Ondansetron is an antiemetic medication that blocks the actions of chemicals in the body that can trigger nausea and vomiting. Ondansetron acts by blocking one of the body's natural substances (serotonin). Ondansetron is used in preventing nausea and vomiting that can be caused by surgery, cancer chemotherapy, or radiation treatment.
Prevention and treatment of post-operative nausea and vomiting.
Selective 5-HT3 receptor antagonist binds to 5-HT3 receptors both in periphery and in CNS, with primary effects in GI tract. It has no effect on dopamine receptors and therefore does not cause extrapyramidal symptoms.
Ondansetron starts showing its action within half an hour to 2 hours. It dissolves quickly into the bloodstream and starts showing its effect.
Absorption:
Bioavailability- 56-71% (PO). Food increases extent of absorption (17%).
Distribution:
It is 70-76% protien bound.
Metabolism:
Mostly hepatic metabolism, with hydroxylation followed by glucuronide or sulfate conjugation, metabolized by CYP2D6 and partly by CYP1A2 and CYP3A4.
Elimination:
Half-life: 2-7 hr (children <15 years); 3-7 hr (adults); patients with mild to moderate hepatic impairment, 12 hr; patients with severe hepatic impairment (Child-Pugh class C), 20 hr
Primarily excreated by urine(30-70%)
Fatigue
Headache
Constipation
Diarrhea
Hypoxia
If you vomit within one hour of taking a dose, take another dose.
Avoid heavy meals and try eating small nourishing snacks throughout the day. Also, sip water regularly to help avoid dehydration.
This medicine may cause serious allergic reactions, including anaphylaxis
This medicine may make you dizzy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
Tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding
Hypersensitivity to the ondansetron or to any of the excipients.
Hypersensitivity to other selective 5-HT3 receptor antagonists.
| Ondansetron | 4 mg |