should also avoid alcohol for at least 3 days after you finish
your last dose of these medicines.
See Drug Reference for a full list of side effects. (Drug Reference
is not available in all systems.)
What To Think About
Metronidazole may be used with caution in pregnant women.
Tinidazole has only recently been
approved by the U.S. Food and Drug Administration (FDA) for the treatment of
giardiasis, although it has been available in other parts of the world.
Do not use alcohol while you are taking either of these medicines
or for 3 days after you finish your last dose.
Complete the
new medication information form (PDF)
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to help you understand this medication.