Indications of Emistat 8 mg
Emistat 8 mg is a serotonin subtype 3 (5-HT3) receptor antagonist indicated:
Prevention of nausea and vomiting associated with initial and repeat courses of emetogenic cancer chemotherapy.
Prevention and treatment of post-operative nausea and vomiting.
Prevention of radiotherapy-induced nausea and vomiting.
Theropeutic Class
Anti-emetic drugs
Pharmacology
Emistat 8 mg is a selective 5-HT3 receptor antagonist. While its mechanism of action has not been fully characterized, Emistat 8 mg is not a dopamine-receptor antagonist. Serotonin receptors of the 5-HT3 type are present both peripherally on vagal nerve terminals and centrally in the chemoreceptor trigger zone of the area postrema. It is not certain whether Emistat 8 mg's antiemetic action is mediated centrally, peripherally, or in both sites. However, cytotoxic chemotherapy appears to be associated with release of serotonin from the enterochromaffin cells of the small intestine.
Dosage & Administration of Emistat 8 mg
Prevention of chemotherapy induced nausea & vomiting (CINV):
Adult-
Tablet and oral solution: The recommended adult oral dosage of Emistat 8 mg is 24 mg given as three 8 mg tablets in highly emetogenic chemotherapy. In case of moderately emetogenic chemotherapy the oral dose is one 8 mg Emistat 8 mg tablet or 10 ml of Emistat 8 mg oral solution given twice daily.
Injection: The recommended i.v. dose of Emistat 8 mg is a single 32 mg dose or three 0.15 mg/kg doses. A single 32 mg dose is infused over 15 minutes beginning 30 minutes before the start of emetogenic chemotherapy. Subsequent doses (0.15 mg/kg) are administered 4 and 8 hours after the first dose of Emistat 8 mg.
Suppository: The recommended adult dose is one 16 mg suppository 1-2 hours before treatment. Emistat 8 mg should be continued for upto 5 days after a course of treatment.The recommended dose is one suppository daily.
Pediatric patients-
Tablet and oral solution: for pediatric patients 4 through 11 years of age the dosage is one 4 mg Emistat 8 mg tablet or 5ml of Emistat 8 mg solution should be administered 3 times a day for 1 to 2 days after completion of chemotherapy.
Injection: the dosage in pediatric patients 4 to 18 years of age should three 0.15-mg/kg doses.
Suppository:Not recommended.
Radiotherapy induced nausea and vomiting:
Adult: the recommended oral dosage is one 8mg Emistat 8 mg tablet or 10ml of Emistat 8 mg oral solution given 3 times daily.
Post operative nausea & vomiting:
Adult-
Tablet and oral solution: The recommended dosage is 16 mg given as two 8 mg Emistat 8 mg tablets or 20 ml of Emistat 8 mg oral solution 1hour before induction of anesthesia.
Injection: The recommended I.V. dosage of Emistat 8 mg for adults is 4 mg undiluted administered intravenously in not less than 30 seconds, preferably over 2 to 5 minutes, immediately before induction of anesthesia, or postoperatively if the patient experiences nausea and/or vomiting occurring shortly after surgery. Alternatively, 4 mg undiluted may be administered intramuscularly as a single injection for adults. In patients who do not achieve adequate control of postoperative nausea and vomiting following a single, prophylactic, preinduction, I.V. dose of Emistat 8 mg 4 mg, administration of a second I.V. dose of 4 mg Emistat 8 mg postoperatively does not provide additional control of nausea and vomiting.
Suppository: The recommended adult dose is one 16 mg suppository 1-2 hours before treatment. Emistat 8 mg should be continued for upto 5 days after a course of treatment.The recommended dose is one suppository daily.
Pediatric patients-
Injection: The recommended I.V. dosage of Emistat 8 mg for pediatric patients (2 to 12 years of age) is a single 0.1-mg/kg dose for pediatric patients weighing 40 kg or less, or a single 4 mg dose for pediatric patients weighing more than 40 kg. The rate of administration should not be less than 30 seconds, preferably over 2 to 5 minutes. Little information is available about dosage in pediatric patients younger than 2 years of age.
Suppository: Not recommended.
Dosage of Emistat 8 mg
Chemotherapy-Induced Nausea and Vomiting-Adults, Pediatric patients (6 months to 18 years):
8 mg tablet/orodispersible tablet: Three 0.15 mg/kg doses, up to a maximum of 16 mg per dose.
4 mg orodispersible tablet: Three 0.15 mg/kg doses, up to a maximum of 16 mg per dose.
Injection: Three 0.15 mg/kg doses, up to a maximum of 16 mg per dose, infused intravenously over 15 minutes.
Radiotherapy-Induced Nausea and Vomiting-Adults:
8 mg tablet/orodispersible tablet: Initial Dose: 8 mg orally 1 to 2 hours before radiotherapy. Post Radiotherapy: 8 mg orally every 8 hours for up to 5 days after a course of treatment.
4 mg orodispersible tablet: Three 0.15 mg/kg doses, up to a maximum of 16 mg per dose.
Injection: Three 0.15 mg/kg doses, up to a maximum of 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 mgPediatrics (40 kg): Injection: 0.1 mg/kgChemotherapy-induced Nausea and Vomiting-Adults/Geriatric/Child of 12 years or over:
Highly emetogenic cancer chemotherapy: 30 ml (24 mg) Emistat 8 mg Oral Solution administered 30 minutes before start of emetogenic chemotherapy.
Moderate emetogenic cancer chemotherapy: 10 ml (8 mg) Emistat 8 mg Oral Solution administered 30 minutes before start of emetogenic chemotherapy. A further 10 ml dose should be administered after 8 hours of the first dose. One 10 ml dose should be administered twice a day (every 12 hours) for 1-2 days after completion of chemotherapy.
Pediatric (4-11 years): 5 ml (4 mg) Emistat 8 mg Oral Solution should be taken 30 minutes before the start of chemotherapy. The other 2 doses should be taken 4 and 8 hours after the first dose. Then 5 ml oral solution should be administered 3 times a day (every 8 hours) for 1-2 days after completion of chemotherapy.
Oral solution:
Radiotherapy induced Nausea and Vomiting (Adults/Geriatric/Child of 12 years or over):
The recommended oral dosage: 10 ml (8 mg) Emistat 8 mg Oral Solution 3 times daily.
For total body irradiation: 10 ml (8-mg) Emistat 8 mg Oral Solution should be administered 1 to 2 hours before each fraction of radiotherapy administered each day.
For single high-dose fraction radiotherapy to the abdomen: one 10 ml Emistat 8 mg Oral Solution should be administered 1 to 2 hours before radiotherapy, with subsequent doses every 8 hours after the first dose for 1 to 2 days after completion of radiotherapy.
For daily fractionated radiotherapy to the abdomen: 10 ml (8-mg) Emistat 8 mg Oral Solution should be administered 1 to 2 hours before radiotherapy, with subsequent doses every 8 hours after the first dose for each day radiotherapy is given.
Postoperative Nausea and Vomiting (Adults/Geriatric/Child of 12 years or over):
20 ml (16 mg) Emistat 8 mg Oral Solution 1 hour before induction of anesthesia
Oral Soluble Film:
Prevention of nausea and vomiting associated with highly emetogenic cancer chemotherapy:
Adult oral dose: 24 mg given successively as three 8 mg films 30 minutes before the start of chemotherapy.
Prevention of nausea and vomiting associated with moderately emetogenic cancer chemotherapy:
Adults and pediatric patients 12 years of age and older: One 8 mg film 30 minutes before chemotherapy followed by an 8 mg dose 8 hours later. Administer one 8 mg film twice a day (every 12 hours) for 1 to 2 days after completion of chemotherapy.
Pediatric patients 4 through 11 years of age: One 4 mg film three times a day. Administer the first dose 30 minutes before chemotherapy, with subsequent doses 4 and 8 hours later. Administer one 4 mg film three times a day (every 8 hours) for 1 to 2 days after completion of chemotherapy.
Prevention of nausea and vomiting associated with radiotherapy: The adult dosage is one 8 mg film three times a day.
Postoperative nausea and vomiting: The adult dose is 16 mg given successively as two 8 mg films 1 hour before anesthesia.
Administration of Emistat 8 mg
Administration of Oral Soluble Film:
Step 1: Tear the pouch carefully along with the edge tear mark.
Step 2: Put the Emistat 8 mg film on top of your tongue. It will dissolve within 20 seconds
Step 3: Do not chew or swallow the film whole.
Step 4: Swallow after the Onsaf oral soluble film dissolves. You may swallow the dissolved film with or without liquid.
Step 5: Wash your hands after taking Onsaf oral soluble film
Interaction of Emistat 8 mg
Emistat 8 mg does not itself appear to induce or inhibit the cytochrome P-450 drug-metabolizing enzyme system of the liver. Because Emistat 8 mg is metabolized by hepatic cytochrome P-450 drug-metabolizing enzymes, inducers or inhibitors of these enzymes may change the clearance and hence, the half-life of Emistat 8 mg. On the basis of available data, no dosage adjustment of Ondasetron is recommended for patients on these drugs.
Contraindications
Contraindicated in patients known to have hypersensitivity to the drug or any of its components. Concomitant use of apomorphine.
Side Effects of Emistat 8 mg
Frequently reported adverse events were headache, constipation and diarrhea, but the majority have been mild or moderate in nature. In chemotherapy-induced nausea and vomiting, rash has occurred in approximately 1% of patients receiving Emistat 8 mg. There also have been reports to a sensation of flushing or warmth, hiccups and liver enzyme abnormalities. Rare cases of anaphylaxis, brochospasm, tachycardia, angina (chest pain), hypokalemia, shortness of breath have also been reported, except for bronchospasm and anaphylaxis, the relationship to Emistat 8 mg is unclear. There have been no evidence to extrapyramidal reactions, in rare case oculogyric crisis appearing alone, as well as with other dystonic reactions without definitive clinical evidence. In case of PONV, with the exception of headache, rates of these events were not significantly different in the Emistat 8 mg and placebo groups.
Pregnancy & Lactation
Pregnancy category B. Reproduction studies at daily oral dose up to 10 and 30 mg/kg/day have been performed in animals and have revealed no evidence of impaired fertility harm to the fetus due to Emistat 8 mg. There are, however, no adequate and well-controlled studies in pregnant women. So the drug should be used in pregnancy only if clearly needed. Emistat 8 mg excretes in milk of lactating animals. Caution should be exercised when Emistat 8 mg is administered to nursing mother.
Precautions & Warnings
Hypersensitivity reactions have been reported in patients who have exhibited hypersensitivity to other selective 5-HT3 receptor antagonists. Emistat 8 mg is not a drug that stimulates gastric or intestinal peristalsis. It should not be used instead of nasogastric suction. The use of Emistat 8 mg in patients following abdominal surgery or in patients with chemotherapy-induced nausea and vomiting may mask a progressive ileus and/or gastric distension.
Overdose Effects of Emistat 8 mg
There is no specific antidote for Emistat 8 mg overdose. In addition to the adverse events, hypotension (and faintness) occurred in a patient that took 48 mg of AVONA tablets. In all instances, the events resolved completely.
Storage Conditions
Store at temperature not exceeding 30ºC in a dry place. Protect from light and moisture.
Use In Special Populations
Pediatric use: Can be given in children 1 month of age and above. Geriatric use: No dosage adjustment is necessary in the elderly.Dosage adjustment for patients with impaired hepatic function:
Tablet and Oral Solution: The total daily dose of 8 mg should not be exceeded.
Injection: A single maximal dose of 8 mg to be infused over 15 minutes beginning 30 minutes before the start of the emetogenic chemotherapy is recommended.
Suppository: Not recommended
Reconstitution
Prior to IV infusion, dilute in 50 ml dextrose 5% inj or normal saline.
Drug Classes
Anti-emetic drugs
Mode Of Action
Emistat 8 mg is a potent, highly selective 5HT3 receptor-antagonist. Its precise mode of action in the control of nausea and vomiting is not known. Chemotherapeutic agents and radiotherapy may cause release of 5HT in the small intestine initiating a vomiting reflex by activating vagal afferents via 5HT3 receptors. Emistat 8 mg blocks the initiation of this reflex. Activation of vagal afferents may also cause a release of 5HT in the area postrema, located on the floor of the fourth ventricle, and this may also promote emesis through a central mechanism. Thus, the effect of Emistat 8 mg in the management of the nausea and vomiting induced by cytotoxic chemotherapy and radiotherapy is probably due to antagonism of 5HT3 receptors on neurons located both in the peripheral and central nervous system. The mechanisms of action in post-operative nausea and vomiting are not known but there may be common pathways with cytotoxic induced nausea and vomiting.
Pregnancy
Carcinogenic effects were not seen in 2-year studies in rats and mice with oral Emistat 8 mg doses up to 10 and 30 mg/kg per day, respectively. Emistat 8 mg was not mutagenic in standard tests for mutagenicity. Oral administration of Emistat 8 mg up to 15 mg/kg per day did not affect fertility or general reproduction performance of male and female rats.Reproduction studies have been performed in pregnant rats and rabbits at daily oral doses up to 15 and 30 mg/kg per day, respectively, and have revealed no evidence of impaired fertility or harm to the fetus due to Emistat 8 mg. There are, however, no adequate and well-controlled studies in pregnant women. Emistat 8 mg is excreted in the breast milk of rats. So caution should be exercised when Emistat 8 mg is administered to a nursing women.
Pediatric Uses
Dosage Adjustment for Patients With Impaired Renal Function: The dosage recommendation is the same as for the general population.Dosage Adjustment for Patients With Impaired Hepatic Function: In patients with severe hepatic impairment, a single maximal daily dose of 8 mg to be infused over 15 minutes beginning 30 minutes before the start of the emetogenic chemotherapy is recommended.4 years of age or younger: Little information is available about dosage in pediatric patients 4 years of age or younger.Over the age of 65: Dosage adjustment is not needed in patients over the age of 65.