ZORON 8/MG TAB 10/TAB

Indications

Approved Uses

Prevention of nausea and vomiting associated with cancer chemotherapy; prevention of nausea and vomiting associated with radiotherapy; prevention of postoperative nausea and vomiting (PONV).

Dosage & Administration

Dosing by Condition

Chemotherapy-induced N/V (adult oral): 8 mg 30 minutes before chemotherapy, then 8 mg 8 hours later; thereafter 8 mg every 12 hours for 1-2 days (moderately emetogenic). For highly emetogenic chemotherapy: 24 mg orally 30 minutes before chemotherapy (typically with dexamethasone). Radiotherapy-induced N/V: 8 mg 1-2 hours before radiotherapy, then 8 mg every 8 hours after (duration varies by fractionation). PONV prophylaxis: 16 mg orally 1 hour before induction of anesthesia.

Initial Dose

8 mg orally 30 minutes before chemotherapy or radiotherapy

Maintenance Dose

8 mg every 12 hours for 1 to 2 days after completion of chemotherapy (for moderately emetogenic chemotherapy); dosing intervals vary by indication

Maximum Dose

Oral: up to 24 mg as a single dose for highly emetogenic chemotherapy (adult); do not exceed 24 mg/day for oral dosing in typical regimens (8 mg BID is common for other indications).

Children's Dosage

4 to 11 years (moderately emetogenic chemotherapy): 4 mg 30 min before chemo, then 4 mg at 4 and 8 hours, then 4 mg every 8 hours for 1-2 days; 12-17 years: adult dose (8 mg).

Dose Adjustment Notes

Severe hepatic impairment (Child‑Pugh ≥10/Child‑Pugh C): total daily dose should not exceed 8 mg. No dosage adjustment is required in renal impairment.

How to Take

Swallow the 8 mg film‑coated tablet whole with water; may be taken with or without food. For prevention of CINV/RINV/PONV, administer at the timing specified for the indication (e.g., before chemotherapy/radiotherapy or before anesthesia) per the prescribed regimen.

Side Effects

Common Side Effects

Headache, constipation, diarrhea, dizziness (and sometimes fatigue); less commonly somnolence/drowsiness. (Injection-site reactions apply only to parenteral formulations.)

Side Effect Frequency

Very common: headache. Common: constipation, diarrhea, fatigue/malaise, dizziness. QT prolongation/arrhythmias and hypersensitivity are uncommon/rare but clinically important.

Safety & Warnings

Contraindications

Hypersensitivity to ondansetron (or other 5‑HT3 antagonists) and concomitant use with apomorphine; avoid/use contraindicated in congenital long QT syndrome per many product labels due to QT risk.

Warnings & Precautions

QT prolongation risk (avoid in congenital long QT; caution with electrolyte abnormalities, heart failure, bradyarrhythmias, and QT‑prolonging drugs; correct hypokalemia/hypomagnesemia); serotonin syndrome risk with serotonergic agents; may mask progressive ileus/gastric distension; caution in hepatic impairment.

Age Restriction

Oral ondansetron tablets: approved for children 4 years and older for chemotherapy-induced nausea/vomiting (4-11 years: 4 mg; ≥12 years: adult dose); safety and efficacy not established in children <4 years.

Driving Warning

May Cause Drowsiness

Drug Interactions

Drug Interactions

Key interactions: apomorphine (contraindicated); other QT‑prolonging drugs (additive QT risk); serotonergic drugs (SSRI/SNRI/MAOI, tramadol, etc.-serotonin syndrome risk); strong CYP3A4 inducers (phenytoin, carbamazepine, rifampin-reduced ondansetron exposure/efficacy).

Interaction Severity

MAJOR/Contraindicated: apomorphine (risk of profound hypotension and loss of consciousness). MODERATE: other serotonergic drugs (e.g., SSRIs/SNRIs/MAOIs, linezolid, triptans) due to serotonin syndrome risk; QT‑prolonging drugs and risk factors (additive QT prolongation/torsades risk). MINOR: strong CYP inducers (e.g., rifampin, phenytoin, carbamazepine) may reduce ondansetron exposure; tramadol may have reduced analgesic effect and additive serotonergic risk (generally moderate/clinical monitoring).

Special Populations

Breastfeeding

Caution

Children

4 to 11 years (moderately emetogenic chemotherapy): 4 mg 30 min before chemo, then 4 mg at 4 and 8 hours, then 4 mg every 8 hours for 1-2 days; 12-17 years: adult dose (8 mg).

Elderly

Standard adult dosing - no routine dose reduction required, but use with caution due to increased risk of QT prolongation

Kidney Impairment

No adjustment needed

Liver Impairment

Severe hepatic impairment (Child‑Pugh C or score ≥10): maximum total daily dose 8 mg; mild-moderate impairment: no adjustment.

Storage & Patient Advice

Overdose

Symptoms may include visual disturbances/transient blindness, severe constipation, hypotension/vasovagal episodes, and cardiac conduction effects including QT prolongation/arrhythmias; management is supportive/symptomatic (no specific antidote) and dialysis is unlikely to help.

Monitoring Requirements

ECG monitoring in patients with risk factors for QT prolongation (e.g., congenital long QT, CHF, bradyarrhythmias) or when used with other QT‑prolonging drugs; monitor/correct electrolytes (K+, Mg2+) in at‑risk patients.

Pharmacology

Half-Life

Approximately 3-6 hours in adults (commonly ~5-6 hours).

Bioavailability

Approximately 60%.

Metabolism

Extensive hepatic metabolism primarily via CYP3A4, CYP2D6, and CYP1A2 (multiple pathways; no single enzyme predominates).

Product Information

Available Dosage Forms

Ondansetron is available (by product line, depending on market) as film‑coated tablets, orally disintegrating tablets, oral solution, and injection (IV/IM). For ZORON specifically per SFDA: film‑coated tablet.

Composition per Dose

Each film-coated tablet: 8 mg ondansetron (as ondansetron hydrochloride dihydrate)

Generic Availability

Yes

Gi Condition

Nausea/Vomiting

Legal Disclaimer - Al Mujtama Pharmacy

The product information provided is derived from verified pharmaceutical references and is intended for general health education only. It is not a substitute for professional medical advice, diagnosis, or treatment.

Al Mujtama Pharmacy assumes no legal or medical liability for:

• Any therapeutic decision made based on the information displayed without consulting a licensed physician or pharmacist
• Any discrepancy between the information provided and the product's package insert or SFDA guidelines
• Any misuse of medication resulting from personal interpretation of the content displayed

Important notice: Drug formulations and instructions may vary between production batches. Always rely on the leaflet included inside the product packaging you have, and consult your pharmacist or physician before starting, adjusting, or discontinuing any medication.

By using this content, you acknowledge that you have read this disclaimer and agree that Al Mujtama Pharmacy bears no liability arising from reliance on this information as a substitute for direct medical consultation.

Your health is a trust - always consult your doctor first.