Nitazoxanide (Nizonide) Dosage and Treatment Plan for Parasitic Infections
For parasitic infections, nitazoxanide should be administered for 3 days, with dosing based on age: 100 mg twice daily for children 1-3 years, 200 mg twice daily for children 4-11 years, and 500 mg twice daily for individuals 12 years and older. 1, 2
Dosage Recommendations by Age Group
- Children 1-3 years old: 100 mg (5 mL of suspension) twice daily for 3 days 1, 2
- Children 4-11 years old: 200 mg (10 mL of suspension) twice daily for 3 days 1, 2
- Adolescents ≥12 years and adults: 500 mg tablet twice daily for 3 days 2
Effectiveness for Specific Parasitic Infections
Giardia lamblia
- Clinical response rates of 85-100% in adults and adolescents when administered for 3 days 2
- In pediatric patients, clinical response rate of 85% (intent-to-treat analysis) and 90% (per protocol analysis) 2
- Comparable efficacy to metronidazole but with shorter treatment duration (3 days vs. 5 days) 2, 3
Cryptosporidium
- Effective in immunocompetent patients with response rates of 56-96% depending on age and immune status 1, 2
- Less effective in HIV-infected patients with low CD4 counts (<50/μL) 1
- Should be combined with effective antiretroviral therapy in HIV-infected patients 1
Other Parasites
- Effective against Entamoeba histolytica with 94% clinical response rate 4
- Has shown efficacy against Enterocytozoon bieneusi infection in HIV-infected adults 1
- Effective against various helminths including Taenia saginata (beef tapeworm) with 98% cure rate 5
Administration Guidelines
- Nitazoxanide should always be administered with food 2
- For oral suspension: shake well before each administration 2
- The reconstituted suspension may be stored at room temperature for up to 7 days 2
Treatment Considerations
- Clinical response should be evaluated 4-7 days following the end of treatment 2
- A "well" clinical response is defined as "no symptoms, no watery stools and no more than 2 soft stools with no hematochezia within the past 24 hours" or "no symptoms and no unformed stools within the past 48 hours" 2
- Some patients with clinical improvement may still have parasites in stool samples after treatment; management should be based on clinical response 2
Supportive Care
- Maintain adequate hydration and correct electrolyte abnormalities 1
- Continue age-appropriate nutrition during treatment 1
- Antimotility agents should be used with caution, especially in young children 1
Common Pitfalls and Caveats
- Nitazoxanide may be less effective in severely immunocompromised patients, particularly those with AIDS and low CD4 counts 1, 2
- For cryptosporidiosis in HIV-infected patients, immune reconstitution through antiretroviral therapy is crucial for clearance of infection 1
- The drug is generally well-tolerated with minimal side effects (primarily mild abdominal pain) 6, 3
- For treatment failures, consider alternative agents or extended treatment courses 1, 7