Antiemetics and Their Functions

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Questions and Answers

What is the primary function of antiemetics?

To relieve nausea and vomiting (correct)

To increase appetite

To relieve headaches

To induce sleep

Which of the following describes the role of the Chemoreceptors Trigger Zone (CTZ)?

It regulates body temperature.

It is involved in the sensation of nausea and the action of vomiting. (correct)

It's a pathway that induces appetite.

It triggers the sensation of hunger.

How do most antiemetic drugs primarily exert their effects?

By enhancing gastrointestinal motility

By stimulating the central nervous system

By increasing gastric acid secretion

By blocking pathways that induce vomiting (correct)

Which of the following statements is true regarding the categories of antiemetic drugs?

Antiemetic drugs have different mechanisms of action despite similar outcomes. (D) Signup and view all the answers

Which condition would be least likely to warrant the use of antiemetic drugs?

Severe headache (B) Signup and view all the answers

What is the primary mechanism of action of Metoclopramide?

Blocks dopamine receptors in the CTZ (A) Signup and view all the answers

Which side effect is commonly associated with Meclizine?

Drowsiness (B) Signup and view all the answers

In which scenario is Promethazine contraindicated?

In children under 2 years of age (A) Signup and view all the answers

What classification does Ondansetron belong to?

Serotonin Blocker (C) Signup and view all the answers

How does Scopolamine function as an antiemetic?

By inhibiting cholinergic stimulation (A) Signup and view all the answers

Which mechanism is associated with the action of Meclizine?

Preventing cholinergic stimulation through H1 receptor binding (A) Signup and view all the answers

Which of the following statements about Metoclopramide is incorrect?

It stimulates serotonin receptors to improve motility (A) Signup and view all the answers

Ondansetron's mechanism of action involves blocking which type of receptors?

Serotonin receptors in the GI tract and CTZ (C) Signup and view all the answers

What is the primary action of oxybutynin in the treatment of bladder conditions?

Blocks muscarinic action of acetylcholine to inhibit bladder contractions (D) Signup and view all the answers

Which of the following is NOT a common adverse effect associated with dicyclomine?

Increased appetite (A) Signup and view all the answers

What is the recommended nursing implication when administering oxybutynin?

Ensure adequate fluid intake and assess for urinary retention (D) Signup and view all the answers

What is the main contraindication for prescribing pyridostigmine?

Known drug allergy (D) Signup and view all the answers

What mechanism does dicyclomine employ to alleviate gastrointestinal spasms?

Inhibits muscarinic action of acetylcholine (C) Signup and view all the answers

What type of drug classification does pyridostigmine fall under?

Indirect-Acting Cholinergic Drugs (C) Signup and view all the answers

Which of the following patient education points is most relevant for someone prescribed oxybutynin?

Report any difficulty urinating or severe constipation (B) Signup and view all the answers

What is the recommended route for administering dicyclomine?

Oral administration (A) Signup and view all the answers

What principle ensures that nurses avoid causing harm to patients?

Nonmaleficence (A) Signup and view all the answers

Which of the following best describes the principle of beneficence in nursing?

Promoting well-being and taking actions for the patient's benefit (A) Signup and view all the answers

Which factor is NOT typically included in a cultural assessment of a patient?

Patient’s financial status (A) Signup and view all the answers

In the context of nursing negligence, what does 'causation' refer to?

The direct link between a nurse's breach of duty and patient harm (A) Signup and view all the answers

Which principle emphasizes honesty and truthfulness in nursing practice?

Veracity (B) Signup and view all the answers

What does the principle of autonomy protect in patient care?

Patient's ability to make decisions regarding their medical care (C) Signup and view all the answers

Which scenario would most likely represent a breach of duty in nursing?

Administering medication without confirming the patient's identity (D) Signup and view all the answers

Which of the following reflects the principle of justice in nursing practice?

Providing equal treatment to all patients regardless of background (C) Signup and view all the answers

What is the primary effect of Beta 1 adrenergic agonists on cardiac function?

They increase heart rate and contractility. (C) Signup and view all the answers

Which adrenergic receptor is associated with vasoconstriction when stimulated?

Alpha 1 receptors (D) Signup and view all the answers

What is the mechanism of action for Mirabegron (Myrbetriq)?

Stimulates Beta 3 adrenergic receptors to promote bladder relaxation. (B) Signup and view all the answers

What adverse effect is associated with the use of Tamsulosin (Flomax)?

Abnormal ejaculation (B) Signup and view all the answers

What condition is a contraindication for the use of adrenergic medications?

Hypertension (B) Signup and view all the answers

What is the classification of Sotalol (Betapace)?

Nonselective Beta Blocker (B) Signup and view all the answers

How does Dopamine (Inotropen) primarily affect blood vessels?

Increases renal blood flow via dopaminergic action. (D) Signup and view all the answers

What suffix indicates an adrenergic blocker in drug names?

-olol (A) Signup and view all the answers

What is a significant nursing implication for administering Metoprolol (Lopressor)?

Assess heart rate and blood pressure regularly. (D) Signup and view all the answers

In the context of adrenergic medications, what does 'NASCAR' mnemonic represent for Epinephrine effects?

Nervousness, Angina, Sugar increase, Cardiac arrest, Allergy, Respiratory distress. (A) Signup and view all the answers

Study Notes

Antiemetic and Antinausea Drugs

Antiemetics are medications used to relieve nausea and vomiting (emesis).
Several categories of antiemetic drugs exist, each with different mechanisms of action, though many work by blocking pathways that induce vomiting.
The chemoreceptor trigger zone (CTZ) in the brain is a key area involved in nausea and vomiting.

Metoclopramide (Reglan)

Class: Prokinetic Drug
Routes include oral (PO), parenteral, and requires a prescription.
Indications: Gastroesophageal reflux disease (GERD), delayed gastric emptying, nausea, and vomiting.
Mechanism: Blocks dopamine receptors in the CTZ, desensitizing it to signals from the GI tract. It stimulates GI peristalsis, enhancing stomach emptying.
Contraindications: Seizure disorders, pheochromocytoma, breast cancer, GI obstruction, and allergy to the medication or related compounds (procaine, procainamide).
Adverse Effects: Long-term use can cause irreversible tardive dyskinesia.

Ondansetron (Zofran)

Classification: Serotonin Blocker
Routes include oral (PO) and injectable (IV) forms.
Indications: Nausea and vomiting associated with chemotherapy and post-operative procedures.
Mechanism: Blocks serotonin receptors in the GI tract, CTZ, and vomiting center (VC).
Contraindications: Known allergy and concerns for the development of cleft palate in the first trimester of pregnancy.
Adverse Effects: Known drug allergy and other potential side effects.

Meclizine (Antivert)

Classification: Antihistamine (H1 receptor blocker)
Route: Oral (PO)
Indications: Motion sickness, non-productive cough, allergy symptoms, sedation, and vertigo.
Mechanism: Inhibits acetylcholine (ACh) by binding to H1 receptors, preventing cholinergic stimulation in the vestibular and reticular areas, thereby preventing nausea and vomiting.
Contraindications: Shock and lactation.
Adverse Effects: Drowsiness.

Promethazine (Phenergan)

Classification: Antidopaminergic
Routes: Oral (PO), intramuscular (IM) (preferred), and intravenous (IV) (common).
Indications: Psychotic disorders, intractable hiccups, hay fever symptoms, and allergic conjunctivitis.
Mechanism: Blocks dopamine receptors in the CTZ (CTV).
Contraindications: Children under 2 years old due to risks of fatal respiratory depression.
Adverse Effects: Most common is sedation, but may also result in drowsiness, dry mouth, and lightheadedness.
Nursing Implications: Dilute in at least 10 mL of fluid for administration and administer through a large-bore intravenous (IV) line, avoiding the patient's veins.

Scopolamine (Transderm-Scop, Scopace)

Classification: Anticholinergic (ACh) blocker
Route: 72-hour transdermal patch that releases 1 mg of the medication.
Indications: Nausea and vomiting related to motion sickness and post-operative situations.
Mechanism: Reduces secretions before surgery by binding to and blocking ACh receptors in the inner ear labyrinth and blocks nauseating stimuli to the CTZ and stimuli from the reticular formation to the VC.
Contraindications: Glaucoma, pyloric obstruction, urinary bladder neck obstruction.

Additional Adverse Effects and Nursing Implications

Several medications for nausea and vomiting have potential adverse effects like dizziness, blurred vision, confusion, hallucinations, and urinary retention.
Nursing implications include assessing patient history, current medications, monitoring for contraindications, and educating patients on potential side effects, especially regarding driving or hazardous activities.

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Description

This quiz tests your knowledge on antiemetic drugs, their mechanisms, and related topics. Questions explore the roles of specific drugs like Metoclopramide, Ondansetron, and others, as well as the function of the Chemoreceptors Trigger Zone. Assess your understanding of the pharmacology behind nausea control and the side effects associated with these medications.