Index of drugs

Adults: treatment of nausea and vomiting induced by cytotoxic chemotherapy and radiotherapy as well as prevention and treatment of nausea and vomiting in the postoperative period.Children and youth: treatment of nausea and vomiting induced by chemotherapy in children ≥6 months; prevention and treatment of nausea and vomiting in the postoperative period in children ≥1 months.

1 ml of solution contains 2 mg of ondansetron (as a dihydrochloride hydrochloride). 1 ml of solution contains 3.62 mg of sodium as citrate, chloride and hydroxide.

A strong, highly selective antagonist of 5-HT serotonin receptors₃ neurons located in both peripheral and o.u.n. Chemotherapy and radiotherapy can cause the release of 5HT in the small intestine, triggering the gag reflex by stimulating the central nerve fibers through the 5-HT receptors₃. Ondansetron blocks the initiation of this reflex. Stimulation of centrifugal vagal fiber may also cause the release of 5-HT in the area located in the bottom of the fourth chamber of the brain, which can also cause vomiting of central origin. The mechanism of action of ondansetron in vomiting of the perioperative period is unknown, but it seems to be similar to that described in the case of nausea and vomiting induced by cytotoxic drugs. Ondansetron does not affect the concentration of prolactin in the blood. After intravenous infusion over 5 min C_max in the blood is about 65 ng / ml. Ondansetron is 70-76% bound to plasma proteins. It is metabolized in the liver. Less than 5% of the absorbed dose is excreted in the urine in unchanged form. T_0,5 is 3 hours. In patients with severe hepatic impairment, clearance of ondansetron is significantly reduced and the half-life extended to 15-32 hours.

Hypersensitivity to the components of the preparation. Hypersensitivity to other selective 5HT receptor antagonists₃ (e.g., granisterone, dolasterone). Co-administration of apomorphine and ondansetron (cases of profound hypotonia and loss of consciousness have been reported).

Hypersensitivity reactions have been reported in patients who have been hypersensitive to other selective 5-HT receptor antagonists₃. In case of respiratory distress, symptomatic treatment should be used and caution should be exercised because these disorders may be harbors of hypersensitivity reactions. The use of ondansetron in patients with congenital long QT syndrome should be avoided. Caution should be exercised in patients with risk factors for QT prolongation or arrhythmias: electrolyte disturbances, congestive heart failure, bradyarhythmias, use of other QT prolonging agents (including cytotoxic agents) or drugs that may lead to electrolyte imbalance and the use of drugs that reduce the frequency of rhyme. The hypokalemia and hypomagnesaemia should be corrected prior to administration of ondansetron. Ondansetron increases intestinal transit time - patients with symptoms of subacute intestinal obstruction should be observed after administration of ondansetron. In patients undergoing tonsillectomy, the use of ondansetron to prevent nausea and vomiting may mask latent bleeding - these patients should be carefully observed. Children receiving ondansetron with chemotherapeutic agents with hepatic toxicity should be closely monitored for liver dysfunction. Patients on a sodium-based diet should take into account the sodium content of the preparation (2.5 mmol, ie 57.5 mg sodium / the maximum daily dose of 32 mg).

The safety of use in pregnant women has not been established, therefore it is not recommended. It is absolutely necessary to be cautious when prescribing ondansetron to a pregnant woman, especially during the first trimester. The benefit-risk ratio should be carefully considered. In animals, it has been shown that ondansetron is excreted in milk, therefore it is recommended that mothers taking the drug do not breastfeed.

Very common: headache. Common: feeling hot, flushing, constipation.Uncommon: arrhythmias and chest pain with or without ST depression (in individual cases of death), hypotension, hiccups, hypersensitivity reactions around the injection site (eg rash, urticaria, pruritus) sometimes along the vein to which the medicine was administered, asymptomatic elevation of liver enzymes (especially in patients receiving cisplatin). Rare: immediate type hypersensitivity reactions (sometimes severe, including anaphylactic reactions that may result in death), disorders with involuntary movements (such as extrapyramidal reactions, e.g. forcible vision with ocular rotations and (or) dystonic reactions without conclusive evidence for persistent clinical consequences of such ondansetron action and rarely observed seizures), dizziness during rapid intravenous administration (which disappears after prolonged infusion time), transient visual disturbances (mainly during rapid intravenous administration), transient changes in the electrocardiogram, including prolongation of the interval QT (alsotorsade de pointes) mainly after intravenous administration. Very rare: transient blindness - mainly during intravenous administration, most incidents resolved within 20 min, most of the patients who experienced this symptom took chemotherapeutics, including Cisplatin, some cases of transient blindness were of cortical origin.

Nausea and vomiting caused by chemotherapy or radiotherapy. Adults. The route of administration of ondansetron and its dose should be chosen in a flexible way, in the range of 8-32 mg per day, according to the following recommendations.Chemotherapy and radiotherapy with emetic effects: in the majority of patients, ondansetron 8 mg should be given immediately before treatment, by slow intravenous or intramuscular injection or short 15-minute intravenous infusion, followed by 8 mg orally every 12 hours. To prevent nausea and vomiting delayed or prolonged after 24 h should be continued ondansetron orally with Dexamethasone up to 5 days after the end of the treatment cycle. Treatment with ondansetron administered by a non-intravenous route should be continued up to 5 days after the end of the treatment cycle.Chemotherapy with strong vomiting. The preparation showed comparable efficacy in the following dosing regimens during the first 24 hours after the start of chemotherapy: a single 8 mg dose given by slow intravenous or intramuscular injection immediately before chemotherapy; 8 mg immediately before chemotherapy given by slow intravenous or intramuscular injection or short intravenous infusion over 15 min, followed by two consecutive doses intravenously or intramuscularly 8 mg each, separated by 4 hours or by continuous intravenous infusion at a dose of 1 mg / h to 24 h; single dose of 16 mg diluted in 50 to 100 ml of normal saline or other compatible solution for infusion and given only as an intravenous infusion lasting not less than 15 min immediately prior to chemotherapy. A single dose of more than 16 mg should not be given due to the risk of dose-dependent QT prolongation. In patients ≥75 years, a single dose for the prophylaxis of nausea and vomiting induced by chemotherapy may not exceed 8 mg (it should be administered as an infusion lasting at least 15 minutes). Subsequent doses of ondansetron given intravenously in all adult patients should be given at intervals of not less than 4 hrs. In patients ≥65 years all intravenous doses should be diluted in 50-100 ml of saline or other compatible liquid and infused over 15 years min. The choice of dosage regimen should depend on the degree of severity of vomiting. The efficacy of ondansetron can be increased by adding a single intravenous dose of 20 mg dexamethasone phosphate sodium before chemotherapy. To prevent delayed or prolonged vomiting after the first 24 h, oral treatment should be continued up to 5 days after the end of the treatment cycle ondansetron.Children and youth (nausea and vomiting induced by chemotherapy in children ≥6 months and adolescents). The dose of ondansetron is calculated based on body surface area or body weight. The total daily doses calculated on the basis of body weight are usually greater than the doses calculated on the basis of the body surface area. There are no data on the use of the preparation in children in the event of nausea and vomiting induced by radiotherapy and in the prevention of delayed or prolonged nausea or vomiting induced by chemotherapy.The dose calculated on the basis of the body surface area. The preparation should be administered intravenously, in a single dose of 5 mg / m² pc, immediately before the start of chemotherapy. The dose administered intravenously can not exceed 8 mg. After 12 hours, ondansetron may be started orally and continued for up to 5 days. The total daily dose can not be greater than the adult dose, i.e. 32 mg. Children on pc <0.6 m²: day 1 - 5 mg / m² pc.i.v. + 2 mg in syrup or tablet after 12 hours, days 2 - 6. - 2 mg in syrup or tablet every 12 hours. Children with pc. > 0.6 m²: day 1 - 5 mg / m² pc.i.v. + 4 mg in syrup or tablet after 12 hours, days 2 - 6. - 4 mg in syrup or tablet every 12 hours.Dose calculated based on body weight. The preparation should be administered intravenously, in a single dose of 0.15 mg / kg, immediately before the start of chemotherapy. The dose administered intravenously can not exceed 8 mg. Two consecutive doses may be given intravenously at intervals of 4 hours. The total daily dose should not be greater than the adult dose, i.e. 32 mg. After 12 hours, ondansetron may be started orally and continued for up to 5 days. Children about the month of ≤10 kg: day 1 - up to 3 doses of 0.15 mg / kg every 4 hours, days 2 - 6. - 2 mg in syrup or tablet every 12 hours. Children at birth. > 10 kg: day 1 - up to 3 doses of 0.15 mg / kg every 4 hours, days 2 - 6. - 4 mg in syrup or tablet every 12 hours.Nausea and vomiting of the postoperative period. Adults. The preparation can be used in a single dose of 4 mg administered intramuscularly or by slow intravenous injection just before the introduction of anesthesia. In the postoperative period, a single dose of 4 mg administered intramuscularly or by slow intravenous injection is recommended for the treatment of nausea and vomiting.Children ≥1 months and adolescents. To prevent post-operative nausea and vomiting in children undergoing surgery under general anesthesia, the product may be administered by slow intravenous injection (lasting not less than 30 s) in a single dose of 0.1 mg / kg, up to 4 mg, before, during or after entering anesthesia. The same dose is used to treat nausea and vomiting in the postoperative period. There are no data on the use of the preparation in the treatment of post-operative nausea and vomiting in children under 2 years.Special groups of patients. In patients with renal insufficiency and in patients with slow metabolism of spartein and debrisoquine, no dosage adjustment is necessary. In patients with moderate or severe hepatic impairment, the maximum daily dose is 8 mg.