Zofra ODT 4 mg

Description

Zofra ODT (Ondansetron) Product Description

Indications Zofra ODT is a serotonin 5-HT3 receptor antagonist used for:

• Preventing nausea and vomiting caused by initial and repeated courses of emetogenic cancer chemotherapy.
• Preventing and managing post-operative nausea and vomiting.
• Preventing nausea and vomiting induced by radiotherapy.

Description Zofra ODT oral soluble film is an orally dissolving film designed to be placed on the tongue, where it dissolves within 20 seconds and is then swallowed with saliva. It does not require water for dissolution or swallowing. The active ingredient, Ondansetron, is a selective serotonin 5-HT3 receptor antagonist with the empirical formula C18H19N3O and a molecular weight of 293.3.

Pharmacology Ondansetron is a highly selective and potent 5-HT3 receptor antagonist. While its exact mechanism in controlling nausea and vomiting is not fully understood, it is believed to work by blocking the initiation of the vomiting reflex. Chemotherapy and radiotherapy can trigger the release of serotonin (5-HT) in the small intestine, activating vagal afferents through 5-HT3 receptors and initiating vomiting. Ondansetron prevents this reflex. Additionally, serotonin release in the area postrema of the brainstem may also contribute to vomiting, and Ondansetron helps block this pathway as well. The exact mechanism in post-operative nausea and vomiting remains unclear but is thought to involve similar pathways.

Dosage & Administration

Chemotherapy-Induced Nausea and Vomiting:

• Adults & Pediatric Patients (6 months–18 years):
  • Tablet/Orodispersible tablet: Three doses of 0.15 mg/kg, with a maximum of 16 mg per dose.
  • Injection: Three doses of 0.15 mg/kg (max 16 mg per dose) infused over 15 minutes.

Radiotherapy-Induced Nausea and Vomiting:

• Adults:
  • Tablet/Orodispersible tablet: 8 mg taken orally 1-2 hours before radiotherapy, followed by 8 mg every 8 hours for up to 5 days.
  • Injection: Three doses of 0.15 mg/kg (max 16 mg per dose) infused over 15 minutes.

Postoperative Nausea and Vomiting:

• Adults:
  • Tablet/Orodispersible tablet: 16 mg (two 8 mg tablets).
  • Injection: 4 mg.
• Pediatrics (>40 kg):
  • Injection: 4 mg.
• Pediatrics (<40 kg):
  • Injection: 0.1 mg/kg.

Oral Solution:

• Chemotherapy-Induced Nausea and Vomiting:
  • Adults/Geriatric/Children (≥12 years):
    • Highly emetogenic chemotherapy: 30 ml (24 mg) taken 30 minutes before chemotherapy.
    • Moderately emetogenic chemotherapy: 10 ml (8 mg) taken 30 minutes before chemotherapy, with additional doses every 8 hours for 1-2 days post-chemotherapy.
  • Children (4-11 years):
    • 5 ml (4 mg) taken 30 minutes before chemotherapy, followed by doses 4 and 8 hours later, then every 8 hours for 1-2 days post-chemotherapy.
• Radiotherapy-Induced Nausea and Vomiting (Adults/Geriatric/Children ≥12 years):
  • 10 ml (8 mg) taken 1-2 hours before radiotherapy, with subsequent doses every 8 hours for 1-2 days post-radiotherapy.
• Postoperative Nausea and Vomiting (Adults/Geriatric/Children ≥12 years):
  • 20 ml (16 mg) taken 1 hour before anesthesia.

Oral Soluble Film:

• Prevention of Chemotherapy-Induced Nausea and Vomiting:
  • Adults: 24 mg (three 8 mg films) taken 30 minutes before chemotherapy.
  • Children (12+ years): 8 mg film taken 30 minutes before chemotherapy, with another dose 8 hours later, then every 12 hours for 1-2 days.
  • Children (4-11 years): 4 mg film taken 30 minutes before chemotherapy, followed by doses 4 and 8 hours later, then every 8 hours for 1-2 days.
• Prevention of Radiotherapy-Induced Nausea and Vomiting:
  • Adults: One 8 mg film three times daily.
• Prevention of Postoperative Nausea and Vomiting:
  • Adults: 16 mg (two 8 mg films) taken 1 hour before anesthesia.

Administration of Oral Soluble Film:

1. Tear open the pouch along the edge tear mark.
2. Place the film on top of the tongue.
3. Allow the film to dissolve within 20 seconds without chewing or swallowing it whole.
4. Swallow the dissolved film with or without liquid.
5. Wash hands after handling the film.

Interactions Ondansetron does not significantly induce or inhibit hepatic cytochrome P-450 enzymes. However, since it is metabolized by these enzymes, concurrent use of enzyme inducers or inhibitors may affect its clearance and half-life. No dosage adjustment is typically required.

Contraindications

• Hypersensitivity to Ondansetron or any of its components.
• Concurrent use with apomorphine.

Side Effects Common adverse effects include:

• Headache
• Constipation
• Diarrhea
• Rash (in ~1% of chemotherapy patients)
• Flushing, hiccups, and liver enzyme abnormalities

Rare but serious effects include:

• Anaphylaxis
• Bronchospasm
• Tachycardia
• Chest pain (angina)
• Hypokalemia
• Shortness of breath
• Oculogyric crisis (rare dystonic reaction)

Pregnancy & Lactation

• Animal studies have shown no evidence of fetal harm at high doses, but there are no well-controlled studies in pregnant women.
• Ondansetron is excreted in rat breast milk, so caution is advised when administering to nursing mothers.

Precautions & Warnings

• Patients with a history of hypersensitivity to other 5-HT3 receptor antagonists may also react to Ondansetron.
• Not a substitute for nasogastric suction in patients with gastrointestinal obstruction.
• May mask symptoms of progressive ileus or gastric distension in post-operative and chemotherapy patients.

Use in Special Populations

• Renal Impairment: No dosage adjustment required.
• Hepatic Impairment: In severe hepatic impairment, a maximum single daily dose of 8 mg is recommended.
• Pediatrics (<4 years): Limited data available on dosage.
• Elderly (>65 years): No dosage adjustment needed.

Therapeutic Class Anti-emetic drugs.

Storage Conditions

• Store in a dry place at a temperature not exceeding 30°C.
• Protect from light and moisture.
• Keep out of reach of children.