N5375 Lesson 8B GI.pptx

Week 8B: Gastrointestinal N5375: Pharmacology Columbia University School of Nursing Dr. Ana Maria Kelly Summer 2024 1  Chapters Chapter 81: Drugs for Peptic Ulcer Disease Chapter 82: Laxatives Chapter 83: 2  GI Study Questions 1. Connect Lesson 8A and 8B, wh...

Week 8B: Gastrointestinal N5375: Pharmacology Columbia University School of Nursing Dr. Ana Maria Kelly Summer 2024 1  Chapters Chapter 81: Drugs for Peptic Ulcer Disease Chapter 82: Laxatives Chapter 83: 2  GI Study Questions 1. Connect Lesson 8A and 8B, which med group from lesson 8A increases risk of PUD? 2. 5 classes of treatment for PUD, which tend to overlap with GERD? 3. Suffix for H2 blockers + MOA, use, SE, any education? 4. Suffix for PPIs + MOA, use, SE, any education? 5. Name 3 types of antacids, which one causes diarrhea and which one more likely to cause constipation? 6. Explain order of laxative use and how each class works 7. Why don’t we use stimulant laxatives regularly is dealing with chronic constipation? 8. Provide nursing education for loperamide: consider dosing and precaution. 9. Three antiemetics to know: ondansetron, metoclopramide and promethazine. Especially note the most dangerous SE of each. 10.Know other meds from previous lessons that can also help with nausea 11.Note connection to Beers list and antispasmodic 3 Drugs for Peptic Ulcer Disease Chapter 81 4 What do we mean by PUD? Peptic Ulcer Disease = upper GI disorder characterized by varying degree of erosion to gut wall (often ulcers are broken up into gastric or duodenal) Caused by triggering factor + reduced defenses Triggering factors: H. pylori infection, NSAID use (like aspirin), smoking, increased acid or pepsin (enzyme) production Reduction of defenses in gut: damaged mucosal layer, reduced bicarbonate (neutralizes acid), and reduced prostaglandins How is it related to Gastroesophageal reflux disease (GERD)? They are separate conditions, but have similarity of too much acid causing discomfort & similarity of treatment trying to stop or neutralize acid production Estimated 20% US has GERD, up 6% has PUD 5 Treatment for PUD 1. Eradicate H. pylori with antibiotics 1. Antibiotics to treat H. pylori (Usually 2) 2. Antisecretory agents A. H2 receptor antagonists –tidines 2. Reduce gastric B. Proton pump inhibitors (PPI) –prazoles acidity with H2 3. Mucosal protectants block, PPI or 1. Sucalfrate antacids 2. Bismuth subsalicylate [Pepto-Bismol] 4. Antacids A. Calcium carbonate 3. Enhance mucosal B. Magnesium hydroxide defenses with C. Aluminum hydroxide sucralfate or Pepto 6  New med Talicia since 2019 contains 2 antibiotics (rifabutin and amoxicillin) + omeprazole in a single capsule that a Additiona new PUD patient would take for 14 days and then re-evaluate l Notes 4 pills, 3x/daily Traditionally, patient will have to on continue with 8-week PPI trial, take PPI like omeprazole 1x/day, 30-60 min Treatmen before meal Any PPI will work, most OTC now t for PUD Always looking for “lowest effective dose” Only some people would stay on PPI for life (more severe damage to esophagus) 7  What about GERD? Often self-treat Main symptom is heartburn (for PUD it was ”burning” stomach pain) Most people will start with antacids like calcium carbonate [Tums] symptomatically as needed Could go for more effective aluminum hydroxide/magnesium hydroxide antacid [Mylanta] If symptoms are persistent, 2x/week, could consider H2 blockers If not sufficient, can move to PPI, but best not to stay on this long term (OK to take PPI and H2-block together, space out dosing) Note: H. pylori not indicated in GERD, so no need for abx 8 Antacids neutralize HCl here in lumen PPI block this pump H2 receptor antagonists bind here to block Histamine 9 Three H2 Blockers to know H2 Receptor Notes Antagonists (H2RA) Famotidine [Pepcid] All B2 blocks tx heartburn or sour stomach in OTC dosing; prescription dosing to treat duodenal ulcers Ranitidine [Zantac] Original Zantac pulled from US market in came back as 2019 after found to have carcinogenic famotidine [Zantac components, back with generic 360]* famotidine in 2021 Cimetidine [Tagamet] Also to treat heartburn, ulcers and GERD H2 blockers can cross the BBB (with difficulty) so careful with confusion in elderly * Note, the carcinogenic agent NDMA was also found in valsartan 10  Ultimately, H2RA and PPI are similar because both are trying to block acid in stomach, but PPI are more effective, but more toxic In either case, for demand symptom relief, use antacids SE: Since able to cross BBB, can cause SE like H2RA confusion, especially in elderly Teaching: Smoking can decrease effectiveness of Notes on this med Take 30-60 min before meal to decrease SE, can the Class be especially beneficial to take at night if heartburn wakes you up at night Also, no antacid 30-60 minutes within taking, interferes with absorption (this is the case for many meds) Although rare, do need to keep an eye on liver and kidneys, especially with long term use 11 The nurse is A. “Make sure you are taking the caring for a client medication with meals and at night.” with a diagnosis of gastroesophageal B. “The symptoms you describe could reflux disease indicate liver impairment. I will notify (GERD) who is the HCP.” receiving famotidine. The C. “Drinking alcohol while you take client reports this medication will cause these muscle weakness symptoms.” and dark urine. Which response D. “These symptoms frequently occur by the nurse is with famotidine and should diminish best? over time.” 12 Answer Night OK, but not with meals, 30-60 min before and usually 1x/day Answer B, liver impairment. We talked about jaundice and increased LFTs, now add muscle weakness and abd pain as other signs of liver injury We don’t know if they are taking alcohol, wording is the problem, but yes, alcohol may worsen the problem Liver injury is dangerous, need to report 13 Four PPIs to know PPIs -prazole Notes Omeprazole The first PPI [Prilosec] Esomeprazole Purple pill, used to give to all in [Nexium ] hospital Pantoprazole Used more often in hospital today, [Protonix] still under prescription Lansoprazole Very little difference between PPIs, [Prevacid] recognize names, but no need to differentiate 14 Proton Pump Inhibitors Notice that most are 24 hours and are in delayed –release gel capsules, so no crushing or splitting! 15  SE are due to long-term reduction of HCl acid in stomach: Reduce Ca absorption  increased risk osteoporosis Reduce Mg, B12, and iron absorption  should check levels every couple years for lifelong PPI users Increased risk of renal failure  check yearly PPI Side creatinine, more secondarily, also keep eye on hepatic labs (similar to H2RA) Effects Without our protective acidic barrier, more risk of infectious complications with PPI,  GI infection like C Diff (don’t start hospital pt on PPI unless have something serious like bleeding ulcer). Also some risk of pneumonia Three additional side effects seen in some studies, but much debate about Dementia, Cardiac issues and lowered efficacy of anti-platelet medications. (Note these, but we will not go deeper.) 16  When in doubt, don’t crush a PPI pill. Almost all XR so that only have to take pill 1x/day BUT: it may be possible to open the PPI capsule and sprinkle the contents on to soft food like applesauce, but Teaching then must swallow whole (only mention this if patient really struggling to swallow pill and is clear about instructions. Use teach back method!) 17 Antacids Calcium carbonate How does it work? Neutralizes the hydrochloric acid coming from stomach Chem just for fun: CaCO3 + 2HCl  CaCl2 + CO2 + H2O Don’t take more than 10 Tums/day, you can see here, that would be about 7500 mg or almost 8g, which is considered max dose, huge calcium load and could cause cardiac issues 18 Milk of magnesia Magnesium hydroxide Both antacid and to treat constipation Very effective as antacid, but will give you diarrhea, so can take with aluminum hydroxide, which constipates to get balanced effect We made cocktail drinks for constipated patients with this & prune juice 19 Mylanta Aluminum hydroxide + magnesium hydroxide For all these antacids, keep an eye on sodium levels for heart failure patients Often on sodium-restricted diets to avoid fluid accumulation 20 Sucalfrate or bismuth subsalicylate [Pepto] Both coat the stomach Plan to take on an empty stomach (remember, empty stomach means 1 hr before meal or 2 hours after) For Pepto, instructions on back are focused on diarrhea. Taking on empty stomach is specific to this use for PUD. Also note ingredient in Pepto, part of the salicylate family with aspirin 21 Laxatives Chapter 82 22 Laxatives Start basic, some fiber or stool softener (also called surfactant)  “bulk forming”, help bring water to the stool Not really to treat existing constipation, but helpful for prevention Help the poor med out! Drink lots of water We use a lot in hospitalized patients to prevent constipation when they’re stuck in bed all day, often taking pain meds Usually give daily with AM meds Like all meds to help with BM, should only use short term But could take take 1-3 days to work 23 Psyllium fiber is in Metamucil, docusate sodium has brand name Colace 24 25 26 Stimulant Laxatives Stimulant laxatives like senna [Senokot] or bisacodyl [Dulcolax], but many brand names], cause contraction of smooth muscle in bowels to stimulate peristalsis By rectal suppository or by mouth; Which is faster? Don’t need a BM everyday, but why might we be more likely to use these with cardiac patient, for example? **BUT can become dependent on these 27 Osmotic Laxatives These are your more Names: serious evacuators Like enemas Polyethylene glycol (PEG), lower And colonoscopy prep doses = Miralax, but in different formations with electrolytes and Higher risk of higher dosing, we can use this for dehydration because bowel prep, called GoLytely pull out more water with stool, drink up! Mineral oil enema, lubricates pathway Mg can accumulate for for stool, side effect anal leakage renal pts Again, be careful giving anything with extra sodium to HF patient 28 SE and Drug interactions GI SE like bloating, gas, nausea and stomach cramping is expected, but if you don’t have a BM after 12 hours and you’re feeling more serious abd pain and actual vomiting, the concern is that there may be an intestinal blockage and that would be a clinical emergency Antacids, H2 blockers and PPIs may interact with stimulant laxatives Specifically, dairy and antacids can cause the enteric coating to dissolve too fast, so best to take separately Dulcolax is coated to prevent gastric irritation 29 Other GI Drugs Chapter 83 30  Anti-diarrheal Loperamide Works by binding to mu-opioid receptors in gut to slow contraction/peristalsis, so more time for water to get reabsorbed out of GI tract  stool is more formed and BM comes more slowly 31 SE loperamide SE: Dizziness and dry mouth, but also diarrhea itself dehydrates a person and can intensify both those effects, so drinking more is a plus for numerous reasons Drowsy so don’t take with other meds that can make you drowsy, or dangerous compounded effect (for this next exam, another med that makes you very drowsy = antihistamines) Can cross BBB at higher doses Thought-provoking question: if loperamide binds at opioid receptors, could that cause an opioid-like response? 32  A. “Take 2 tables after every Educational Q (Do loose bowel movement.” together in class): A B. You may be extra alert client diagnosed with and restless when taking gastroenteritis is this medication.” instructed to take loperamide for episodes C. “This medication may of diarrhea. Which cause you to have a dry information does the mouth.” nurse include when D. “It is safe to take this teaching the client about this medication? medication with other medications.” 33 Answer Dosing 2 pills (4mg) after loose BM, then 2mg after each BM, but can only do 8mg in 24 hr period Don’t drink tonic water, though, because contains quinine and loperamide can cause QT prolongation We know it causes drowsiness, so careful taking with any other CNS depressant or any other med that causes QT prolongation 34 Anti-emetics 🤢 You will give meds to prevent nausea and vomiting often in nursing! Most of these meds block receptors in the Chemoreceptor trigger zone (CTZ) 35 Classes of meds we have learned previously that have an anti-emetic effect 🤢: 1. Bismuth subsalicylate [Pepto-Bismol] 2. Benzodiazepines: lorazepam [Ativan] 3. Glucocorticoids: beclomethasone to prevent, not to treat active nausea, so may be given in combination with others 4. Antihistamines and scopolamine can help with motion sickness 5. Didn’t discuss before, but cannabis, especially for more serious chemotherapy-induced nausea and vomiting (CINV) 36  Two very common meds Anti-emetic, Serotonin Antagonist: Ondansetron [Zofran] Pro-kinetic agent: Metoclopramide [Reglan] Ondansetron 4mg IV push x1 PRN for N/V If ondansetron ineffective, metoclopramide 10mg IV push x 1 PRN for N/V Both can be given PO, but need to make sure will not vomit up (order will read, if not tolerating 37 PO)  MOA: serotonin antagonist in CTZ Let’s think: remember from Lesson 3, serotonin agonists? What did they help with? SE: HA is common, often standing order for acetaminophen for PRN Ondansetron pain relief [Zofran] Dangerous SE: QT Prolongation (keep thinking about other meds that increase risk!) May be combined with a glucocorticoid like dexamethasone or methylprednisolone for improved antiemetic effect 38  Blocks dopamine receptors in the CTZ Think about this: remember other meds in Lesson 3 that blocked dopamine receptors? What does pro-kinetic mean? Increases tone and mobility of GI tract (peristalsis) Metocloprami SE: sedation (think CNS effect) and de [Reglan] diarrhea (think pro-peristalsis effect) Dangerous SE: extrapyramidal SE like tardive dyskinesia with long- term, high-dose therapy (Excellent website on TD: https://www.tardiveimpact.com/what -is-td ) 39 Promethazine [Phenergen] Use Antihistamine and antiemetic…..Med does it all! Treat motion sickness, allergies, N/V and pain Can do all this because binds & blocks everything: histamine, alpha-adrenergic, muscarinic, dopaminergic Used as adjunct to pain medication because sedating and anti-emetic, so can be helpful after surgery with stronger analgesic to allow patient to rest, BUT many SE because many receptors: 40  Promethazine SE Have to monitor for over sedation (plus confusion and disorientation) Check for bradypnea = low RR Nystagmus = uncontrolled eye movements Tinnitus = ringing in ear Tachycardia Considered “high alert” medication, can cause severe damage to tissue 41 The nurse is administering promethazine IV to a patient. Which of the following precautions is most important to take? 1 2 3 4 A) Dilute the B) C) Ensure D) Inject the drug in 50 Administer the medication mL of normal the drug medication is into the saline. rapidly. administered muscle. via a large vein. 42 Answer Ensure the medication is administered via a large vein. Explanation: Promethazine can cause severe tissue injury, including gangrene, if it infiltrates surrounding tissues. It is crucial to administer it via a large vein and monitor the IV site closely for any signs of infiltration. Additionally: Burning and pain at the injection site may indicate extravasation, which can lead to severe tissue damage. The infusion should be stopped immediately to prevent further injury. 43 Gastrointestinal anti-spasmodic Relax muscles of GI tract Med: hyoscyamine to treat spasms, so have Hye-oh-SYE-a-meen less pain, like we see in Remember: these made irritable bowel syndrome (IBS) the Beers List Anticholinergic effects 44  So you don’t have to run back to Week 2 PPT…