Antiemetics

Question 1

Dexamethasone Class

Answer 1

Synthetic glucocorticoid steroid

Question 2

Dexamethasone Uses

Answer 2

Decreasing risk for

• PONV
• Edema (e.g. airway, cerebral)
• Postoperative pain

Question 3

Dexamethasone MOA

Answer 3

Anti-inflammatory that inhibits the release of arachidonic acid, which is a precursor to mediators of inflammation (prostaglandins and leukotrienes)
*Most potent steroid

Question 4

Dexamethasone Doses

Answer 4

4 – 12 mg IV

Question 5

Dexamethasone Metabolism

Answer 5

Liver to inactive metabolites

Question 6

Dexamethasone Excretion

Answer 6

Kidneys

Question 7

Dexamethasone Admin Considerations (3)

Answer 7

Causes

• delayed wound healing
• HPA axis suppression
• hyperglycemia

Question 8

Dexamethasone Onset and DOA

Answer 8

Onset: Rapid
DOA: Usually short but can be up to
72 hours

Question 9

Ondansetron Class

Answer 9

5-HT3 (serotonin) receptor antagonist

Question 10

Ondansetron MOA

Answer 10

Inhibits serotonin both peripherally on vagus nerve terminals and centrally in the medulla’s chemoreceptor trigger zone

Question 11

Ondansetron Dosing

Answer 11

4 – 8 mg IV

Question 12

Ondansetron Uses (3)

Answer 12

PONV

Chemotherapy N/V

Carcinoid syndrome

Question 13

Ondansetron Admin Considerations (4)

Answer 13

Can causes

• Headache
• Prolonged QT interval

Can mask progressive ileus or gastric distention

R/f serotonin syndrome

Question 14

Ondansetron Onset and DOA

Answer 14

Onset: around 30 min

Half-Life Elimination: 3-6 hours