Chapter 52: Antiemetic and antinausea drugs

Which statement regarding antiemetic medications, if made by the patient, indicates the need for further patient teaching?

"I will apply the scopolamine patches to rotating sites on my arms." Transdermal scopolamine patches should be applied to nonirritated areas behind the ear, not on the arms.

The primary health care provider prescribes metoclopramide to a patient for the treatment of nausea and vomiting. What will the nurse advise the patient when administering this drug?

"You should avoid long-term use of this medication." The nurse suggests the patient avoid long-term use of metoclopramide because it causes tardive dyskinesia, an involuntary neurologic movement.

The primary health care provider prescribes diphenhydramine to a patient who has nausea and vomiting. What advice will the nurse give to the patient while administering this drug?

"You should not consume alcohol." The nurse suggests that the patient avoid drinking alcohol because alcohol is a central nervous system depressant, and patients taking diphenhydramine may experience an exacerbation of central nervous system depression.

The primary health care provider prescribes aprepitant to a pregnant patient to treat nausea and vomiting. After assessment, the nurse finds that the patient is taking warfarin. What will the nurse assess from the laboratory test reports in this situation?

Clotting time of blood The nurse should assess clotting time from the laboratory test reports, based on which the international normalized ratio (INR) is established. In this situation, aprepitant interacts with warfarin and increases the clotting time of blood.

When planning administration of antiemetic medications to a patient, the nurse is aware that combination therapy is preferred for what reason?

Different vomiting pathways are blocked. Combining antiemetic drugs from various categories allows the blocking of the vomiting center and chemoreceptor trigger zone through different pathways (GI, inner ear, cerebral cortex) thus enhancing the antiemetic effect.

The nurse is caring for an older adult who has nausea and vomiting and has been prescribed diphenhydramine. How will the nurse administer this medication to the patient?

In a single dose at a rate of 25 mg/min Diphenhydramine should be administered via the intravenous route at a rate of 25 mg/min.

Which adverse condition is most likely to be found in a patient taking scopolamine for the last 2 weeks?

Increased intraocular pressure Scopolamine is an anticholinergic medication that inhibits the binding of acetylcholine (ACh) with cholinergic receptors. It causes an imbalance of ACh and norepinephrine and increases the lachrymal secretions, resulting in increased intraocular pressure. Therefore scopolamine is contraindicated in a patient with narrow-angle glaucoma.

The nurse assesses a hospitalized patient who has nausea and vomiting who has been prescribed promethazine. What side effect might the nurse expect in this patient?

Increased risk of low blood pressure The patient who has been prescribed promethazine may have an increased risk of low blood pressure because of the adverse effect of orthostatic hypotension.

The nurse is caring for a patient who has cancer and exhibits symptoms of nausea and vomiting. The patient has been prescribed radiation therapy and metoclopramide. What is the most appropriate nursing action in this situation?

Instruct the patient to avoid taking anticholinergics and opiates. The nurse should instruct the patient to avoid taking anticholinergics and opiates because the action of metoclopramide will be decreased when it is taken along with those drugs.

Which drug can cause tardive dyskinesia as an adverse effect?

Metoclopramide

The primary health care provider prescribes scopolamine to a patient who has motion sickness. Which conditions will cause concern for this patient?

Narrow-angle glaucoma The nurse has to assess the patient's medical history for narrow-angle glaucoma because the drug is contraindicated in this situation.

The nurse is caring for a patient who has cancer and has been prescribed dronabinol twice a day. Which laboratory test will the nurse expect the patient to undergo to facilitate further evaluation?

Urinalysis with specific gravity A patient with cancer who has been prescribed dronabinol twice a day may experience low urine output. The drug prevents the recurrence of chemotherapy-induced nausea and vomiting. The nurse may evaluate urinalysis with a specific gravity laboratory test report to check the frequency of urine output.

What are the clinical uses of meclizine? Select all that apply.

Vertigo and motion sickness. The antihistaminic drug meclizine is used in the treatment of vertigo and motion sickness.

The nurse is caring for a patient with cancer who experiences severe nausea and vomiting. The patient has been prescribed a high-dose regimen of cisplatin. The primary health care provider prescribes which antiemetic drug for this patient?

Aprepitant Cisplatin is a highly emetogenic anticancer drug. The primary health care provider may prescribe aprepitant because it has high antiemetogenic activity due to direct selective blockade of neurokinin 1 receptors in the brain.

The primary health care provider prescribes dronabinol as a second-line antiemetic drug for the treatment of nausea and vomiting associated with chemotherapy in a patient who has cancer. Which action will the nurse perform before administering the medication to the patient?

Assess motor and cognitive abilities Dronabinol is administered as second-line antiemetic drug for the treatment of nausea and vomiting associated with chemotherapy when other antiemetics have failed to work. The nurse has to assess motor and cognitive abilities before administration because of the drug's inhibitory action on the thalamus and cerebral cortex in the brain.

Medication "X" is effective in patients who have cancer and experience nausea and vomiting associated with chemotherapy. During postmarketing surveillance, the drug is found to produce ventricular dysrhythmias. What recommendations do the U.S. Food and Drug Administration (FDA) make for such a medication?

Avoid prescribing for patients who have been prescribed chemotherapy. Some drugs may be effective in the initial stages of treatment. However, they cause some adverse effects such as ventricular dysrhythmias if they are administered over the long term. According to the FDA, such medications cannot be prescribed for the treatment of nausea and vomiting associated with chemotherapy.

The nurse is caring for a patient who has severe nausea and vomiting caused by food poisoning. The patient is prescribed antiemetic medications as a combination therapy. Of what will the nurse be aware while administering the medications?

Combination therapy blocks various vomiting pathways. The nurse must be aware of combination therapy with administration of antiemetic drugs because they can increase the effectiveness of these drugs by blocking various vomiting pathways.

Which conditions might the patient with dehydration experience? Select all that apply.

Dizziness, dry mouth Dehydration is caused by the loss of water from the body, which leads to dry mouth, dizziness, and decrease in urinary output.

The nurse is caring for a patient diagnosed with cancer who experiences nausea and vomiting and who is prescribed ondansetron. After administering the medication, the nurse finds that the symptoms persist. What medication will the primary health care provider prescribe for the patient with this condition?

Dronabinol Dronabinol is prescribed for patients with cancer because it has been approved by the U.S. Food and Drug Administration as a second-line drug to treat nausea and vomiting related to chemotherapy when treatment with other antiemetics has failed

A patient receiving an anticholinergic drug to treat nausea and vomiting should be taught to expect which adverse effect?

Dry mouth Anticholinergic drugs block the parasympathetic nervous system, which causes the body to "rest and digest." Blocking of these effects leads to constipation, urinary retention, and decreased secretions (dry mouth).

Before administering the anticholinergic drug scopolamine, the nurse would be careful to assess the patient for a history of which condition?

Glaucoma Anticholinergic drugs are contraindicated in patients with glaucoma. These drugs can cause pupillary dilation, which can obstruct the flow of aqueous humor and increase intraocular pressure.

The nurse is caring for a patient who has been prescribed metoclopramide for the treatment of postoperative nausea and vomiting. What is the action of this drug?

It increases motility in the small intestine. Metoclopramide acts by increasing motility in the small intestine, thus minimizing gastric distension.

A patient has nausea and vomiting associated with motion sickness. The patient is prescribed meclizine. Which statement is true about contraindications of this drug?

It is contraindicated in lactating patients. Meclizine is contraindicated in lactating patients because it passes into the breast milk and can sedate the newborn.

Which nursing intervention helps prevent complications in a patient who is scheduled for a tonsillectomy and has been prescribed metoclopramide?

Monitoring the patient's blood pressure Metoclopramide is a prokinetic that acts as a dopamine antagonist and helps prevent postoperative nausea and vomiting. Metoclopramide decreases dopamine levels and causes hypotension. Therefore the nurse should monitor the patient's blood pressure to prevent complications from the adverse effects of the medication.

The nurse is caring for a patient who has been prescribed scopolamine for motion sickness. Which site is appropriate for application of the patch?

On a hairless area behind the ear The scopolamine transdermal patch should be applied on an area of intact skin on the head behind the ear after cleaning and drying the area to reduce secretions. The patch may be dislodged if applied to irritated skin, the shoulder, or the chest.

A patient who is receiving chemotherapy has developed nausea and vomiting. Which drug will the nurse expect to be added to the treatment plan along with the chemotherapeutic agent?

Ondansetron Ondansetron blocks serotonin receptors in the gastrointestinal tract, chemoreceptor trigger zone (CTZ), and vomiting center of the brain, thereby preventing chemotherapy-associated nausea and vomiting.

Which drug works by blocking serotonin in the gastrointestinal tract, vomiting center, and chemoreceptor trigger zone?

Ondansetron Ondansetron is a serotonin blocker.

The nurse is caring for a patient who is 2 months pregnant and is experiencing morning sickness. Which antinausea drug would the nurse expect to be prescribed for the patient?

Ondansetron The patient should be administered ondansetron to relieve nausea associated with morning sickness during pregnancy.

Which medication can be prescribed for the treatment of hyperemesis gravidarum?

Ondansetron Vomiting and nausea during pregnancy is called hyperemesis gravidarum. Ondansetron is a serotonin blocker that blocks serotonin receptors in the vomiting center in the medulla and prevents emesis. It is prescribed for the treatment of hyperemesis gravidarum.

The primary health care provider prescribes aprepitant to a patient for the treatment of nausea and vomiting. Which drugs will the nurse expect to be added to the treatment plan to enhance the antiemetic effect? Select all that apply.

Ondansetron, Dexamethasone, and Methylprednisolone. Ondansetron can be added to the treatment plan, because it augments the antiemetic effect of aprepitant. Dexamethasone and methylprednisolone are corticosteroids, which interact with aprepitant and increase its bioavailability, so they can be added.

The nurse recognizes that metoclopramide is useful in treating postoperative nausea and vomiting due to which effect?

Promotes motility in the small intestine Metoclopramide works by increasing gastrointestinal motility in the small intestine, thus minimizing gastric distention and accompanying stimulation of the vomiting center.

The nurse would expect to teach a patient about which anticholinergic commonly used to prevent motion sickness?

Scopolamine Scopolamine blocks the binding of acetylcholine with cholinergic receptors in the inner ear, an imbalance of which is a common cause of motion sickness.

A patient reports having nausea and vomiting associated with motion sickness. Which antiemetic commonly used to prevent motion sickness will the nurse expect the primary health care provider to prescribe?

Scopolamine Scopolamine specifically blocks the binding of acetylcholine with cholinergic receptors in the inner ear, an imbalance of which is a common cause of motion sickness.

Which class of drugs is used along with commonly prescribed antiemetics to prevent nausea and vomiting associated with chemotherapy? Select all that apply.

Serotonin blockers, Tetrahydrocannabinoids, and Phosphorated carbohydrate solutions.

The nurse is caring for an older adult who is prescribed meclizine. The nurse finds that the patient's mouth is dry. What may the primary care provider order to alleviate this symptom?

Sugarless candy and gum Sugarless candy and gum may help with the production of saliva and alleviate the elderly patient's discomfort.

The nurse is caring for a patient who has nausea and vomiting who has been prescribed promethazine. Which is the most appropriate assessment before administering this medication?

The patient's vital signs The adverse effects of promethazine are orthostatic hypotension and tachycardia. Therefore to prevent these adverse effects, the nurse should assess vital signs such as blood pressure and pulse rate.

When planning to administer metoclopramide, the nurse is aware that this drug is most effective when given at what time?

Thirty minutes before meals and at bedtime Metoclopramide should be administered 30 minutes before meals and at bedtime. Administering the medication before meals allows time for onset to increase gastrointestinal motility before food ingestion, thus decreasing stomach distention and the resulting nausea and vomiting

Before administering promethazine to a patient who has nausea and vomiting, the nurse examines the patient's skin turgor before administering the drug. Why does the nurse perform this assessment?

To assess for the signs and symptoms of dehydration Antidopaminergic drugs such as promethazine are to be used only after cautious assessment for signs and symptoms of dehydration and electrolyte imbalance by evaluating skin turgor

Besides treating nausea and vomiting, what are the uses of antidopaminergic drugs? Select all that apply.

Treating anxiety, treating schizophrenia, and treating intractable hiccups. Antidopaminergic drugs also are used in the treatment of psychotic disorders such as anxiety and schizophrenia, as well as intractable hiccups and nausea and vomiting

The nurse is caring for a patient who has nausea and vomiting and has been prescribed promethazine in suppository form. How will the nurse administer this medication?

Via the rectal route The nurse administers the medication promethazine via the rectal route because it is prescribed in suppository form.