Ondansetron-Altpharm - instructions for use, dose, side effects, contraindications

Ondansetron is a selective antagonist of the 5HT3 (serotonin) receptor. Drugs for cytostatic chemotherapy and radiotherapy can cause an increase in the level of serotonin, which by activation of vagal afferent fibers containing receptors 5-HT₃, causes a vomitive reflex. Ondansetron inhibits the appearance of a vomiting reflex by blockade of receptors 5-HT₃ at the level of neurons of both the central and peripheral nervous system.

Apparently, this mechanism of action is based on the prevention and treatment of post-operative and cytostatic chemo- and radiotherapy-induced vomiting and nausea.

Pharmacokinetics:

After rectal administration ondansetron is determined in the plasma after 15-60 minutes. The concentration of the active substance increases linearly, the maximum concentration is achieved approximately after 6 h and is 20-30 ng / ml.Absolute bioavailability for rectal administration is approximately 60%.

Reduction in plasma concentration occurs at a lower rate than after oral administration (due to continued absorption). Half-life - 6 hours. The pharmacokinetic parameters of ondansetron do not change with its repeated administration.

Indications:

Prevention and elimination of nausea and vomiting caused by cytostatic chemotherapy and radiotherapy.

Contraindications:

- Hypersensitivity to ondansetron or any other component of the drug

- Pregnancy and lactation.

- Childhood.

Dosing and Administration:

The drug is used rectally. To remove the suppository from the cell package, one cell with a suppository must be broken off by notching and disconnecting the edges of the tape, pulling them in different directions. The suppository is inserted into the anus with a pointed end, as deep as possible. For a more convenient introduction of the suppository, it is recommended to bend down, squat or lie on one side, with your legs tucked.

The choice of the dosage regimen is determined by the severity of the emetogenic effect of the antitumor therapy.

With moderate emetogenic chemotherapy or radiotherapy:

- 16 mg ondansetron for 1-2 h before the start of the main therapy.

With highly emeticogenic chemotherapy:

The recommended dose is 16 mg concomitantly with intravenous administration of 20 mg dexamethasone for 1 -2 hours before the start of chemotherapy.

To prevent late or prolonged vomiting that occurs 24 hours after the end of chemotherapy or radiotherapy, you should continue taking the drug at a dose of 16 mg once a day for 5 days.

Children. Ondansetron in suppositories is not recommended for use in children.

Patients of advanced age. Dosage adjustments are not required.

Patients with renal insufficiency. No special changes in dosage, frequency or method of administration are required.

Patients with impaired hepatic function. The daily dose of ondansetron for this category of patients should not exceed 8 mg per day.

Patients with a slow metabolism of sparteine / debrisoquine. Correction of a daily dose or frequency of ondansetron is not required.

Side effects:

Allergic reactions: urticaria, bronchospasm, laryngospasm, angioedema, anaphylaxis.

From the digestive system: hiccough, dry mouth, constipation or diarrhea, sometimes an asymptomatic transient increase in serum aminotransferase activity.

From the side of the cardiovascular system: pain in the chest, in some cases with depression of the segment ST, arrhythmias, bradycardia, lowering blood pressure.

From the nervous system: headache, dizziness, spontaneous movement disorders and convulsions.

Local Reactions: hyperemia, pain, a burning sensation in the anus and rectum after the introduction of the suppository

Other: "tide" of blood to the skin of the face, a feeling of heat, a temporary disturbance of visual acuity, hypokalemia, hypercreatininaemia.

Overdose:

There is limited experience of overdose ondasetron. In most cases, the symptoms are similar to adverse reactions when the drug is administered at recommended doses.

Treatment: symptomatic and supportive therapy. The specific antidote for ondansetron is not known.

Interaction:

There is no evidence that ondansetron induces or inhibits the metabolism of other drugs, often prescribed in combination with it.

Ondansetron is metabolized by several enzymes of the cytochrome P system450 (CYP3A4, CYP2D6 and CYP1A2): The inhibition or decrease in the activity of one of the enzymes is usually normally compensated by others, and therefore a significant reduction in the overall clearance of ondansetron is unlikely. However, caution is required when using together:

- with enzymatic inducers P450 (CYP2D6 and CYP3A) (barbiturates, carbamazepine, carisoprodol, glutethimide, griseofulvin, dinitrogen oxide, papaverine, phenylbutazone, phenytoin (probably other hydantoins), rifampicin, tolbutamide);

- with inhibitors of enzymes P450 (CYP2D6 and CYP3A) (allopurinol, macrolide antibiotics, antidepressants - MAO inhibitors, chloramphenicol, cimetidine, oral contraceptives containing estrogens, diltiazem, disulfiram, valproic acid, sodium valproate, erythromycin, fluconazole, fluoroquinolones, isoniazid, ketoconazole, lovastatin, metronidazole, omeprazole, propranolol, quinidine, quinine, verapamil).

Special studies have shown that ondansetron does not interact with alcohol, temazepam, furosemide, tramadol and propofol.

Special instructions:

Patients who had previously had allergic reactions to other selective blockers 5-HT₃- receptors, have an increased risk of their development against the background of ondansetron. Ondansetron can slow the motility of the large intestine, in connection with which, its appointment to patients with signs of intestinal obstruction requires special observation.

Form release / dosage:

Suppository rectal by 4 mg, 8 mg and 16 mg.

Packaging:

For 5 pieces (suppositories of 4 mg or 8 mg) in a contiguous cell pack of a polyvinyl chloride film. One contour pack together with instructions for use in a pack of cardboard.

1 suppository (16 mg) in a contiguous cell package. One outline package in a cardboard insert. Two cardboard inserts together with instructions for use in a pack of cardboard.

Storage conditions:

In dry, dark place at a temperature of no higher than 25 ° C.

Keep out of the reach of children.

Shelf life:

2 of the year. Do not use after the expiration date printed on the package.

Terms of leave from pharmacies:On prescription

Registration number:LSR-005842/08

Date of registration:23.07.2008

Expiration Date:Unlimited

The owner of the registration certificate:ALTFARM, LLC ALTFARM, LLC Russia

Manufacturer: & nbsp

ALTFARM, LLC Russia

Representation: & nbspALTFARM LLC ALTFARM LLC Russia

Information update date: & nbsp07.06.2017

Illustrated instructions

Instructions

Ondansetron-Altpharm (Ondansetron-Altpharm)