Antiemetic agents

emetics

• Agents used to induce vomiting

• No longer recommended for at-home poison control

antiemetics

• Decrease or prevent nausea and vomiting

• Centrally acting or locally acting

• Varying degrees of effectiveness

what is the prototype for the classification phenothiazines

promethazine

what is the classification for the prototype promethazine

phenothiazines

promethazine therapeutic actions

• Change responsiveness or stimulation of the CTZ in the medulla

• Most work as dopamine agonists

• Histamine receptor blocker; has dopaminergic

effects

promethazine adverse effects

• Drowsiness, dizziness, weakness, tremor, headache

• Hypotension, cardiac arrhythmias

• Autonomic effects

• Extrapyramidal symptoms

• Endocrine effects

• Photosensitivity

promethazine drug-drug interactions

CNS depressants, alcohol

promethazine contraindications

• Coma, severe CNS depression, brain damage or injury

• Severe hypotension or hypertension

• Severe liver dysfunction

promethazine precautions

pediatrics patients

what is the classification for the prototype metoclopramide

dopamine antagonists/prokientic

metoclopramide does what?

Blocks dopamine receptors and makes GI cells more sensitive

to acetylcholine

• Leads to increased GI activity and rapid movement of food

through upper GI tract

what is the classification for the prototype ondansetron

5-HT3 receptor blockers

what is the prototype for the classification 5-HT3 receptor blockers

ondansetron

ondansetron therapeutic actions

Block receptors associated with nausea and

vomiting in the CTZ and locally

ondansetron adverse effects

• CNS effects: headache, dizziness, myalgia

• Pain at injection site, rash, constipation, diarrhea, hypotension, urinary retention

ondansetron contraindications

long QT syndrome

ondansetron cautions

• After abdominal surgery

• Pregnancy and lactation

• Electrolyte abnormalities

ondansetron drug-drug interactions

• Serotonergic medications

• other QT-prolonging medications

ondansetron admin

give the medication

IV slowly (over 15 min) starting 30 min

before chemotherapy administration, and

then 4 and 8 hr later

• give the medication 1 hr

  before anesthesia induction

• give the medication 1 to 2 hr

  before therapy, and then every 8 hr as

  needed

what is the prototype for the classification substance P/neurokinin 1 receptor antagonists

aprepitant

what is the classification for the prototype aprepitant

substance P/neurokinin 1 receptor antagonists

aprepitant therapeutic actions

Act directly in the CNS to block receptors associated with nausea and vomiting

aprepitant adverse effects

Fatigue, diarrhea, dizziness, possible liver damage

aprepitant drug-drug interactions

warfarin, hormonal contraceptives

apreptiant nursing considerations

• Treat headache with non-opioid analgesics.

• Monitor stool pattern.

• Monitor liver function tests periodically.

• Have the client change positions slowly.

• How would you educate clients?