Nitazoxanide (Alinia) is an antiprotozoal medication. It's a first-choice treatment option for diarrhea caused by the parasites Giardia lamblia or Cryptosporidium parvum. It comes as a tablet (for people ages 12 years and older) and a strawberry-flavored oral suspension (for children ages 1 year and older). Nitazoxanide (Alinia) is taken by mouth, typically twice daily for 3 days. Side effects of this medication can include headache and a change in urine color.
Diarrhea caused by Giardia lamblia or Cryptosporidium parvum
Nitazoxanide (Alinia) is an antiprotozoal. It works by blocking a specific protein that parasites need to grow and survive.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
Treatment of choice for diarrhea caused by certain parasites
Only needs to be taken twice a day for 3 days
Can be used in young children
Comes as a tablet and flavored oral suspension (liquid)
Needs to be taken with food
Might not work as well in people with weakened immune systems
Unknown if safe in pregnancy or breastfeeding
Take nitazoxanide (Alinia) about every 12 hours. Always take the medication with food. Food helps your body absorb more of the medication. If you take nitazoxanide (Alinia) on an empty stomach, you might not be getting the full dose, and you're more likely to get stomach upset as well.
Make sure to finish the full course of nitazoxanide (Alinia), even if your diarrhea gets better. Most people will take 6 doses over a period of 3 days. If you stop the medication too early, the diarrhea might come back and can become harder to treat.
The nitazoxanide (Alinia) tablet only comes in one strength (500 mg), which is too high for young children. Do not break the tablet in half for a smaller dose. Children under 12 years of age must use the oral suspension.
If you or your child is taking Alinia (nitazoxanide) oral suspension, make sure to shake it well and use the measuring device that comes with the medication to measure out the doses. Don't use kitchen or measuring spoons to measure your dose because they aren't accurate and can cause you to take the wrong dose.
Alinia (nitazoxanide) oral suspension is good for 7 days after it's prepared in the pharmacy. Store it at room temperature. After 7 days (and after you or your child has completed the treatment), throw away any leftover medication.
Nitazoxanide (Alinia) can interact with certain medications, including warfarin (Coumadin). Let your prescriber and pharmacist know beforehand about all the medications you're taking.
The parasite can come out in your stool, even a week after you finish nitazoxanide (Alinia) treatment. There's a risk that it can spread to other people or animals. Remember to wash your hands frequently, especially after you go to the bathroom or after changing your child's diaper.
The nitazoxanide (Alinia) tablet is only for people ages 12 years and older. Children under 12 years old should only take the Alinia (nitazoxanide) 100 mg/5 mL suspension.
Nitazoxanide (Alinia) should be taken with food. The typical length of treatment is 3 days.
Age 12 years or older: The typical dose is 500 mg by mouth every 12 hours.
Age 4 to under 12 years: The typical dose is 200 mg by mouth every 12 hours.
Age 1 to under 4 years: The typical dose is 100 mg by mouth every 12 hours.
Diarrhea caused by Giardia lamblia or Cryptosporidium parvum
Trichomoniasis ("trich")
Giardiasis (parasitic gut infection)
Amebiasis (parasitic gut infection)
Bacterial vaginosis (BV)
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Centers for Disease Control and Prevention. (n.d.). Protect your child: Use the right tool to give the right dose.
Centers for Disease Control and Prevention. (2024). About cryptosporidiosis.
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