Drug Therapy for Nausea and Vomiting - Wolters Kluwer PDF

Chapter 38 Drug Therapy for Nausea and Vomiting  Gastrointestinal (GI) disorders Causes of Nausea oGI tract infection, inflammation and Vomiting Including liver, gallbladder, pancreas (N/V) #1 oImpaired GI motility...

Chapter 38 Drug Therapy for Nausea and Vomiting  Gastrointestinal (GI) disorders Causes of Nausea oGI tract infection, inflammation and Vomiting Including liver, gallbladder, pancreas (N/V) #1 oImpaired GI motility oImpaired GI muscle tone oOvereating or ingestion of foods or fluids that irritate GI mucosa Copyright © 2025 Wolters Kluwer. All rights reserved. 2  Cardiovascular disorders Causes of Nausea Infectious disorders and Vomiting Neurologic disorders (N/V) #2 Metabolic disorders Drug therapy oMost common adverse effect of drug therapy Copyright © 2025 Wolters Kluwer. All rights reserved. 3  Noxious stimuli (including pain; unpleasant Causes of Nausea sights, odors) and Vomiting Emotional disturbances, physical or mental (N/V) #3 stress Radiation therapy Motion sickness Postoperative status (pain, drugs, impaired GI motility) Pregnancy Migraines Copyright © 2025 Wolters Kluwer. All rights reserved. 4  Medications used to prevent/treat nausea and Antiemetics vomiting oNausea: unpleasant sensation of abdominal discomfort accompanied by a desire to vomit oVomiting: expulsion of stomach contents through the mouth Copyright © 2025 Wolters Kluwer. All rights reserved. 5  In pregnancy: activation of chemoreceptor Physiology of trigger zone (CTZ) plays a role. Nausea and In motion sickness: inner ear receptors are Vomiting stimulated. Vomiting occurs when vomiting center (in medulla oblongata) is stimulated. oSignals provided by the CTZ, cerebral cortex, sensory organs, vestibular apparatus Copyright © 2025 Wolters Kluwer. All rights reserved. 6  Is the following statement True or False? Question #1 Nausea and vomiting are the most common adverse effects of medication. Copyright © 2025 Wolters Kluwer. All rights reserved. 7  True Answer to Question #1 Rationale: Nausea and vomiting are the most common adverse effects of medication. Copyright © 2025 Wolters Kluwer. All rights reserved. 8  Phenothiazines (prototype: promethazine) are Phenothiazines central nervous system (CNS) depressants that are used for a variety of reasons, including the prevention and treatment of nausea and vomiting. With promethazine, common side effects include blurred vision, urinary retention, dry mouth, photosensitivity, drowsiness, and confusion. Additionally, orthostatic hypotension and exacerbation of asthma, and alteration of the Q wave and T wave can occur. Copyright © 2025 Wolters Kluwer. All rights reserved. 9  Antihistamines (prototype: hydroxyzine) are Antihistamines used primarily to prevent histamine from exerting its widespread effects on body tissues. Antihistamines used as antiemetic agents are the “classic” antihistamines or H1 receptor blocking agents (as differentiated from cimetidine and related drugs, which are H2 receptor blocking agents). With hydroxyzine, adverse anticholinergic effects include drowsiness, dizziness, confusion, dry mouth, thickened respiratory secretions, blurred vision, urinary retention, and tachycardia and possible prolonged QT interval and torsades de pointes. Copyright © 2025 Wolters Kluwer. All rights reserved. 10  The 5-HT3 receptor antagonists (prototype: 5-HT3 Receptor ondansetron) are the cornerstones of therapy Antagonists for control of acute emesis caused by chemotherapy agents with moderate to high emetogenic potential. Usually considered drugs of first choice for postoperative nausea and vomiting. Adverse effects of ondansetron are usually mild to moderate. Common ones include diarrhea, headache, dizziness, constipation, fatigue, transient elevation of liver enzymes, and pain at the injection site. Copyright © 2025 Wolters Kluwer. All rights reserved. 11  Substance P is a peptide neurotransmitter in Substance the neurokinin family (prototype: aprepitant). P/Neurokinin 1 It plays a role in mediating acute Antagonists chemotherapy-induced nausea and vomiting (along with serotonin) and is believed to be the primary mediator of delayed nausea and vomiting associated with chemotherapy. Aprepitant is well tolerated, with the most common adverse effects being fatigue, weakness, dizziness, abnormal heart rhythm, headache, and hiccups. Infusion site pain has been reported with IV administration. Copyright © 2025 Wolters Kluwer. All rights reserved. 12  Nonpharmacologic techniques have become Nonpharmacologi an acceptable adjunct to antiemetic drug c Techniques therapy. The use of herbal supplements has also received support. Techniques include: oAcupuncture and acupressure oHerbal supplements Copyright © 2025 Wolters Kluwer. All rights reserved. 13  Identify risk factors for nausea and vomiting Assessment (e.g., digestive or other disorders in which nausea and vomiting are symptoms; drugs associated with nausea and vomiting). Interview regarding frequency, duration, and precipitating causes of nausea and vomiting. Also, question the patient about accompanying signs and symptoms, characteristics of vomitus (amount, color, odor, presence of abnormal components, such as blood), and any measures that relieve nausea and vomiting. When possible, observe and measure the vomitus. Copyright © 2025 Wolters Kluwer. All rights reserved. 14  Use measures to prevent or minimize nausea Nursing and vomiting. Interventions #1 Assist patients to identify situations that cause or aggravate nausea and vomiting. Avoid exposure to stimuli when feasible (e.g., unpleasant sights and odors; excessive ingestion of food, alcohol, or nonsteroidal anti- inflammatory drugs). Administer analgesics before painful diagnostic tests and dressing changes or other therapeutic measures may be helpful, as pain may cause nausea and vomiting. Copyright © 2025 Wolters Kluwer. All rights reserved. 15  Administer antiemetic drugs 30 to 60 minutes Nursing before a nausea-producing event, when Interventions #2 possible (e.g., radiation therapy, cancer chemotherapy, travel). Adjust the timing of any oral drugs that cause gastric irritation, nausea, and vomiting by taking with or just after food. For any drug likely to cause nausea and vomiting, check reference sources to determine whether it can be given with food without altering beneficial effects. Copyright © 2025 Wolters Kluwer. All rights reserved. 16  Assess the patient’s condition and report to Nursing the health care provider if nausea and Interventions #3 vomiting occur. In some instances, a drug (e.g., digoxin, an antibiotic) may need to be discontinued or reduced in dosage. In other instances (e.g., paralytic ileus, GI obstruction), preferred treatment is restriction of oral intake and nasogastric intubation. Suggest that a female patient eat dry crackers before rising in the morning and ingestion of small frequent protein meals to help prevent nausea and vomiting associated with pregnancy. Copyright © 2025 Wolters Kluwer. All rights reserved. 17  Avoid administering oral intake of food, fluids, Nursing and drugs during acute episodes of nausea Interventions #4 and vomiting. Oral intake may increase vomiting and risks of fluid and electrolyte imbalances. Minimize activity during acute episodes of nausea and vomiting. Lying down and resting quietly are often helpful. Copyright © 2025 Wolters Kluwer. All rights reserved. 18  Give supportive care during vomiting Nursing episodes. Interventions #5 Give replacement fluids and electrolytes. Offer small amounts of food and fluids orally when tolerated and according to patient preference. Record vital signs, intake and output, and body weight at regular intervals if nausea or vomiting occurs frequently. Decrease environmental stimuli when possible (e.g., noise, odors). Allow the patient to lie quietly in bed when nauseated. Decreasing motion may decrease stimulation of the vomiting center in the brain. Copyright © 2025 Wolters Kluwer. All rights reserved. 19  Help the patient rinse his or her mouth after Nursing vomiting. Rinsing decreases the bad taste and Interventions #6 corrosion of tooth enamel caused by gastric acid. Provide requested home remedies when possible (e.g., a cool, wet washcloth to the face and neck). Provide appropriate education for any drug therapy. Copyright © 2025 Wolters Kluwer. All rights reserved. 20