Emistat 8 mg

Indications
Emistat is a selective serotonin 5-HT3 receptor antagonist, indicated for the following uses:

• Prevention of nausea and vomiting caused by initial and repeated courses of highly emetogenic cancer chemotherapy.
• Prevention and treatment of postoperative nausea and vomiting.
• Prevention of nausea and vomiting induced by radiotherapy.

• Use as per the advice of a registered healthcare professional.

Description
Emistat oral soluble film is designed to dissolve rapidly when placed on the tongue. It does not require water to dissolve and can be swallowed with saliva within 20 seconds. The active ingredient in Emistat is the racemic form of Emistat base, a selective 5-HT3 receptor antagonist. The empirical formula for Emistat is C18H19N3O, with a molecular weight of 293.3.

Pharmacology
Emistat (Ondansetron) is a potent, highly selective 5-HT3 receptor antagonist. The exact mechanism of action in controlling nausea and vomiting is not fully understood. Chemotherapy and radiotherapy can lead to the release of serotonin (5-HT) in the small intestine, triggering a vomiting reflex via 5-HT3 receptors. Ondansetron blocks this reflex. Furthermore, it may prevent emesis induced by the central mechanism in the brain, particularly the area postrema, which also responds to 5-HT3 receptor activation. While the precise mechanisms for postoperative nausea and vomiting (PONV) remain unclear, they likely share similar pathways to those involved in chemotherapy-induced nausea and vomiting (CINV).

Dosage

• Chemotherapy-Induced Nausea and Vomiting:
  Adults and Pediatric Patients (6 months to 18 years):

  • 8 mg tablet/orodispersible tablet: Three 0.15 mg/kg doses, up to 16 mg per dose.
  • 4 mg orodispersible tablet: Three 0.15 mg/kg doses, up to 16 mg per dose.
  • Injection: Three 0.15 mg/kg doses, up to 16 mg per dose, administered intravenously over 15 minutes.

• Radiotherapy-Induced Nausea and Vomiting:
  Adults:

  • 8 mg tablet/orodispersible tablet: 8 mg orally 1 to 2 hours before radiotherapy, then 8 mg orally every 8 hours for up to 5 days after treatment.
  • 4 mg orodispersible tablet: Three 0.15 mg/kg doses, up to 16 mg per dose.
  • Injection: Three 0.15 mg/kg doses, up to 16 mg per dose, infused intravenously over 15 minutes.

• Postoperative Nausea and Vomiting:
  Adults:

  • 8 mg tablet/orodispersible tablet: 16 mg given as two 8 mg tablets.
  • 4 mg orodispersible tablet: 16 mg.
  • Injection: 4 mg.
    Pediatrics (>40 kg):
  • Injection: 4 mg.
    Pediatrics (40 kg or under):
  • Injection: 0.1 mg/kg.

Oral Solution Dosage

• Chemotherapy-Induced Nausea and Vomiting:
  Adults/Geriatric/Children over 12 years:

  • Highly emetogenic chemotherapy: 30 ml (24 mg) Ondansetron Oral Solution 30 minutes before chemotherapy.
  • Moderately emetogenic chemotherapy: 10 ml (8 mg) Ondansetron Oral Solution 30 minutes before chemotherapy, followed by another 10 ml dose after 8 hours. A further 10 ml dose should be given every 12 hours for 1-2 days post-chemotherapy.
    Pediatrics (4-11 years):
  • 5 ml (4 mg) Ondansetron Oral Solution 30 minutes before chemotherapy, followed by doses at 4 and 8 hours. Three doses per day for 1-2 days after chemotherapy.

• Radiotherapy-Induced Nausea and Vomiting:
  Adults/Geriatric/Children over 12 years:

  • 10 ml (8 mg) Ondansetron Oral Solution, three times a day.
    For Total Body Irradiation:
  • 10 ml (8 mg) administered 1-2 hours before radiotherapy each day.
    For Single High-Dose Fraction Radiotherapy to the Abdomen:
  • 10 ml Ondansetron Oral Solution 1-2 hours before radiotherapy, followed by doses every 8 hours for 1-2 days post-treatment.
    For Daily Fractionated Radiotherapy to the Abdomen:
  • 10 ml (8 mg) Ondansetron Oral Solution 1-2 hours before each radiotherapy session, with subsequent doses every 8 hours.

• Postoperative Nausea and Vomiting (Adults/Geriatric/Children over 12 years):

  • 20 ml (16 mg) Ondansetron Oral Solution 1 hour before anesthesia.

Oral Soluble Film Dosage

• Chemotherapy-Induced Nausea and Vomiting:
  Highly Emetogenic Chemotherapy:
  • Adults: 24 mg (3 films of 8 mg each), 30 minutes before chemotherapy.
    Moderately Emetogenic Chemotherapy:
  • Adults and pediatric patients over 12 years: 8 mg film 30 minutes before chemotherapy, followed by another 8 mg dose 8 hours later. Administer 8 mg twice a day for 1-2 days post-chemotherapy.
  • Pediatric patients (4-11 years): 4 mg film, three times a day. First dose 30 minutes before chemotherapy, followed by doses 4 and 8 hours later. Administer 4 mg three times a day for 1-2 days after chemotherapy.
    Radiotherapy-Induced Nausea and Vomiting:
  • Adults: 8 mg film, three times a day.
    Postoperative Nausea and Vomiting:
  • Adults: 16 mg (2 films of 8 mg) 1 hour before anesthesia.

Administration
Oral Soluble Film

1. Tear open the pouch along the tear mark.
2. Place the film on top of your tongue. It will dissolve within 20 seconds.
3. Do not chew or swallow the film whole.
4. Swallow the dissolved film, with or without liquid.
5. Wash your hands after use.

Use as per the advice of a registered healthcare professional.

Interaction
Emistat does not appear to affect the liver’s cytochrome P-450 enzyme system significantly. However, drugs that induce or inhibit these enzymes may alter the metabolism of Emistat, potentially affecting its clearance and half-life. No dosage adjustment is necessary for patients taking drugs that impact these enzymes based on available data.

Contraindications

• Known hypersensitivity to Emistat or any of its components.
• Concomitant use with apomorphine.

Side Effects
Common side effects include headache, constipation, and diarrhea, typically mild or moderate. Rare side effects may include anaphylaxis, bronchospasm, tachycardia, chest pain, hypokalemia, and shortness of breath. Though some side effects, such as flushing, hiccups, and liver enzyme abnormalities, have been reported, the relationship to Emistat is unclear. There are no significant extrapyramidal reactions reported.

Pregnancy & Lactation
No carcinogenic effects were found in animal studies with Ondansetron, and it did not affect fertility or reproduction in rats. While no well-controlled studies exist for pregnant women, animal studies have shown no harm to the fetus at recommended doses. Caution is advised for use during breastfeeding, as Ondansetron is excreted in rat milk.

Precautions & Warnings
Hypersensitivity reactions have been reported in patients who are allergic to other selective 5-HT3 receptor antagonists. Emistat should not replace nasogastric suction in cases of gastric or intestinal peristalsis impairment. Postoperative use may mask progressive ileus or gastric distension.

Use in Special Populations

• Renal Impairment: No dosage adjustments are necessary for patients with renal issues.
• Hepatic Impairment: In patients with severe hepatic impairment, the maximum recommended dose is 8 mg, infused over 15 minutes.
• Pediatrics: Limited data for children under 4 years.
• Elderly: No dosage adjustment needed for patients over 65 years.

Therapeutic Class
Anti-emetic drugs

Storage Conditions
Store below 30°C in a dry place, away from light and moisture.

Pack Image of Emistat 8 mg Tablet
(Include visual of the product packaging)

Use as per the advice of a registered healthcare professional.