Digestion

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Aminosalicylates

AVL: PO, PR. IND: UC and CD-not very effective. MOA: Anti-inflammatory that inhibits nuclear factor kappa B and chemoattractant leukotrienes which alters prostaglandin metabolism. EVD: Time to effect 2-4w. ADM: AE: Abdominal pain, cramps, diar, headach, naus, rash including urticaria, vom, interstitial nephritisrare, pancreatitisrare, pneumonitisrare, pericarditisrare, hepatitisrare. OTH: Main drug=5-aminosalicylic acid (5-ASA).
5-ASA=Asacol: PK: Gets released primarily in the colon. DOS: Flare up: Max=4.8g/d in divided doses. Maintenance=1.6 g/d in divided doses.


5-ASA=Mesasal: PK: Gets released in the SI so it works from the SI to the colon. DOS: Flare up=1.5–3g/d in divided doses. Maint=1.5g/d in divided doses.


5-ASA=Mezavant: PK:Gets released primarily in the colon. DOS: Flare up= 2.4–4.8g once/d. Maint=2.4g once/d.


5-ASA=Pentasa: PK: Gets released primarily in the colon. DOS: Flare up=2–4g/d in divided doses. Maint=1.5–3g/d in divided doses.


5-ASA=Salofalk: PK: Gets released in the SI so it works from the SI to the colon. DOS: : Flare up=3–4 g/d in divided doses. Maint=1.5–3g/d in divided doses.


olsalazine=Dipentum: AVL: PO. IND: 2nd line for UC. DOS: Flare up=500mg QID. Maint=500mg BID. OTH: 5-ASA dimer linked by azo bond that gets cleaved into 2 molecules of 5-ASA.
sulfasalazine (SSZ)=Salazopyrin: AVL: Tab or compounded suspension. EVD: May be more effective than 5-ASA but has least favourable AEs. ADM: AE: Naus, headache, rash, haemolytic anemia and hepatotoxicity. Reversible oligospermia reported w/ sulfasalazine, but not with 5-ASA. PK: Gets released primarily in the colon. DOS: Flare up=1-2g TID-QID. Maintenance=1g BID-TID. OTH: Different class but gets cleaved into 5-ASA.

 

Alginates

IND: GERD. MOA: Forms a foam barrier that floats to top of stomach. EVD: Provides symptom relief but does not prevent reflux.
alginic acid/Al hydroxide=Gaviscon liquid: AE: Naus, vom, belching, flatulence. DI: Binds w/ digoxin, tetracyclines, quinolones. PK: Onset=minutes. Duration=30-45min. DOS: 10-20mL prn after meals.


alginic acid/Mg hydroxide=Gaviscon Tabs: IND: GERD. ADM: Follow w/ glass of water. AE: Naus, vom, belching, flatulence. DI: Binds w/ digoxin, tetracyclines, quinolones. PK: Onset=minutes. Duration=30-45min. DOS: Chew 2-4 tabs prn after meals.


 

H2 Receptor Antagonists (H2RA)

IND: GERD. EVD: All 4 H2RAs have similar efficacy. ADM: T 30min before meal. OTH: Can develop tolerance/tachyphylaxis.
cimetidine=NU-CIMET: AVL: PO. AE: Diar, const, headache, fatigue, confusion, gynecomastiarare, impotencerare. DI: High potential to increase drug levels. PK: Inhibits: 1A2, 2C9, 2C19, 3A4 and 2D6. DOS: Adj for renal fxn. 800mg once/d or 600mg BID or 300mg QID.


famotidine=Pepcid: AVL: PO. PK: Does not inhibit CYPs. DOS: Adj for renal fxn. 10-40mg BID.


nizatidine=Axid: AVL: PO. AE: Diar, const, headache, fatigue, confusion. DOS: 150mg BID.


ranitidine=Zantac: AVL: PO. AE: Diar, const, headache, fatigue, confusion. PRG: Safe. LAC: Safe. DI: warfarin. PK: Doesn't inhibit CYPs. DOS: 75-150mg BID-QID or 300mg qHS. Non-Rx dose=75–150 mg/d. OTH: Schedule: U, III, I (depending on strength&size).


 

Laxatives

5-HT4 RECEPTOR AGONIST

prucalopride=Resolor: AVL: PO. IND: Chronic constipation for females who have failed alternatives. MOA: 5-HT4 receptor agonist with prokinetic activity. COS: ~$100/month DOS: 2mg once/d. D/C if not effective after 4w.


BULK FORMING LAXATIVES

calcium polycarbophil=Prodiem: OTH: synthetic fiber with less chance of flatulence, bloating.


inulin=Benefibre:


psyllium=Metamucil:


GUANYLATE CYCLASE-C AGONISTTS

linaclotide: AVL: PO. IND: Chronic adult constipation after failing laxatives. MOA: Guanylate cyclase-C receptor agonist which leads to increased chloride and bicarb in the intestines. This decreases absorption of sodium increased water secretion into the intestine. COS: =$120/month. DOS: Constipation=145 mg once/d.


LUBRICANT LAXATIVE

mineral oil: AVL: PO (liquid), PR (enema). IND: Constipation. MOA: Lubricates GI tract to aid stool passage and slows water reabsorption in the GI tract. PK: PO onset=6-8h.


OSMOTIC LAXATIVES

MOA: Sugar isn’t broken down and osmotically draws fluid in lumen and stimulates peristalsis.


glycerin: AVL: PR (rectal suppositories).
lactulose: PRG: Safe. LAC: Safe. PK: Onset=24-48h.


magnesium hydroxide=Milk of Magnesia: AVL: PO (oral susp).


polyethylene glycol (PEG 3350)=Lax-A-Day=Restoralax: AVL: PO (oral powder to make solution).


sorbitol: AVL: PO, PR.


STIMULANT LAXATIVES

bisacodyl=Dulcolax: AVL: PO, rectal suppositories.


sennosides=Senokot=Ex-Lax=Prodiem:


STOOL SOFTENERS

docusate sodium=Colace:


docusate calcium=Soflax: PRG: Safe. LAC: Safe.


 

Proton Pump Inhibitors (PPIs)

MOA: Block final step of acid secretion by irreversibly binding and inhibiting the H+/K+ ATPase (AKA the proton pump) in parietal cells of the stomach. DI: Reduced gastric acidity will changes absorption of drugs that are pH dependent (ex. ketoconazole, itraconazole or erlotinib)ref. PPIs should be taken at least 30min before sucralfate so that PPI absorption is not affected. Some reports of increased INR and prothrombin time in pts taking PPIs and warfarinref. PK: All PPIs are competitive inhibitors of 2C19. Order from strongest to weakest 2C19 inhibitors: lansoprazole, omeprazole, esomeprazole, pantoprazole, rabeprazole. MON: If treating GERD there should be significant improvement at 2wks. If not investigate further. Follow up at 4-8w. OTH: Goal w/ PPI is to make stomach pH>4. Beers criteria: Consider avoiding in pts >65yo because of risk of bone loss/fracture. Should also limit to 8w of use if possible. PPIs decrease both basal and stimulated acid secretion in the stomach leading to higher pH.
dexlansoprazole=Dexilant: AVL: PO (delayed release cap30, 60mg) ref. IND: GERD, esophagitis ref. EVD: Shouldn’t be used if <1 yo because it wasn’t effective at treating symptomatic GERD in a multicenter, double-blind controlled trial ref. ADM: T w/ or without food. Don’t cut or chew. Applesauce: May open cap and mix in 1 tbsp of applesauce. Don’t chew granules and eat full amount. Syringe: Open cap into 20mL of water, use syringe to draw up liquid, gently swirl, spray into mouth, reload syringe w/ 10mLs of water, spray in mouth and repeat once again to drain all the granules. NG tube: Use same syringe technique ref. AE: Diar4%, abdominal pain3%, Naus2%, flatulence2%, Const1%. May decrease absorption of: Vit B12, Mg+2, K+1, and Ca+2. May increase osteoporosis risk ref. Warning: Admin w/ rilpivirine CI. May mask ulcer symptoms. May increase risk of GI infections (ex C.difficile) ref. PRG: No safety data ref. LAC: No safety data ref. DI: Clopidogrel AUC was decreased 9% when given w/ dexlansoprazole 60mg/d. May elevate [methotrexate] when MTX is given at high dose. May effect absorption or clearance of antiretrovirals. May increase [tacrolimus]. Take >30min before sucralfate to increase [dexlansoprazole] ref. PK: t1/2=1-2hrs. PB=97%. Vd=40.3L. MM=369.36g/mol. Dexilant has a “Dual Delayed Release” w/ a concentration peak at 1-2hrs followed by a second at 4-5hrs. Met by 2C19 and 3A4. May slightly inhibit 2C19. Dexlansoprazole is R-enantiomer of lansoprazole. Not expected to be removed from dialysis ref. COS: $279 for 100x60mg caps2019. Not covered in AB, BC, MB, NB, NL, NS, ON, PE, SK. AUX: Don't Crush or Chew ref. MON: Re-evaluate at 4-8wks to see if still necessary. ref. DOS: >12yo: Esophagitis healing= 60mg once/d x up to 8wks. Esophagitis maintenance=30mg/d. GERD: 30mg once/d x4wks. Max of 30mg/d if moderate hepatic impairment. Severe hepatic impairment not studied. No dose adj for renal fxn. No dose adj for elderly. Not studied in pts <12yo ref. OTH: Stopping could cause rebound acid hypersecretion ref.
esomeprazole=Nexium: AVL: PO (delayed release tabs20, 40mg, sachet10mg) ref. IND: GERD, NSAID induced ulcers, Ellison syndrome, H. pylori (w/ clarithromycin and amoxicillin) ref. EVD: Found superior vs ranitidine 150mg BID when using non-selective NSAIDsref. ADM: T w/ or without food. May disperse tab in half glass of water. Stir until disintegration and drink whole glass within 30min. Rinse glass w/ water and drink. Don’t crush or chew pellets. For NG tube: Disperse tab in 50mL of water, draw up w/ syringe, admin through tube, flush tube w/ 25-50mL of water. ref. AE: Diar6%, abdominal pain5%, Const2%, May decrease absorption of: Vit B12, Mg+2, K+1, and Ca+2. May increase osteoporosis risk. Withdrawal may lead to rebound acidity ref. Warning: May mask ulcer symptoms. May increase risk of GI infections (ex C.difficile) ref. PRG: No safety data ref. LAC: No safety data ref. DI: Admin w/ rilprivirine CI. Clopidogrel’s active metabolite decreased by ~40% when also taking esomeprazole 40mg. May elevate [methotrexate] when MTX is given at high dose. Nexium 30mg/d x 5d decreased diazepam clearance by 45%. May increase [tacrolimus] and [phenytoin]. ref. PK: t1/2=1.4hrs. tmax=1-2hrs. F~75%. Vd=0.22L/kg. PB=97%. Met by 2C19 and 3A4. MM=713.1 g/mol. Esomeprazole is S-isomer of omeprazole ref. COS: $218 for 100x40mg tabs2019. Covered in MB, NL, ON, QE, SK. Partially covered in BC. Not covered in AB, NB, NS, PE. AUX: None ref. MON: Follow up at 4-8w to see if Tx still necessary ref. DOS: Adult: Reflux Esophagitis=40mg once/d x 4-8wks. GERD/esophagitis/NSAID induced GERD=20mg once/d. Zollinger-Ellison Syndrome= 40mg BID. H.pylori=20mg BID x 7d (combo Tx). No dose adj for elderly. No dose adj for renal fxn. Max 20mg/d for severe hepatic impairment. Peds (1-11yo): Esophagitis: <20kg=10mg once/d x8w. >20kg=10-20mg once/d x8w. NERD: 10mg once/d x 8w regardless of weight. Safety not established <1yo ref.
lansoprazole=Prevacid: AVL: PO (delayed release caps and tabs15, 30mg)ref. IND: Ulcer, NSAID induced ulcer, GERD, Zollinger-Ellison Syndrome, H.pylori (combo Tx)ref. ADM: Food decreases peak concentration and absorption by ~60% (T before breakfast). May open caps and put in applesauce, juice, water, and through NG tube. The “FasTabs” can be placed on tongue to dissolve, placed in water and drawn up w/ oral syringe, or given via NG tube via syringeref. AE: Diar4%, abdominal pain2%, dizziness1%. May decrease absorption of: Vit B12, Mg+2, K+1, and Ca+2. May increase osteoporosis riskref. Warning: May mask ulcer symptoms. May increase risk of GI infections (ex C.difficile)ref. PRG: Safe in rabbits and rats. Not human dataref. LAC: Excreted in milk of rats. No human dataref. DI: No dose adj for clopidogrel (no clinically important effect on [clopidogrel metabolite] or platelet inhibition). May increase [tacrolimus] and decrease [theophylline]. May elevate [methotrexate] when MTX is given at high dose. May affect absorption of protease inhibitorsref. PK: t1/2=1.5hrs. tmax=1.7hrs. Duration=>24hrs. Vd=16L. PB=97%. F=~83%. MM=369.37g/molref. COS: $67 for 100x30mg caps2019. Covered in AB, MB, PE, QE, SK. Partially covered in BC, ON. Exception status in NB, NL, NS. AUX: None. DOS: Adult (>11yo): Duodenal/gastric ulcer=15mg once/d x ~4wks. NSAID ulcer=15-30mg once/d up to 8wks. GERD=15mg once/d. H.pylori=30mg BID x 7-14d (combo Tx). Zollinger-Ellison Syndrome=60mg once/d. Max 30mg/d for elderly. No dose adj for renal fxn. Consider lower dose if severe hepatic disease. Ped (1-11yo): GERD: 15mg (weight<30kg) and 30mg (weight>30kg) once/d up to 12wks. Safety and effectiveness not established <1yoref.
omeprazole=Losec: AVL: PO (delayed release cap10, 20mg) ref. IND: GERD, NSAID induced GI lesions, reflux esophagitis, duodenal/gastric ulcers, Zollinger-Ellison Syndrome ref. EVD: ~80% decrease of 24hr gastric acidity after repeated 20mg/d doses ref. ADM: T w/ sufficient water w/ or without food ref. AE: Diar2.8%, headache2.6%, flatulence2.3%, abdominal pain 2%, Const1%, dizziness/vertigo1%. May decrease absorption of: Vit B12, Mg+2, K+1, and Ca+2. May increase osteoporosis risk. Withdrawal may lead to rebound acidity ref. Warning: May mask ulcer. May increase risk of GI infections (ex C.difficile) ref. PRG: Safety not established ref. LAC: Safety not established ref. DI: Could decrease [clopidogrel]. Decreases diazepam clearace by 26-40%. May elevate [methotrexate] when MTX is given at high dose. Phenytoin clearance reduced when omeprazole given at 40mg/d. May effect absorption or clearance of antiretrovirals. May increase effect of warfarin ref. PK: t1/2=40min. F=35-43%. Tmax=4hrs. PB=95%. MM=345.42g/mol. Met by 2C19 (major) and 3A4 (minor) ref. COS: $37 for 100x20mg caps2019. Covered in AB, MB, NB, NL, NS, ON, PE, QE, SK. Partially covered in BC. AUX: Don’t Crush or Chew. ref. MON: Healing of ulcers/esophagitis happens in 2-4w. Trial D/C after 4w. ref. DOS: Adult: GERD/Esophagitis/Ulcer: 20mg once/d x 4wks. Maintenance dose=10mg/d. Refractory esophagitis=40mg/d. No dose adj for kidney fxn. Don’t exceed 20mg/d in elderly or severe liver disease. Not studied in children ref.
pantoprazole Mg+2=Tecta: AVL: PO (EC tab40mg) ref. IND: GERD, reflux esophagitis, duodenal/gastric ulcers, H.pylori (in combo w/ Abx) ref. EVD: At 40mg/d acid production was inhibited 51% Day 1 and 85% on Day 7. Acidity was reduced by 37% on Day 1 and 98% on Day 7 ref. ADM: T in AM before, during, or after breakfast. Don’t crush or chew ref. AE: Headache2%, Diar2%, Naus1%. May decrease Vit B12 absorption and increase risk of osteoporosis ref. Warning: Could mask stomach ulcers symptoms. Increased risk of GI infections (ex. C.difficile) due to less stomach acid ref. PRG: No data for humans ref. LAC: Crosses into breast milk. No safety data ref. DI: Some reports of increased INR when used w/ warfarin. Increased levels of methotrexate when MTX used at high dose ref. PK: t1/2=~1hr. tmax=2.5hrs. F=77%. PB=98%. MM=825.08g/mol. Cmax is ~70% of pantoprazole Na+1 values. Met in liver. Doesn’t induce or inhibit enzymes ref. COS: $33 for 100x40mg tabs2019.Covered in AB, BC, MB, NB, ON, PE, QE, SK. Exception status in NL, NS. AUX: DON’T CRUSH OR CHEW ref. MON: GERD: If symptomatic after 4wks investigate further ref. DOS: Adult: GERD/gastric or duodenal ulcer: 40mg once/d x 4wks. H.pylori: 40mg BID x7d. Not studied in children. Choose alternative in sever hepatic disease. No dose adj for renal fxn ref. OTH: Amount of Mg+2 in each tab is negligibly low. Have been reports of false-positives for THC urine screening ref.
pantoprazole Na+1=Pantoloc: AVL: PO (EC tab20, 40mg) ref. IND: GERD, NSAID induced GI lesions, reflux esophagitis, duodenal/gastric ulcers ref. ADM: T w/ or without food. Do not crush or chew ref. AE: Headache2%, Diar2%, Naus1%. May decrease Vit B12 absorption and increase risk of osteoporosis ref. Warning: Could mask stomach ulcers symptoms. Increased risk of GI infections (ex. C.difficile) due to less stomach acid. PRG: Risk for humans unknown ref LAC: Does get excreted in breast milk. Safety not established ref. DI: Some reports of increased INR when used w/ warfarin. Increased levels of methotrexate when MTX used at high dose ref. PK: t1/2=~1hr. tmax=2-3hrs. F=77%. PB=98%. MM=432.4g/mole. Met by 2C19 and 3A4 ref. COS: $34 for 100x40mg tabs2019. Covered in AB, MB, NB, NS, ON, PE, QE, SK. Partially covered in BC. Exception status in NL. AUX: DON’T CRUSH OR CHEW ref. MON: Further investigation should be done if symptomatic after 4wks ref. DOS: Adult: GERD: 40mg once/d x 4wks. May use 20mg once/d for maintenance/healing of reflux esophagitis and NSAID induced lesions. No adj for renal fxn. Severe liver disease: max=20mg/d. Not studied in children ref.
rabeprazole=Pariet: AVL: PO (EC tab10, 20mg) ref. IND: GERD, duodenal/gastric ulcers, Zollinger- Ellison syndrome ref. ADM: T w/ or without food. Don’t crush or chew ref. AE: Diar3%, rash, dizziness. May decrease Vit B12 absorption and increase osteoporosis risk. Withdrawal could cause rebound acid secretion that starts within days and last up to 11 months ref. Warning: Could mask symptoms of stomach ulcer. Increased risk of gastrointestinal infections (ex. C.difficile) because of decreased stomach acid. ref PRG: Safety not established ref. LAC: Safety not established ref. DI: Some reports of increased INR when used w/ warfarin. Increased levels of methotrexate when methotrexate used at high dose. ref PK: t1/2=~1hr. Cmax=1.6-5hrs. F=52%. PB=96%. MM=381.43g/mol. Antisecretion stars within 1hr. Max effect after 2-4hrs. Met by CYP450s but does not inhibit or induce. ref. COS: $27 for 100x20mg tabs2019. Covered in AB, BC, MB, NB, NL, NS, ON, PE, QE, SK. Only PPI covered for BID dosing in NS. AUX: DON’T CRUSH OR CHEW ref. MON: Should D/C after 4-6 weeks and see if pt still needs it ref. DOS: Adult:GERD: 10 or 20mg once/d. Max=20mg BID. Tx should only be for 4-6w then reassess. Adj dose for severe hepatic impairment but not renal impairment. Not studied <18yo ref.
 

Purine Antimetabolites

IND: UC and CD. Used to reduce the dose of prednisone and maintain remission of quiescent disease (not inducing remission). MON: CBC q2w while titrating dose then q month. Can cause leukopenia/myleosupression. LFTs q2w then monthly (hepatotoxicity). Symptoms of pancreatitis – naus/vom/arthralgia (flu like Sx). OTH: Time to effect=3-6 months.
azathioprine (AZA)=Imuran: AVL: PO. AE: Naus, Diar, stomatitis, arthralgias, anorexia, opportunistic infection, blood dyscrasias, pancreatitisrare, hepatotoxicityrare DOS: 1-2.5mg/kg/d. OTH: Prodrug to 6MP.


6-mercaptopurine (6MP)=Purinethol: AVL: PO. AE: Naus, diar, stomatitis, arthralgias, anorexia, opportunistic infection, blood dyscrasias, pancreatitisrare, hepatotoxicityrare. DOS: Adj for renal fxn. 100mg/d.


 

AVL: IND: MOA: EVD: ADM: AE: CI/Warning: PRG: LAC: DI: PK: COS: AUX: MON: DOS: OTH:
AVL: IND: MOA: EVD: ADM: AE: CI/Warning: PRG: LAC: DI: PK: COS: AUX: MON: DOS: OTH:


AVL: IND: MOA: EVD: ADM: AE: CI/Warning: PRG: LAC: DI: PK: COS: AUX: MON: DOS: OTH:


AVL: IND: MOA: EVD: ADM: AE: CI/Warning: PRG: LAC: DI: PK: COS: AUX: MON: DOS: OTH:


AVL: IND: MOA: EVD: ADM: AE: CI/Warning: PRG: LAC: DI: PK: COS: AUX: MON: DOS: OTH:


AVL: IND: MOA: EVD: ADM: AE: CI/Warning: PRG: LAC: DI: PK: COS: AUX: MON: DOS: OTH: