Nitazoxanide warnings and precautions
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ahmed Zaghw, M.D. [2]
Precautions
General: The pharmacokinetics of nitazoxanide in patients with compromised renal or hepatic function have not been studied. Therefore, nitazoxanide must be administered with caution to patients with hepatic and biliary disease, to patients with renal disease and to patients with combined renal and hepatic disease.
Alinia Tablets and Alinia for Oral Suspension should be taken with food.
Diabetic patients and caregivers should be aware that the oral suspension contains 1.48 grams of sucrose per 5 mL.
Drug Interactions
Tizoxanide is highly bound to plasma protein (>99.9%). Therefore, caution should be used when administering nitazoxanide concurrently with other highly plasma protein-bound drugs with narrow therapeutic indices, as competition for binding sites may occur (e.g., warfarin). In vitro metabolism studies have demonstrated that tizoxanide has no significant inhibitory effect on cytochrome P450 enzymes. Although no drug-drug interaction studies have been conducted in vivo, it is expected that no significant interaction would occur when nitazoxanide is co-administered with drugs that either are metabolized by or inhibit cytochrome P450 enzymes.
Carcinogenesis, Mutagenesis, Impairment of Fertility
Long-term carcinogenicity studies have not been conducted.
Nitazoxanide was not genotoxic in the Chinese hamster ovary (CHO) cell chromosomal aberration assay or the mouse micronucleus assay. Nitazoxanide was genotoxic in 1 tester strain (TA 100) in the Ames bacterial mutation assay.
Nitazoxanide did not adversely affect male or female fertility in the rat at 2,400 mg/kg/day (approximately 20 times the clinical adult dose adjusted for body surface area).
Pregnancy: Teratogenic Effects
Pregnancy Category B: Reproduction studies have been performed at doses up to 3,200 mg/kg/day in rats (approximately 26 times the clinical adult dose adjusted for body surface area) and 100 mg/kg/day in rabbits (approximately 2 times the clinical adult dose adjusted for surface area) and have revealed no evidence of impaired fertility or harm to the fetus due to nitazoxanide. There are, however, no adequate and well-controlled studies in pregnant women.
Nursing Mothers
It is not known whether nitazoxanide is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when nitazoxanide is administered to a nursing woman.
Pediatric Use
A single Alinia Tablet contains a greater amount of nitazoxanide than is recommended for pediatric dosing and should therefore not be used in pediatric patients 11 years or younger. Alinia for Oral Suspension should be used for dosing nitazoxanide in pediatric patients (see DOSAGE AND ADMINISTRATION).
Safety and effectiveness of Alinia for Oral Suspension in pediatric patients less than 1 year of age have not been studied.
Geriatric Use
Clinical studies of Alinia Tablets and Alinia for Oral Suspension did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. In general, the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy in elderly patients should be considered when prescribing Alinia Tablets and Alinia for Oral Suspension. As stated in the PRECAUTIONS section, this therapy must be administered with caution to patients with renal and or hepatic impairment.
HIV-Infected or Immunodeficient Patients
Alinia Tablets and Alinia for Oral Suspension have not been studied for the treatment of diarrhea caused by Giardia lamblia in HIV-infected or immunodeficient patients. Alinia Tablets and Alinia for Oral Suspension have not been shown to be superior to placebo for the treatment of diarrhea caused by Cryptosporidium parvum in HIV-infected or immunodeficient patients.[1]
References
Adapted from the FDA Package Insert.