Ondansetron

Question 1

Trade name

Answer 1

Zofran

Question 2

Class

Answer 2

Antiemetic

Question 3

Actions

Answer 3

Suppresses centrally CNS stimulation to reduce vertigo, nausea and GI tract emesis

Question 4

Indication

Answer 4

• Nausea or vomiting in adults and children
• travel associated nausea and vomiting
• post operative or cancer chemotherapy nausea and vomiting
• prophylactic use in reducing opioid induced nausea
• effective in association with gastroduodenal, hepatic and biliary disease.

Question 5

Presentation

Answer 5

• Ampoule presentation 4mg in 2ml and 8mg in 4ml

- For IV and IM administration

Question 6

Pharmacodynamic Action

Answer 6

• Selective serotonin receptor antagonist of (5HT3) receptor sites in midbrain and GI tract
• Specific to serotonin receptors at nerve terminals of vagus nerve
• reduces nausea and vomiting

Question 7

Pharmacokinetic Action

Answer 7

• Absorption: Optimum bioavailability by IV
• Distribution: Plasma protein binding (75%)
• metabolism: Hepatic
• Elimination: unsure

Question 8

Side Effects

Answer 8

• Q-T interval prolongation
• hypotension
• Bradycardia
• Chest Pain
• Arrhythmias

Question 9

Drug Interactions

Answer 9

• Risk of severity of serotonin syndrome can be increased when Ondansetron is combined with Morphine
• Serotonin Syndrome is a group of symptoms that may occur following the use of certain drugs with serotonergic actions
  = Rapid onset
  = Myoclonus (twitching)
  = Headache
  = Agitation, Hypomania, Confusion, Hallucinations