Adults

500 mg twice daily for 3 days. For severe or persistent infections, the duration may be extended as per physician's advice.

Elderly

No specific dosage adjustment is generally required, but caution is advised due to potential age-related decline in renal or hepatic function.

Renal_impairment

Use with caution. Although not extensively studied, a dose reduction may be considered for severe impairment. Consult a physician.

Onset

Not precisely defined for all indications, but symptom improvement can be seen within 1-2 days of treatment initiation.

Excretion

Primarily excreted via feces (tizoxanide and tizoxanide glucuronide) and to a lesser extent via urine (tizoxanide glucuronide).

Half life

Tizoxanide: approximately 1.5 hours; Tizoxanide glucuronide: approximately 10 hours.

Absorption

Rapidly absorbed after oral administration and undergoes rapid hydrolysis to its active metabolite, tizoxanide, and subsequently to tizoxanide glucuronide.

Metabolism

Extensive first-pass hepatic metabolism to its active metabolite tizoxanide and subsequent conjugation to tizoxanide glucuronide.

Warfarin and other anticoagulants

Nitazoxanide is highly protein-bound (tizoxanide >99.9%). Therefore, caution should be exercised when co-administering with other highly protein-bound drugs with narrow therapeutic indices, as it may displace them and increase their free plasma concentrations. INR monitoring is recommended for patients on warfarin.

Highly protein-bound drugs (e.g., NSAIDs, Sulfonylureas)

Potential for displacement, leading to increased plasma concentrations and risk of adverse effects of the displaced drug.