Antiemetic Drugs (Ch 83)

Question 1

What kind of agents are Antiemetic agents?

Answer 1

They are ani-nausea medications that are used a lot during cancer therapy/ treatment

Question 2

Most antirmetic drugs are?

Answer 2

-Most drugs are receptor antagonists: inhibit neurotransmitter action in vomiting reflex

Question 3

Uses for antiemetic drugs? When is it most successful to give them?

Answer 3

-Used in multiple causes of N&V

-cancer chemotherapy-induced (CINV)
-postoperative with general anesthesia
-motion sickness

-Best to give it to patient early on/before treatment or situations

Question 4

Mechanism of Action and Indications for antiemetic drugs?

Answer 4

*5-HT (serotonin) antagonists (Block 5-HT3 (serotonin) receptors in the CTZ (and VC) and GI)

Question 5

Example of a 5-HT antagonist? When are they primarily used?

Answer 5

Primarily used for patients on chemo therapy

ondansetron,

Question 6

How do Dopamine (DA) receptor antagonists work? Examples of two agents?

Answer 6

-Block DA receptors in the CTZ

Antipsychotic (Neuroleptic) agents
Prokinetic agents (increase GI motility)

Question 7

Ex of a antipsychotic DA? (dopamine recpetor antagonist)

Answer 7

chlorpromazine (antipsychotic drug)

Question 8

What agent is used for motion sickness? how is it usually administered?

Answer 8

-Scopolamine
-Administered behind the ear

Question 9

How do Anticholinergic agents work? example of one?

Answer 9

-Block acetylcholine (ACh) receptors in the inner ear labyrinth
-Block transmission of nauseating stimuli to VC
-Also block transmission of nauseating stimuli from the reticular formation to the VC

Ex.) Scopolamine

Question 10

How do Antihistamine agents work as antiemetic agents?

Answer 10

-They are receptor antagonists that block H1 recptors

They also prevent cholinergic stimulation in vestibular and reticular areas

Question 11

Example of a antihistamine that is also used as an antiemetic agent?

Answer 11

Dimenhydrinate (Gravol)