DOC PREVIEW
U of A NURS 3313 - Antiemetic and Antinausea Drugs

This preview shows page 1-2 out of 5 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 5 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 5 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 5 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

Antiemetic and Antinausea DrugsDefinitions- Nausea – Unpleasant feeling that often precedes vomiting- Emesis (vomiting) – Forcible emptying of gastric, and occasionally, intestinal contents- Antiemetic drugs – Used to relieve nausea and vomitingo Food intolerance o Motion sickness o Drugs o Surgery o Pregnancy o Poisoningo Cancer therapy Vomiting Center and Chemoreceptor Trigger Zone- Vomiting center (VC)- Chemoreceptor trigger zone (CTZ)o Both located in the braino Once stimulated, cause the vomiting reflexAntiemetics and Antinausea Drugs- Anticholinergic drugs – Blocking receptor sites- Antihistamines (histamine 1 [H1] receptor blockers) – Act as a sedative - Antidopaminergic drugs – Blocking receptor site- Prokinetic drugs – Only intended to slow motility of GI tract- Serotonin blockers – Blocking receptor site- Tetrahydrocannabinoids – Medical marijuana - Mechanism of Actiono Many different mechanisms of actiono Most work by blocking one of the vomiting pathways, thus blocking the stimulus that induces vomiting- Indicationso Specific indications vary per class of antiemeticso General use for each type: prevention and reduction of nausea and vomiting Pre-medicate- Mechanism of Action and Other Indicationso Anticholinergic drugs (ACh blockers) Bind to and block acetylcholine (ACh) receptors in the inner ear labyrinth Block transmission of nauseating stimuli to CTZ  Also block transmission of nauseating stimuli from the reticular formation to the VC scopolamine (Transderm-Scōp, Scopace) - Used to be used in L&D- Can cause euphoria - Causes drying of the mouth  Used for flying, boating – motion sicknesso Antihistamine drugs (H1 receptor blockers) Inhibit ACh by binding to H1 receptors Prevent cholinergic stimulation in vestibular and reticular areas, thus preventing nausea and vomiting Also used for motion sickness, nonproductive cough, allergy symptoms, sedation Helps because it is a sedative  Examples- dimenhydrinate (Dramamine)- Diphenhydramine (Benadryl)- meclizine (Antivert)o Does not make patient sleepy o Antidopaminergic drugs Block dopamine receptors in the CTZ Reduce the likelihood of nausea and vomiting  Also used for psychotic disorders, intractable hiccups Examples: prochlorperazine (Compazine)and promethazine (Phenergan)o Prokinetic drugs Block dopamine receptors in the CTZ Cause CTZ to be desensitized to impulses it receives from the GI tract Also stimulate peristalsis in GI tract, enhancing emptying of stomach contents Also used for gastroesophageal reflux disease (GERD), delayed gastric emptying metoclopramide (*Reglan)- Long-term use may cause irreversible tardive dyskinesia – very rare - Enhances GI motility - Used as a de-sensitizer, numbs- Delays gastric emptying - GERD- Feeding (PEG) tubes o Serotonin blockers Block serotonin receptors in the GI tract, CTZ, and VC Used for nausea and vomiting in patients receiving chemotherapy and for postoperative nausea and vomiting Examples- dolasetron (Anzemet)- granisetron (Kytril)- ondansetron (Zofran) – Created for chemotherapy patients - palonosetron (Aloxi) – Cheaper and created for chemotherapy patients o Tetrahydrocannabinoids Major psychoactive substance in marijuana Inhibitory effects on reticular formation, thalamus, cerebral cortex Alter mood and body’s perception of its surroundings, which may help relieve nausea and vomitingo Tetrahydrocannabinoids (THC) (cont’d) dronabinol (Marinol) Used for nausea and vomiting associated with chemotherapy, and anorexia associated with weight loss in AIDS patientsMiscellaneous Antinausea Drugs- phosphorated carbohydrate solution (Emetrol)o Mint-flavored oral solutiono Used off label for treatment of morning sicknesso Adverse Effectso Vary according to drug usedo Stem from their nonselective blockade of various receptorso Phenergan – not given to children because can cause nervous system effects Don’t want to use long term Herbal Products: Ginger- Used for nausea and vomiting, including that caused by chemotherapy, morning sickness, and motion sickness- Adverse effectso Anorexia, nausea and vomiting, skin reactions- Drug interactionso May increase absorption of oral medicationso Increase bleeding risk with anticoagulantsNursing Implications- Assess complete nausea and vomiting history, including precipitating factors- Assess current medications- Assess for contraindications and potential drug interactions- Many of these drugs cause severe drowsiness; warn patients about driving or performing any hazardous tasks- Taking antiemetics with alcohol may cause severe CNS depressiono With all of them- Teach patients to change positions slowly to avoid hypotensive effectso Except Zofran and Aloxi - For chemotherapy, antiemetics are often given 30 to 60 minutes before chemotherapy begins- Monitor for therapeutic effects- Monitor for adverse effectsQuestions1. The nurse is preparing to administer scopolamine to a patient. It is most important for the nurse to determine if the patient has a history of which condition?A. CataractsB. Narrow-angle glaucoma C. PresbyopiaD. Detached retinaRationale: The nurse should only administer the anticholinergic drug scopolamine after careful assessment of the patient’s health history and medication history. One very important concern to reemphasize with scopolamine, which is commonly administered in patch form to prevent motion sickness, is the contraindication to its use in patients with narrow-angle glaucoma. If the patient has a history of this disorder, then another antiemetic or antinausea drug should be used. 2. A patient is receiving a continuous tube feeding via a PEG tube. Which drug would most likely be prescribed for this patient? A. metoclopramide (Reglan)B. meclizine (Antivert)C. aprepitant (Emend)D. phosphorated carbohydrate solution (Emetrol)Rationale: Metoclopramide is a prokinetic drug that promotes the movement of substances through the gastrointestinal tract and increases gastrointestinal motility. This action is helpful in preventing aspiration in those receiving tube feedings.3. A patient 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 toA. prevent recurrence of the chemotherapy-induced nausea and vomiting.B. prevent stress ulcers.C. improve his mood.D. stimulate


View Full Document

U of A NURS 3313 - Antiemetic and Antinausea Drugs

Download Antiemetic and Antinausea Drugs
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Antiemetic and Antinausea Drugs and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Antiemetic and Antinausea Drugs 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?