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Albendazole is taken as a tablet.
Metronidazole comes in tablet and liquid forms. It usually is taken in
tablet form for 3 to 7 days for treatment of
Nitazoxanide comes as tablets and as a liquid.
Paromomycin comes as a capsule. It is usually taken several times a day for 5 to 10 days.
in tablet form. It usually is taken for 1 day either in one dose or in several
doses throughout the day.
These medicines kill Giardia lamblia in the digestive tract.
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 shows giardiasis
infection is present.
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.
Albendazole cures giardiasis 62% to 95% of the time.1
Metronidazole and tinidazole cures giardiasis in adults 80% to 95% of
the time.2, 3
Nitazoxanide is successful for treating giardiasis 65% to 85% of the time.2 It is often used to treat giardiasis in children.
Paromomycin cures giardiasis 50% to 70% of the time.4
All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine.
Here are some important things to think about:
Call 911 or other emergency services right away if you have:
Call your doctor right away if you have:
Common side effects of these
Metronidazole and tinidazole
Do not drink alcohol while you are taking metronidazole or tinidazole. Drinking 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.
Long-term use of nitazoxanide can cause the whites of the eyes to turn yellow. But the yellow color goes away after use of this medicine is stopped.
See Drug Reference for a full list of side
effects. (Drug Reference is not available in all systems.)
Medicine is one of the many tools your doctor has to treat a health problem. Taking medicine as your doctor suggests will improve your health and may prevent future problems. If you don't take your medicines properly, you may be putting your health (and perhaps your life) at risk.
There are many reasons why people have trouble taking their medicine. But in most cases, there is something you can do. For suggestions on how to work around common problems, see the topic Taking Medicines as Prescribed.
Do not use this medicine if you are pregnant or planning to get pregnant. If you need to use this medicine, talk to your doctor about how you can prevent pregnancy.
These medicines are not used for pregnant women during the first trimester of pregnancy. If you are pregnant or planning to get pregnant, do not use any medicines unless your doctor tells you to. Some medicines can harm your baby. This includes prescription and over-the-counter medicines, vitamins, herbs, and supplements. And make sure that all your doctors know that you are pregnant or planning to get pregnant.
If you are pregnant, breast-feeding, or planning to get pregnant, do not use any medicines unless your doctor tells you to. Some medicines can harm your baby. This includes prescription and over-the-counter medicines, vitamins, herbs, and supplements. And make sure that all your doctors know that you are pregnant, breast-feeding, or planning to get pregnant.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.
Complete the new medication information form (PDF)new medication information form (PDF)(What is a PDF document?) to help you understand this medication.
Hoque ME (2013). Giardiasis. In ET Bope, RD Kellerman, eds., Conn's Current Therapy 2013, pp. 100–103. Philadelphia: Saunders.
Hill DR, Nash TE (2010). Giardia lamblia. In GL Mandell et al., eds., Mandell, Douglas, and Bennett's Principles and Practice of Infectious Disease, 7th ed., vol. 2, pp. 3527–3534.
Philadelphia: Churchill Livingstone Elsevier.
Rosenthal PJ (2010). Protozoal
and helminthic infections. In SJ McPhee, MA Papadakis, eds., 2010 Current Medical Diagnosis and Treatment, 49th ed., pp. 1348–1389. New York:
American Academy of Pediatrics (2009). Giardia intestinalis infections (giardiasis). In LK Pickering et al., eds., Red Book: 2009 Report of the Committee on Infectious Diseases, 28th ed., pp. 303–305. Elk Grove Village, IL: American Academy
August 8, 2013
E. Gregory Thompson, MD - Internal Medicine & W. David Colby IV, MSc, MD, FRCPC - Infectious Disease
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