GI PHARM 重點整理.docx

Week 8B: Gastrointestinal **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,...

Week 8B: Gastrointestinal **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 **Drugs for Peptic Ulcer Disease** **What do we mean by PUD?** 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 **Treatment for PUD** 1. Antibiotics to treat *H. pylori* (Usually 2) 2. Antisecretory agents A. H2 receptor antagonists --tidines B. Proton pump inhibitors (PPI) --prazoles 3. Mucosal protectants C. Sucalfrate D. Bismuth subsalicylate \[Pepto-Bismol\] 4. Antacids E. Calcium carbonate F. Magnesium hydroxide G. Aluminum hydroxide **Additional Notes on Treatment for PUD** New med Talicia since 2019 contains 2 antibiotics (rifabutin and amoxicillin) + omeprazole in a single capsule that a new PUD patient would take for 14 days and then re-evaluate 4 pills, 3x/daily Traditionally, patient will have to continue with **8-week PPI trial**, take PPI like omeprazole 1x/day, [30-60 min before meal ] Any PPI will work, most OTC now Always looking for "lowest effective dose" Only some people would stay on PPI for life (more severe damage to esophagus) **What about GERD? Often self-treat** **Three H2 Blockers to know** +-----------------------------------+-----------------------------------+ | **H2 Receptor Antagonists | **Notes** | | (H2RA)** | | +===================================+===================================+ | **Famotidine \[Pepcid\]** | **All B2 blocks tx heartburn or | | | sour stomach in OTC dosing; | | | prescription dosing to treat | | | duodenal ulcers** | +-----------------------------------+-----------------------------------+ | **Ranitidine \[Zantac\] came back | **Original Zantac pulled from US | | as famotidine \[Zantac 360\]\*** | market in 2019 after found to | | | have carcinogenic components, | | | back with generic 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** | +-----------------------------------+-----------------------------------+ **H2RA Notes on the Class** - 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 confusion, especially in elderly - Teaching: Smoking can decrease effectiveness of this med - Take 30-60 min before meal to decrease SE, can 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 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 **Four PPIs to know** 加圖表 **PPIs -prazole** **Notes** ------------------------------- ------------------------------------------------------------------------------------ Ome**prazole** \[Prilosec\] The first PPI Esome**prazole** \[Nexium \] Purple pill, used to give to all in hospital Panto**prazole** \[Protonix\] Used more often in hospital today, still under prescription Lanso**prazole** \[Prevacid\] Very little difference between PPIs, recognize names, but no need to differentiate **Proton Pump Inhibitors (PPI)** 1. Notice that most are 24 hours and are in delayed --release gel capsules, so no crushing or splitting! 2. PPI Side Effects 3. SE are due to long-term reduction of HCl acid in stomach: 4. Reduce Ca absorption increased risk osteoporosis 5. Reduce Mg, B12, and iron absorption should check levels every couple years for lifelong PPI users 6. Increased risk of renal failure check yearly creatinine, more secondarily, also keep eye on hepatic labs (similar to H2RA) 7. 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 8. 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.) **PPI Teaching** - 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 capsule and sprinkle the contents on to soft food like applesauce, but then must swallow whole (only mention this if patient really struggling to swallow pill and is clear about instructions. Use teach back method!) **Antacids** **Milk of magnesia** - 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 **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 **Sucalfrate or bismuth subsalicylate \[Pepto\] 會考** - 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 **Laxatives** - [Start basic(lowest therapiual doze, bc we don't want to have se)], 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** - Psyllium fiber is in Metamucil, docusate sodium has brand name Colace - - - **Osmotic Laxatives** - These are your more serious evacuators - Like enemas - And colonoscopy prep - Higher risk of dehydration because pull out more water with stool, drink up! - Mg can accumulate for renal pts - Again, be careful giving anything with extra sodium to HF patient **Names:** Polyethylene glycol (PEG), lower doses = Miralax, but in different formations with electrolytes and higher dosing, we can use this for bowel prep, called GoLytely Mineral oil enema, lubricates pathway for stool, side effect anal leakage **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 tha[t would be a clinical emergency] - Antacids, H2 blockers and PPIs may interact with stimulant laxatives - - Dulcolax is coated to prevent gastric irritation **Other GI Drugs** **Anti-diarrheal** - **Loperamide** **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? **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) 1. 2. 3. 4. 5. **Two very common meds 會考** 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 PO) **Ondansetron \[Zofran\]** - 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 pain relief - Dangerous SE: **QT Prolongation** (keep thinking about other meds that increase risk!) 會考 - May be combined with a glucocorticoid like dexamethasone or methylprednisolone for improved antiemetic effect **Metoclopramide \[Reglan\]** - 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) - SE: sedation (think CNS effect) and 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]](https://www.tardiveimpact.com/what-is-td) ) **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: **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 會考，會給iv - Stop the med and check it, if the pt said feel skin is burining **Gastrointestinal anti-spasmodic** - Relax muscles of GI tract to treat spasms, so have less pain, like we see in irritable bowel syndrome (IBS) - **Med: hyoscyamine** - Hye-oh-SYE-a-meen - Remember: these made the Beers List 最好不要用在老人身上 - Anticholinergic effects So you don't have to run back to Week 2 PPT...