Term
| Antiemetics and Antinausea Drugs MOA |
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Definition
1. many different moas
2. most work by blocking one of the vomiting pathways, thus blocking the stimulus that induces vomiting |
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Term
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Definition
1. specific indications vary per class
2. general use for each type: prevention and reduction of nausea and vomiting |
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Term
MOAs and Indications
Anticholinergic drugs (ACh blockers) |
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Definition
1. bind to and block acetycholine (ACh) receptors in the inner ear labyrinth
2. block transmission of nauseating stimuli to CTZ
3. also block transmission of nauseating stimuli from the reticular formation to the VC
4. scopolamine (Transderm-Scop, Scopace) |
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Term
| The nurse is preparing to administer scopolamine to a patient. It is important for the nurse to determine if the patient has a history of which condition? |
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Definition
Narrow-angle glaucoma
Rationale: The nurse should only adminster the anticholnergic drug scopolamine after careful assessment of the pt's health history and med history. One very important concern to re-emphasize with scopolamine, which is commonly adminstered in patch form to prevent motion sickness, is the contraindication to its use in pts with narrow-angle glaucoma. If the pt has a history of this disorder, then another antiemetic or antinausea drug should be used. |
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Term
MOAs and Indications
Antihistamine drugs (H1 receptor blockers) |
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Definition
1. inhibit ACh by binding to H1 receptors
2. prevent cholinergic stimulation in vestibular and reticular areas, thus preventing nausea and vomiting
3. also used for motion sickness, nonproductive cough, allergy symptoms, sedation
4. examples: dimenhydrinate (Dramamine) ; diphenhydramine (Benadryl); meclizine (Antivert) |
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Term
MOAs and Indications
Antidopaminergic drugs |
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Definition
1. block dopamine receptors in the CTZ
2. also used for psychotic disorders, intractable hiccups
3. examples: prochlorperazine (Compazine); promethazine (Phenergan); droperidol: use is controversial because of associated cardiac dysrhythmia |
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Term
MOAs and Indications
Prokinetic drugs |
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Definition
1. block dopamine receptors n the CTZ
2. cause CTZ to be desensitized to impulses it receives from the GI tract
3. also stimulate peristalsis in the GI tract, enhancing emptying of stomach contents
4. also used for gastroesophageal reflux disease (GERD), delayed gastric emptying
5. metoclopramide (REglan) - long term use may cause irreversible tardive dyskinesia |
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Term
| A pt is receiving a continuous tube feeding via a PEG tube. Which drug would most likely be prescribed for this pt? |
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Definition
metoclopramide (Reglan)
Metoclopramide is a prokinetic drug that promotes the movement of substances through the GI tract and increases GI motility. This action helps prevent aspiration in those receiving tube feedings. |
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Term
MOAs and Indications
Serotonin blockers |
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Definition
1. block serotonin receptors in the GI tract, CTZ, and VC
2. used for nausea and vomiting in pts receiving chemotherapy and for postoperative nausea and vomiting
3. examples: dolasetron (Anzemet); granisetron (Kytril); ondansetron (Zofran); palonosetron (Aloxi) |
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Term
MOAs and Indications
Tetrahydrocannabinoids |
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Definition
1. major psychoactive substance in marijuana
2. inhibitory effects on reticular formation, thalamus, cerebral cortex
3. alter mood and body's perception of its surroundings, which may help relieve nausea and vomiting |
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Term
| A pt with terminal cancer has not had chemotherapy for a few weeks and has had no nausea or vomiting since then. However, he is taking dronabinol twice a day. The reason for the dronabinol order is to |
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Definition
stimulate his appetite
Dronabinol is used as an appetite stimulant in pts who are experiencing nutritional wasting due to cancer and cancer treatment |
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Term
Tetrahydrocannabinoids (THC) cont.
Indications |
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Definition
1. dronabinol (Marinol)
2. used for nausea and vomiting associated with chemotherapy and anorexia associated with weight loss in AIDS patients |
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Term
| A pt is 2 months pregnant. She comes to the clinic complaining of severe morning sickness. She has tried numerous non-pharmacologic measures to relieve the morning sickness, but they have not worked. The nurse anticipates the use of which antinausea drug? |
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Definition
phophorated carbohydrate solution (Emetrol)
Emetrol is a mint-flavored, pleasant tasting oral solution used to relieve nausea. It works by direct local action on the walls of the GI tract, where it reduces cramping caused by excessive smooth muscle contraction. It can be used to control mild cases of nausea and vomiting. It does not have a pregnancy category rating, but one of its listed unlabeled (non-FDA approved) uses is for treatment of morning sickness. |
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Term
| Miscellaneous Antinausea Drugs |
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Definition
1. phosphorated carbohydrate solution (Emetrol)
a. mint flavored oral solution
b. used off label for treatment of morning sickness
2. aprepitant (Emend)
a. used for prevention of nausea and vomiting associated with highly emetogenic cancer chemotherapy regimens |
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Term
| Which group of drugs used to treat nausea does the nurse identify as most likely to cause a prolonged QTc interval? |
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Definition
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Term
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Definition
1. used for nausea and vomiting, including that caused by chemotherapy, morning sickness, and motion sickness
2. adverse effects - anorexia, nausea and vomiting, skin reactions
3. drug interactions - may increase absorption of oral meds; increased bleeding risk with anticoagulants |
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Term
| A pt tells the nurse that he takes ginger almost every day for nausea. It is important for the nurse to determine if the pt is taking which medication? |
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Definition
warfarin
use of ginger can increase absorption of all oral meds and may theoretically increase bleeding risk with anticoagulants or antiplatelet drugs (warfarin or clopidogrel) |
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Term
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Definition
1. assess complete nausea and vomiting history, including precipitating factors
2. assess current meds
3. assess for contraindication and pot drug interactions
4. many of these drugs cause severe drowsiness; warn pts about driving or performing any hazardous tasks
5. taking antiemetics with alcohol may cause severe CNS depression
6. teach pts to change positions slowly to avoid hypotensive effects
7. for chemotherapy, antiemetics are often given 30 to 60 minute before chemotherapy begins
8. monitor therapeutic effects
9. monitor for adverse effects |
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Term
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Definition
1. antihistamine
2. commonly used to treat dizziness, vertigo, and nausea and vomiting associated with motin sickness
2. contraindicated in shock and lactation
3. oral use only |
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Term
| prochlorperazine (Compazine) |
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Definition
1. antidopaminergics
2. frequently used in hospital setting - esp. in injectable form
3. contraindicated in pts with hypersensitivity to phenothiazines, those in a coma, and those who have seizures, encephalopathy or bone marrow suppression
4. both oral and injectable |
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Term
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Definition
1. prokinetic
2. only by prescription
3. severe adverse effects if not used correctly
4. used for treatment of delayed gastric emptying and gastroesophageal reflux and is also an antiemetic
5. contraindicated in pts with sezure disorder, pheochromocytoma, breast cancer, or GI obstruction and also in pts with a hypersensitivity to it or to procaine or procainamide.
6. available in both oral and parenteral formulations
7. extrapyramidal adverse effects can occur with its use, esp. in young adults
8. potential for developing tardive dyskinesia with long term use |
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Term
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Definition
1. serotonin blocker
2. approved in 1992, breakthrough in treatment of chemotherapy induced vomiting
3. also used for treatment of hyperemesis gravidarum (nausea and vomiting assoc. with pregnancy
4. avail in both oral and injectable forms
5. no contraindications except with allergy to it |
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Term
| Antidopinergic drugs also treat (besides nausea and vomiting) |
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Definition
| anxiety, intractable hiccups, schizophrenia, mania |
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Term
| Administer 50 mg Benadryl intravenously |
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Definition
| undiluted over 2 min (25 mg/min) |
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Term
| This drug works by blocking serotonin in GI tract, vomiting center, and chemoreceptor trigger zone (CTZ) |
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Definition
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Term
| Metoclopramide (Reglan) is useful in treating postoperative nausea and vomiting because it |
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Definition
| promotes motility in small intestine |
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Term
| When planning to administer metoclopramide (Reglan) give |
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Definition
| 30 minutes before meals and at bedtime |
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