GI Flashcards

Question

Stimulant Laxatives: -Drugs/Brands -MOA -ROA -Administration considerations -TX -AVEs -Warnings

Answer 1

Drugs: *senna (Ex-Lax, Senokot, w/ docusate - Senna S, Senokot S*, Senna Plus), *bisacodyl (Dulcolax*, Fleet Bisacodyl) MOA: *directly stimulate neurons in colon, causing peristaltic activity* ROA: PO, PR (Dulcolax) Administration: -Onset of action: 6-12 hours (PO), 15-60 minutes (PR) -*Take PO products at bedtime to induce bowel movement during morning* -Can give 30 minutes after meal to enhance peristalsis TX: *constipation, opioid-induced constipation* AVEs: *abdominal cramping*, electrolyte imbalance, rectal irritation (suppository) Warnings: avoid use w/ stomach pain, N/V, or sudden change in bowel movements that last > 2 weeks

Answer 2

Drugs: *docusate sodium (Colace*), docusate calcium, docusate potassium, *w/ senna (Senna S, Senokot S, Senna Plus)* MOA: *reduce surface tension of stool, allowing more water to mix with water to soften fecal mass and allow easier defecation* ROA: PO, PR Administration: -Onset of action: 12-72 hours (PO), 2-15 minutes (PR) -Do NOT take docusate and mineral oil together (increases absorption of mineral oil) TX: *constipation when stool hard or dry -Preferred when straining should be avoided* (ex. postpartum, post-MI, anal fissues, hemorrhoids) AVEs: abdominal cramping, throat irritation (liquid) CIs: abdominal pain, N/V, use w/ mineral oil, OTC use >1 week

Answer 3

Drug class: *lubricant* MOA:* coat bowel and stool with waterproof film to keep moisture in stool* ROA: PO, PR Administration: -Onset of action: 6-8 hours (PO), 2-15 minutes (PR) -Take multivitamin at different time due to malabsorption of fat-soluble vitamins -Do NOT take docusate and mineral oil together (docusate increases absorption of mineral oil) -PO formulation generally NOT recommended due to safety concerns (ex. risk of aspiration, lipid pneumonitis) TX: *constipation* AVEs: abdominal cramping, nausea, incontinence, rectal discharge CIs: age <6 yo, pregnancy, bedridden pts, elderly, use >1 week, difficulty swallowingDrug class: lubricant

Answer 4

Brand: *Amitiza* MOA: *chloride channel activator in gut, increasing fluid secretion and peristalsis* ROA: PO Administration: -Take with food and water to decrease nausea -Consider alternative TX with methadone (decreases lubiprostone effects) TX: *chronic idiopathic constipation (CIC), IBS-C in adult women, OIC* AVEs: *nausea*, diarrhea, abdominal pain, abdominal distention, HA CI: mechanical bowel obstruction

Answer 5

Drugs: *linaclotide (Linzess)*, plecanatide (Trulance) MOA: *increase Cl and bicarbonate secretion into lumen of intestines, increasing speed of GI transit and reducing abdominal pain* ROA: PO Administration: -Swallow Linzess capsules whole --> if needed, can open the capsule and mix contents w/ applesauce or room temperature water and swallow immediately -Trulance tablets can be crushed TX: *CIC, IBS-C* AVEs: diarrhea, abdominal pain, flatulence CI: age <6 yo, mechanical GI obstruction BBW: do NOT use in pediatric pts (high risk of dehydration and death)

Answer 6

Drugs: *alvimopan (Entereg), methylnaltrexone (Relistor), naloxegol (Movantik)*, naldemedine (Symproic) ROA: PO Administration *(alvimopan): maximum 15 doses in 7 day span* TX: *hospitalized surgery pts to decrease risk of post-operative ileus (alvimopan), OIC (methylnaltrexone, naloxegol, naldemedine)* CI (*alvimopan): therapeutic doses of opioids >7 consecutive days immediately prior to use* BBW (alvimopan): *potential risk of MI w/ long-term* use (available only for short-term inpatient use w/ REMS program)

Answer 7

Brand: Motegrity MOA: *5-HT4 receptor agonist to release ACh causing muscle contractions and increasing GI motility* ROA: PO TX: *chronic idiopathic constipation (CIC)* AVEs: *diarrhea*, HA, nausea, abdominal pain Warnings: *suicidal ideation* CI: GI obstruction, GI perforation, ileus, severe inflammatory conditions of GI tract (Crohn's disease, ulcerative colitis, toxic megacolon) Monitoring: worsening of depression or emergence of suicidal thoughts, rectal bleeding, blood in stool, severe abdominal pain

Answer 8

Drugs: *polyethylene glycol-electrolyte solution (Colyte, GoLytely*, NuLytely, GaviLyte-G, GaviLyte-N, MoviPrep, Plenvu), *sodium phosphates (OsmoPrep), sodium sulfate, potassim sulfate, and magenesium sulfate (Suprep Bowel Prep Kit*), sodium picosulfate, magnesium oxide, and citric acid (Clenpiq) Administration: -Onset of action 1-6 hours -*Bowel prep regimens typically require doses the evening before colonoscopy and the morning of colonoscopy to completely evacuate the bowel -Clear liquid diet* is required the day prior to colonoscopy and can include: water, clear broth (beef or chicken), juices w/o pulp, soda, coffee, or tea (w/o milk or cream), clear gelatin (w/o fruit pieces), popsicles (w/o fruit pieces or cream) -DO NOT consume the following: *solid or semi-solid foods, anything w/ red or blue/purple food coloring*, milk, cream, tomato, orange or grapefruit juice, alcoholic beverages, cream soups AVEs: abdominal discomfort, bloating, N/V Warnings: arrhythmias, electrolyte abnormalities, seizures CIs: ileus, GI obstruction, gastric retention, bowel perforation, toxic colitis, toxic megacolon -*OsmoPrep: acute phosphate nephropathy, gastric bypass or stapling surgery* -Clenpiq: severe renal impairment BBW *(OsmoPrep): nephropathy*

Answer 9

Diarrhea: increase in number of bowel movements or stools that are more watery and loose than normal Causes: most cases are viral, some bacterial (E. coli most common, IBS-D (idiopathic diarrhea associated w/ chronic or recurring abdominal discomfort relieved by defecation) Non-pharmacotherapy: -Fluid and electrolyte replacement especially in children or older adults -Oral rehydration solutions (ORS) - ex. Pedialyte, Enfamil Enfalyte -Alternative: Gatorade Drug TX: -Viral infections often resolved w/o TX -Non-infectious diarrhea symptomatic relief (OTC): bismuth subsalicylate or loperamide --> refer if age <6 months, pregnancy, high fever (>101F), severe abdominal pain or blood in stool -RX: diphenoxylate/atropine, dicyclomine (anticholinergic - helps w/ cramping), eluxadoline -IBS-D when other TX has failed: eluxadoline (Viberzi), rifaximin (costly), alosetron (women only)

Answer 10

GI drugs: -Antacids containing magnesium -Drugs for constipation (laxatives) -Misoprostol -Prokinetic drugs (ex. metoclopramide, cisapride) Others: -Acetylcholinesterase inhibitors (ex. donepezil) -Antidiabetics (ex. metformin, GLP-1a) -Antineoplastics (ex. irinotecan, capecitabine, fluorouracil, MTX, TKIs) -Colchicine -Mycophenolate, Roflumilast

Answer 11

Brand: *Pepto-Bismol* MOA: *anti-diarrheal* ROA: PO AVEs: *black tongue/stool* (temporary and harmless), salicyclate toxicity (if used excessively: *tinnitus*, metabolic acidosis), *nausea*, abdominal pain -Can cause increased risk of bleeding when used w/ anticoagulants, antiplatelets, or NSAIDs Warnings: *children and teenagers who are recovering from the flu, chickenpox, or other viral infections should NOT use this drug due to risk of Reye's Syndrome* CIs: *salicyclate allergy, taking other salicyclates (ex. ASA), GI ulcer, bleeding problems, black/bloody stool*

Answer 12

Brand: *Imodium A-D*, Anti-Diarrheal, Diamode MOA: *anti-diarrheal* ROA: PO Dosing: *4mg PO after first loose stool then 2mg after each subsequent loose stool (max: 8mg/day for self-care or 16mg/day under healthcare supervision)* Administration: -*For self-TX, do NOT use >48 hours* -Loperamide can be abused as it causes mild opioid-like "high" in large quantities -*FDA requires use of blister packs *or other single-dose packaging for tablets/capsules and number of doses per package to be no more than 48mg (24 tablets/capsules) AVEs: *constipation*, abdominal cramping, nausea, QT prolongation CIs: *acute dysentery* (bloody diarrhea and high fever - drug stops gut which is trying to get rid of toxin), *pseudomebranous colitis (C. difficle), bacterial enterocolitis* caused by invasive organsisms (toxigenic E. coli, Salmonella, Shigella), abdominal pain w/o diarrhea, acute ulcerative colitis BBW: Torsades de pointes, *cardiac arrest and sudden death w/ doses higher than recommended, children < 2 yo (risk of toxic megacolon)*

Answer 13

Brand: *Lomotil* MOA: *anti-diarrheal* -Atropine: discourages abuse ROA: PO *Administration:* -Control schedule: CV -Liquid formulatoin is recommended in children <13 yo AVEs: mild euphoria due to diphenoxylate, *possible anticholinergic effects (from atropine - mild at recommended doses)* CI: risk of respiratory and CNS depression (*do NOT use if <2 yo of age or <6 yo for tablets*), diarrhea caused by endotoxin-producing bacteria or pseudomembranous colitis (C. difficile), obstructive jaundice

Answer 14

Brand: *Bentyl* MOA: *antispasmodic* ROA: PO TX: *diarrhea* AVEs: *dizziness, dry mouth, nausea, blurred vision*, somnolence, weakness, nervousness Warnings: *anticholinergic (caution in pts >/=65 yo, Beers Criteria), caution in mild-moderate ulcerative colitis (can cause toxic megacolon or paralytic ileus)* CI: GI obstruction, severe UC, reflux esophagitis, acute hemorrhage w/ CV instability, obstructive uropathy, narrow-angle glaucoma, myasthenia gravis, breastfeeding women, infants <6 months

Answer 15

Brand: Viberzi MOA: *peripherally-acting mixed mu-opioid receptor agonist* ROA: PO TX: IBS-D AVEs: constipation, nausea, abdominal pain Warnings: CNS depression CIs: *pts w/o gallbladder*, biliary duct obstruction, sphincter of Oddi dsyfunction/disease, pancreatitic disease (hx of pancreatitis), alcoholism, or >3 alcoholic drinks/day, severe hepatic impairment (Child Pugh Class C), hx of severe constipation, GI obstruction Monitoring: s/sx of pancreatitis or sphincter of Oddi spasm (ex. adbdominal pain that radiates to the back or shoulder, N/V), LFTs

Answer 16

IBD: *group of inflammatory conditions of colon and small intestine that is chronic, intermittent with flares and remissions* Differences from IBS: -*IBS does NOT have inflammation* and is not as serious of a condition -*Classic symptom of IBD: bloody diarrhea* Ulcerative colitis (UC): mucosal inflammation confined to rectum and colon w/ superficial ulcerations -*Distal disease: when UC limited to descending colon and rectum -Proctitis: inflammation limited to rectum* -Classified as mild, moderate (>4 stools/day), severe (>/=6 bloody stools w/ evidence of toxicity), or fulminant (>10 stools/day and severe symptoms) Crohn's disease (CD): deep, transmural (through bowel wall) inflammatoin that can affect any part of GI tract (most commonly: ileum and colon) *UC vs. CD:* -Diarrhea: bloody (UC, CD), or non-bloody (CD) -Fistulas/strictures: commo in CD, but not UC -Location: entire GI tract (especially ileum and colon - CD), colon (especially rectum - UC) -Depth: transumral (CD), superficial (UC) -Pattern: non-continuous "cobblestone" appearance (CD), continuous (UC) Diagonosis: *colonoscopy with tissue biopsy* -Rule out other conditions

Answer 17

-Diet: *eating smaller, more frequent meals; low fat and dairy diet; fiberous foods; drink plenty of water (avoid alcohol, caffeinated, and carbonated beverages); avoid foods with sorbitol and lactose* -*Vitamin supplementation to prevent defeciences*: B12, folate, vitamin D, calcium, iron, zinc -Smoking: shown to worsen CD, but may be protective in UC -*Probiotics: Lactobacillus or Bifidobacterium infantis can reduce abdominal pain, bloating, urgency, constipatoin, or diarrhea in some pts* -Natural products (limited evidence): fish oils, pepermints (oils or teas), chamomile, horehound, wheatgrass

Answer 18

General TX: -Induce remission/for acute exacerbations: short-course steroids (IV or PO) that should be tapered over 8-12 weeks once remission achieved -Maitenance of remission: biologics in moderate or severe UC or CD; for mild, up to three months of therapy with budesonide for CD and mesalamine for UC CD: -Mild disease of ileium and/or right colon: PO budesonide for in distal, rectal preferred; in extensive, rectal +/- PO -Moderate/severe (preferred): anti-TNF agent (golimumab, adalimumab, infliximab) w/ or w/o thiopurine, IL receptor antagonist, integrin receptor antagonist -Moderate/severe (alternative): janus kinase inhibitor, oral sphingosine-1-phosphate receptor modulator

Answer 19

1. Entocort EC; both; Uceris; induction; CYP3A4 (caution w/ grapefruit) 2. Undergoes extensive first-pass metabolism, resulting in decreased systemic exposure than other PO steroids 3. 2 weeks; adrenal suppression; BMD; vitamin D and calicium supplementation; bisphosphonates 4. hydrocortisone; budesonide; UC; induction (hydrocortisone - maybe maintenance in mild distal UC as alternative to aminosalicyclates

Answer 20

Brand: *Pentasa*, Apriso, Delzico, *Asacol HD*, Liaida, *Rowasa, Canasa* MOA: *aminosalicyclate - anti-inflamamatory effect in GI tract (metabolite of sulfasalazine)* ROA: -ER capsules: *Pentasa*, Apriso, Delzicol -ER tablets: *Asacol HD*, Liadia -*Enema: Rowasa -Suppository: Canasa* Administration: -Mesalamine better tolerated than other aminosalicyclates (ex. sulfasalazine, balsalazide, olsalazine) -*Rectal mesalamine more effective than PO and rectal steroids for distal disease/proctitis in UC* -Can use PO and topical formulations together -*Asacol, Delzicol: can leave ghost tablet* -Swallow capsules/tablets whole --> do NOT crush, cehw, or break due to DR coating -Apriso: do NOT use w/ antacids (dissolution is pH-dependent) -*Administer enemas and suppositories in evening, just before bedtime. Try not to have bowel movement until morning. Can stain surfaces including clothing and fabrics* TX: *UC induction*

Answer 21

AVEs: abdominal pain, nausea, HA, flatulence, eructation (belching), nasopharyngitis Warnings: -Acute intolerance syndrome (cramping, acute abdominal pain, bloody diarrhea) -Caution in pts w/ renal or hepatic impairment -Delayed gastric rentetion (due to pyloric stenosis) can delay release of PO products in colon -*Hypersensitivity rxns* (including myocarditis, pericarditis, nephritis, hematologic abnormalities, and other internal organ damage) --> *more likely w/ sulfasalazine than mesalamine* -Increased risk of blood dyscrasias in pts >65 yo -Photosensitivity -Apriso: contains phenylalanine --> do NOT use in PKU -Rowasa: enema contains potassium metabisulfite (may cause allergic-type reaction) CIs: *hypersensitivity to salicyclates or aminosalicyclates* Monitoring: renal function, CBC, hepatic function, s/sx of IBD

Answer 22

Drugs: azathioprine (Azasan, Imuran), mercaptopurine (Purixan) MOA: *immunosuppressive* ROA: PO TX: *inducation and maitenance of remission for CD and UC* Administration (mercaptopurine): take OES; *avoid old terms "6-mercaptopurine" or "6-MP" - increased risk of overdose due to doses 6-fold higher than normal* AVEs: N/V/D, rash, increased LFTs Warnings: hematologic toxicities (leukopenia, thrombocytopenia, anemia); pts with *genetic deficiency of thiopurine methyltransferase (TPMT) are at increased risk for myleosuppression (consider testing before starting)*; GI hypersensitivity rxns (severe N/V/D, rash, fever, increased LFTs); hepatotoxicity BBW: chronic immunosuppression increases risk of malignancy with IBD (especially lymphomas); mutagenic potential; risk of hematologic toxicities Monitoring: LFTs, CBC (weekly for first month), renal function, s/sx of malignancy DDIs: -*Azathioprine metabolized to mercaptopurine: do NOT use in combo* -Aminosalicyclates inhibit TPMT, caution in combination -Allopurinol inhibits pathway for inactiavtion of azithoprine --> dose reduction required if used in combination

Answer 23

1. -*Sulfasalazine: more AVEs due to sulfonamide compontent (CI: salicyclate allergy, sulfa allergy) -Balasalazide: can stain teeth and tongue* 2. *Methotrexate; Cyclosporine* 3. Janus Kinase Inhibitors: -UC: tofacitinib (Xeljanz), udadacitinib (Rinvoq) -CD: upadacitinib (Rinvoq) S1P Receptor Modulators: for UC --> ozanimod, etrasimod *Anti-TNF MABs: for moderate/severe UC or CD often in combo w/ thiopurine --> infliximab, adalimumab* Interluekin receptor antagonists: for moderate/severe disease -UC and CD: ustekinumab (Stelara) and its biosimilar (Wezlana) -CD: risankizumab (Skyrizi) -UC: mirikizumab-mrkz (Omvoh)

Answer 24

Brand: *Entyvio* MOA: *integrin receptor antagonist -MAB that binds to subunit of integrin molecules that inhibits interactions with adhesion molecules and preventing inflammatory cells from migrating into GI tissue* ROA: *IV* Administration: -*D/C if no benefit by week 14* -Refrigerate and store in original packaging to protect from light -Swirl during reconstitution, do NOT shake -Cannot be used w/ other immunosuppressants TX: *induction and maitenance of remission in moderate/severe IBD* AVEs: HA, nasopharyngitis, hypersensitivity, arthralgia, antibody development Warnings: *infusion rxns*, hypersensitivity rxns, *infections*, liver injry, PML (lower risk than w/ natalizumab) -*All immunizations must be up to date before starting*: avoid live vaccines during TX Monitoring: LFTs, s/sx of infection, hypersensitivity, neurological symptoms (for PML), routine TB screening

Answer 25

Brand: *Tysabri* MOA: *integrin receptor antagonist -MAB that binds to subunit of integrin molecules that inhibits interactions with adhesion molecules and preventing inflammatory cells from migrating into GI tissue* ROA: *IV* Dosing frequency: *Q4 weeks* Administration: -*D/C if no response by 12 weeks* -Cannot be used with other immunosuppressants (if taking steroids when initiating, begin tapering when benefit is observed, stop natalizumab if pt cannot taper steroids within 6 months of initiation) -Stable in NS only; do NOT shake TX: *induction and maitenance of remission in moderate/severe IBD* -Rarely used for CD due to risk of PML AVEs: infusion rxns, HA, fatigue, arthralgia, nausea, rash, depression, gastroenteritis, abdominal/back pain Warnings: herpes encephalitis and meningitis, hepatotoxicity, hypersensitivity (antibody formations), immunosuppression, infections BBW: *progressive multifocal leukoencephalopathy (PML* - opportunistic viral infection of brain that leads to death or severe disability) -*Only available through REMS program* -Monitor: mental status changes, risk factors (anti-JCV antibodies, increased TX duration, and prior immunosuppressant use)

Answer 26

Vertigo: dizziness with the sensation that *environment is moving or spinning* typically a condition in inner ear that affects balance -*TX: vestibular (inner-ear) suppressants including antihistamines (ex. meclizine, dimehydrinate) and BZDs -5-HT3 receptor antagonists are NOT useful for vertigo since they do NOT affect inner ear*

Answer 27

Motion Sickness: dizziness with *sensation of being off-balance and woozy* due to repetitive motions -Nonpharmacological: acupuncture bands, *ginger* -*Antihistamines: diphenhydramine (Benadryl), dimenhydrinate (Dramamine), meclizine (Dramamine Less Drowsy*, Bonine) -*Anticholinergics: scopalamine patch - not any more effective than OTCs, but applied behind ear and lasts three days* -*Promethazine: Rx only for motion sickness when antihistamines NOT effective, do NOT use in children* due to risk of respiratory depression (BBW: avoid in <2 yo and strongly against >2 yo) -*Metoclopramide and 5-HT3 receptor antagonists generally NOT effective for motion sickness* -*Take PO medications 30-60 minutes before needed effect*

Answer 28

Brand: *Transderm Scop* MOA: *anticholinergic* ROA: *patch* *Administration/Counseling:* -Press 1 patch firmly to skin behind ear for 30 seconds at least 4 hours before effect needed, apply Q3 days PRN -Avoid placing patch over hair or when patch is removed. Hair may be removed too -Wash hands after applying -Do NOT drive: high level of drowsiness, dizziness, and confusion -Avoid alcohol while wearing patch -Do NOT use in children TX: *motion sickness (try to avoid in elderly)* AVEs: *dry mouth, CNS effects (drowsiness, dizziness, confusion - can be significant in elderly, frail), stinging of eyes and pupil dilation* (if eyes are touched after handling), *risk of increased IOP*, tachycardia (rare), *withdrawl symptoms* (diaphoresis, dizziness, fatigue, HA, nausea) after D/C (can last several days) CI: *hypersensitivity to belladonna alkaloids, closed-angle glaucoma*