Nitazoxanide treats Giardia, Cryptosporidium, and other protozoal infections. Evaluate hypersensitivity, hepatic function, and immunocompetence before prescribing.
Absolute contraindication is hypersensitivity to nitazoxanide or formulation components. Relative contraindications include moderate-to-severe hepatic impairment, severe renal impairment, immunocompromised hosts requiring prolonged therapy, and concomitant drugs that rely on tight hepatic monitoring.
Hypersensitivity to nitazoxanide, tizoxanide metabolites, or formulation excipients — prior anaphylaxis or severe dermatologic reactions preclude rechallenge.
Moderate to severe hepatic impairment or biliary obstruction; metabolism is primarily hepatic, so product labeling recommends closer monitoring of liver enzymes and clinical status.
Renal impairment with reduced creatinine clearance; metabolites are renally eliminated and accumulation can prolong gastrointestinal adverse effects.
Immunocompromised hosts (including transplant recipients or advanced HIV) because effectiveness for Cryptosporidium is reduced — coordinate care with infectious diseases specialists and monitor stool studies.
Pregnancy and breastfeeding when alternative agents exist; human data remain limited and benefits should clearly outweigh potential fetal or neonatal risk.