Nitazoxanide 500 mg is a broad-spectrum antiparasitic and antiviral medication widely used for treating intestinal infections, especially diarrhea caused by Giardia lamblia and Cryptosporidium parvum. It has also shown effectiveness against some viruses and helminths, making it a valuable tool in managing gastrointestinal infections. Understanding the appropriate dosage of Nitazoxanide for adults and children is essential to ensure effective treatment while minimizing side effects.
This guide offers an in-depth look at how Nitazoxanide is prescribed, its formulation, and how dosage differs based on age, weight, and the condition being treated.
What Is Nitazoxanide?
Nitazoxanide 200 mg is an oral medication that interferes with the energy metabolism of parasites and anaerobic organisms. It is commonly used to treat:
-
Giardiasis
-
Cryptosporidiosis
-
Rotavirus and Norovirus-related diarrhea
-
Amebiasis
-
Helminthic infections
It is available in two main forms:
-
Tablets (500 mg) for adults and older children
-
Oral suspension (100 mg/5 mL) for younger children
Once ingested, Nitazoxanide is quickly metabolized into its active form, tizoxanide, which works to disrupt the reproduction and survival of parasites in the gastrointestinal tract.
Why Dosage Matters
The correct dosage of Nitazoxanide depends on several factors:
-
Age
-
Body weight
-
Severity and type of infection
-
Formulation used (tablet or suspension)
Incorrect dosing may lead to treatment failure, resistance development, or side effects, particularly in young children or immunocompromised individuals.
Recommended Dosage for Adults
✅ Standard Adult Dose:
-
500 mg of Nitazoxanide every 12 hours (i.e., twice a day) for 3 days
-
Total daily dose: 1000 mg
This is the standard recommendation for treating infections like:
-
Giardiasis
-
Cryptosporidiosis
-
Other protozoal diarrhea in adults and adolescents (aged ≥12 years)
The medication should be taken with food to enhance absorption and reduce the risk of stomach upset.
Recommended Dosage for Children
✅ Children Aged 1–3 Years:
-
5 mL (100 mg) of the oral suspension every 12 hours
-
Duration: 3 days
-
Total daily dose: 200 mg
✅ Children Aged 4–11 Years:
-
10 mL (200 mg) of the oral suspension every 12 hours
-
Duration: 3 days
-
Total daily dose: 400 mg
✅ Children Aged 12 and Older:
-
Follow adult dosage: 500 mg tablet every 12 hours for 3 days
Note: Dosage adjustments are rarely needed unless a child has renal or hepatic impairment, in which case a pediatrician’s guidance is crucial.
Weight-Based Dosing
In some settings—particularly in children under 12 with atypical body weights—Nitazoxanide dosing may be determined by weight rather than age. A general recommendation is:
-
7.5 mg/kg every 12 hours, with a maximum of 500 mg per dose
For example:
-
A child weighing 15 kg may receive about 112.5 mg per dose, rounded to 100 mg, which matches the 5 mL dose of the oral suspension.
Special Considerations
1. Renal or Liver Impairment
There is limited data on the use of Nitazoxanide in people with kidney or liver disease. Use caution, and consult a healthcare provider for adjusted dosing or alternatives.
2. Immunocompromised Patients
In HIV-positive individuals or immunocompromised children, longer treatment durations may be required. For example, up to 14 days of therapy may be prescribed for cryptosporidiosis.
3. Off-Label Uses
Nitazoxanide is also studied for viral infections such as influenza and COVID-19. In such cases, dosing and duration may vary based on ongoing clinical trials or physician guidance.
How to Take Nitazoxanide
Tablets:
-
Swallow whole with water
-
Take with food to reduce stomach upset
-
Do not crush or chew
Oral Suspension:
-
Shake well before each use
-
Measure using a dosing syringe or spoon (not household spoons)
-
Store as directed—refrigeration may not be necessary
What If You Miss a Dose?
If a dose is missed, take it as soon as possible unless it’s close to the time for the next dose. Do not double up to make up for a missed dose.
Possible Side Effects
Nitazoxanide is generally well-tolerated, but some people may experience:
-
Nausea
-
Vomiting
-
Stomach pain
-
Headache
-
Yellow discoloration of urine or eyes (due to tizoxanide metabolite; not harmful)
Severe allergic reactions are rare but may occur. Seek immediate medical attention if you experience:
-
Rash
-
Swelling of the face or throat
-
Breathing difficulties
When to See a Doctor
You should contact a healthcare provider if:
-
Diarrhea lasts more than 3–4 days after starting treatment
-
Side effects are severe or persistent
-
The infection reoccurs shortly after treatment
-
The child is under 1 year of age—Nitazoxanide is generally not recommended for infants
Storage Instructions
-
Tablets: Store at room temperature, away from moisture
-
Oral suspension (reconstituted): Usually stable for 7 days at room temperature—verify on the label
-
Keep out of reach of children
Final Thoughts
Nitazoxanide is an effective and versatile treatment for a variety of parasitic infections in both adults and children. Correct dosing is critical for successful treatment outcomes. While the standard duration is usually 3 days, always follow your healthcare provider’s specific instructions based on the condition being treated, the patient’s age, and weight.
Whether you're treating Giardia, Cryptosporidium, or another parasitic infection, Nitazoxanide remains one of the safest options available when used appropriately.
Comments
0 comment