Emtron

Emtron

ondansetron

Manufacturer:

Agio Pharma

Distributor:

AA Medical
Full Prescribing Info
Contents
Ondansetron hydrochloride.
Description
Each ml contains: Ondansetron hydrochloride U.S.P. equivalent to Ondansetron 2 mg.
Action
Pharmacology: Pharmacodynamics: Pharmacological action: Ondansetron 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. Ondansetron blocks the initiation of this reflex. Activation of vagal afferents may also cause 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 ondansetron 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 induced nausea and vomiting are not known but there may be common pathways with cytotoxic induced nausea and vomiting. Ondansetron does not alter plasma prolactin concentrations. The role of ondansetron in opiate-induced emesis is not yet established.
Indications/Uses
Ondansetron is indicated for the management of nausea and vomiting induced by cytotoxic chemotherapy and radiotherapy, and for the prevention and treatment of post-operative nausea and vomiting (PONV).
Dosage/Direction for Use
Chemotherapy and radiotherapy: Adults: The emetogenic potential of cancer treatment varies according to the doses combinations of Chemotherapy and radiotherapy regimens used. The route administration and doses of Ondansetron should be flexible in the ranges of 8-32 mg a day and selected as shown below.
Emetogenic chemotherapy and radiotherapy: Ondansetron can be given either by rectal, oral (tablet or syrup), intravenous or intramuscular administration. For most patient receiving emetogenic chemotherapy and radiotherapy, ondansetron 8 mg should be administered as slow intravenous or intramuscular injection immediately before treatment, followed by 8 mg orally twelve hourly. To protect against delayed or prolonged emesis after the first 24 hours, oral or rectal treatment with Ondansetron should be continued for up to 5 days after a course of treatment. Highly emetogenic chemotherapy: For patient highly receiving emetogenic chemotherapy, eg. high dose cisplatin, Ondansetron can be given by rectal, intravenous or intramuscular administration. Ondansetron has been shown to be equally effective in the following dose schedules over the first 24 hours of chemotherapy. A single dose 8 mg by slow intravenous or intramuscular injection immediately before chemotherapy. A dose of 8 mg by slow intramuscular injection immediately, before chemotherapy followed by two further intravenous or intramuscular doses of 8 mg two to four apart, or by a constant infusion of 1 mg/hour for up to 24 hours. A single dose of 32 mg diluted in 50-100 ml of saline or other compatible infusion fluid and infused over not less than 15 minutes immediately before chemotherapy. The selection of regimen should be determined by the severity of the emetogen challenge. The efficacy of Ondansetron in highly emetogenic chemotherapy may be enhanced by the addition of the single intravenous dose of dexamethasone sodium phosphate, 20 mg administered prior to chemotherapy. To protect against delayed or prolonged emesis after the first 24 hours, oral or rectal treatment with Ondansetron should be continued for up to 5 days after a course of treatment.
Children: Ondansetron may be administered as a single intravenous dose of 5 mg/m2 immediately before chemotherapy, followed by 4 mg orally twelve hours later. 4 mg orally twice daily should be continued for up to 5 days after a course of treatment.
Elderly: Ondansetron is well tolerated by over 65 years and no alteration of dosage, dosing Frequency or route of administration are required.
Patients with Renal Impairment: No alteration of daily dosage or frequency of dosing, or route of administration are required.
Patients with Hepatic Impairment: Clearance of ondansetron is significantly reduced and serum half-life significantly. Prolonged in subjects with moderate or severe impairment of hepatic function. In such patients a totally daily dose of 8 mg should not be exceed.
Postoperative nausea and vomiting (PONV): Adults: For the prevention of PONV Ondansetron can be administered orally or by intravenous injections or intramuscular injection. Ondansetron may be administered as a single dose of 4 mg given by intramuscular or slow intravenous injection is recommended.
Children (aged 2 years and over): For prevention of PONV in patients having surgery performed under general anaesthesia, Ondansetron may be administered injection at a dose of 0.1 mg/kg up to a maximum of 4 mg.
There is limited data on the use of Ondansetron in the prevention and treatment of PONV in children under 2 years of age.
Patients with Renal Impairment: No alteration of daily dosage or frequency of dosing, or route of administration are required.
Patients with Hepatic Impairment: Clearance of ondansetron is significantly reduced and serum half-life significantly prolonged in subjects with moderate or severe impairment of hepatic function. In such patients a total daily dose of 8 mg should not be exceed.
Route of Administration: Emtron may be given intravenously.
Overdosage
There is no specific antidote for ondansetron overdose. Patients should be managed with appropriate supportive therapy. Individual doses as large as 150 mg and total daily dosages (three doses) as large as 252 mg have been administrated intravenously without significant adverse events. These doses are more than 10 times the recommended daily dose. In addition to the adverse events listed above, the following events have been described in the setting of ondansetron.
Overdose: *Sudden blindness* (amaurosis) of 2 to 3 minutes duration plus severe constipation occurred in one patient that was administered 72 mg of ondansetron intravenously as a single dose. Hypotension (and faintness) occurred in another patient that took 48 mg of oral ondansetron. Following infusion of 32 mg over only 4-minute period, a vasovagal episode with transient second-degree heart block was observed. In all instance, the events resolved completely.
Contraindications
Hypersensitivity to any component of the preparation.
Special Precautions
Hypersensitivity reactions have been reported in patients who have exhibited hypersensitivity to other selective 5HT3 receptor antagonists. Very rarely and predominantly with intravenous Ondansetron, transient ECG changes including QT interval prolongation have been reported. Therefore caution should be exercised in patients with cardiac rhythm or conduction disturbances, in patients treated with anti-arrhythmic agents or beta-adrenergic blocking agents and in patients with significant electrolyte disturbances. As ondansetron is known to increase large bowel transit time, patients with signs of subacute intestinal obstruction should be monitored following administration.
Use In Pregnancy & Lactation
Pregnancy: The safety of Ondansetron for use in human pregnancy has not been established. Evaluation of experimental animal studies does not indicate direct or indirect harmful effects with respect to the development of the embryo, or foetus, the course of gestation and peri- and post-natal development. However as animal studies are not always predictive of human response the use of ondansetron in pregnancy is not recommended.
Lactation: Tests have shown that ondansetron passes into the milk of lactating animals. It is therefore recommended that mothers receiving Ondansetron should not breastfeed their babies.
Adverse Reactions
Adverse events are listed below by system organ class and frequency. Frequencies are defined as: very common (≥1/10), common (≥1/100 and <1/10), uncommon ((≥1/1000 and <1/100), rare ((≥11/10000 and <1/1000) and very rare (<1/10000) including isolated reports. Very common, common and uncommon events were generally determined from post marketing spontaneous data.
The following frequencies are estimated at the standard recommended doses of ondansetron according to indication and formulation.
Immune system disorders: Rare: Immediate hypersensitivity reactions sometimes severe, including anaphylaxis.
Nervous system disorders: Very common: Headache. Uncommon: Seizures, movement disorders including extrapyramidal reactions such as dystonic reactions oculogyric crisis and dyskinesia have been observed without definitive evidence of persistent clinical sequelae. Rare: Dizziness during i. v. administration, which in most cases is prevented or resolved by lengthening the infusion period.
Eye disorders: Rare: Transient visual disturbances (eg. Blurred vision) during intravenous administration. The majority of blindness cases reported resolved within 20 minutes. Most patients had received chemotherapeutic agents which included cisplatin. Some cases of transient blindness were reported as cortical in origin.
Cardiac disorders: Uncommon: Arrhythmias, chest pain with or without ST segment depression, bradycardia.
Vascular disorders: Common: Sensation of warmth or flushing. Uncommon: Hypotension.
Respiratory, thoracic and mediastinal disorders: Uncommon: Hiccups.
Gastrointestinal disorders: Common: Constipation.
Hepatobiliary disorders: Uncommon: Asymptomatic increases in liver function tests. These events were observed commonly in patients receiving chemotherapy with cisplatin.
General disorders and administration site conditions: Common: Local i.v. injection site reactions.
Drug Interactions
There is no evidence that ondansetron either induces or inhibits the metabolism of other drugs commonly co-administered with it. Specific studies have shown that there are no pharmacokinetic interactions when ondansetron is administered with alcohol, temazepam, furosemide, tramadol, or propofol. Ondansetron is metabolized by multiple hepatic cytochrome P-450 enzymes: CYP 3A4, CYP2D6 AND CYP1A2. Due to the multiplicity of metabolic enzymes capable of metabolizing ondansetron, enzyme inhibition or reduced activity of one enzyme (e.g. CYP2D6 genetic deficiency) is normally compensated by other enzymes and should result in little or no significant change in overall ondansetron clearance or dose requirement. Phenytoin, Carbamazepine and Rifampicin: In patients treated with potent inducers of CYP3A4 (i.e. phenytoin, carbamazepine, and rifampicin), the oral clearance of ondansetron was increased and ondansetron blood concentration were decreased. Tramadol: Data from small studies indicate that ondansetron may reduce the analgesic effect of tramadol.
Storage
Store between 2°C to 30°C. Protect from light.
ATC Classification
A04AA01 - ondansetron ; Belongs to the class of serotonin (5HT3) antagonists. Used for the prevention of nausea and vomiting.
Presentation/Packing
Soln for inj (amp) 2mg/mL x 2 mL x 5's, 4 mL x 5's.
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