B5 GI-Renal Pharmacology Final Exam
2024 of2024
Promoters Gastric Acid Secretion - - Ach from vagus n (PS)
- Hist from enterochromaffin-like (ECL) cells
- Gastrin from G cells
Inhibitors of Gastric Acid Secretion - - Somatostatin from delta cells
- PGE2 from gastr muc
Pathophysiology & Common Sx of GERD - AKA acid reflux, heartburn
- Pathophys = stom cont/gastr ac reflux into esoph --> sx+complics; maybe by decr LES
press/musc tone --> treat by 1). incr LES press, 2). decr stom ac secr
- Common Sx = heartburn, hypersal, ac regurg, acidic taste
Alarm Sx & Complications of GERD - - Alarm sx = CP, dysphag, odynoph, anemia, GIB,
wt loss
- Complics = esoph eros, strics, bl, Barrett's esoph, adenocarc (rare)
2 Types of GERD - - Eros reflux dis = sx w/ muc dam
- Non-eros reflux dis (NERD) = sx w/o muc dam
Foods/Beverages Worsening GERD Sx by Decr LES Pressure - - fatty meal
- carminatives (ie. peppermint, spearmint)
- choc
- coffee, cola, tea
- garlic
- onions
- chili peppers
- EtOH esp wine
Meds Worsening GERD Sx by Decr LES Pressure - - Antichols
- Barbs
- Caffeine
- Dihydropyridine CCBs
- Dopa
- Estrogen
- Nic
- Nitrates
- Progesterone
- Tetracyc
- Theophylline
Foods & Drugs Worsening GERD Sx by being Direct Irritants to Esophageal Mucosa - -
Spicy foods
- Orange juice
- Tomato juice
- Coffee
- Tobacco
,B5 GI-Renal Pharmacology Final Exam
-2024
Asp 2024
- Bisphosphonates
- NSAIDs
- Fe
- Quinidine
- Potassium chloride
Non-pharmacological Treatments for GERD - - Lifestyle mods = wt loss if overwt; elev
head of bed, avoid meals >2-3hr before bed if nocturnal sx; psych stress red; avoid
smoking, trig foods+meds
- Surg = laparoscopic fundoplic, gastric bypass in obes gen not rec if not resp to PPIs
Pharmacologic Treatment Options for GERD - - Antacids --> neutr stom ac
- Hist-2 R Antags (H2RAs, ie. Cimetidine) --> block H2 rec basolat memb --> (-)
adenylyl cyclase, (-) cAMP --> (-) prot pump activ
- PPIs (ie. Omeprazole) --> prev ac secr by dir block H+ chann
- Sucralfate & Bismuth comps --> prot coat over ulcers
- Misoprostol --> stim PGE2 rec --> (+) Gi prot --> (-) AC & cAMP
Pharmacological Treatment Guidelines for GERD - - initial self-treat w/ OTC
antac/PPI/H2RA
- further treat if alarm sx, recur sx >2wks lifestyle mods/self-treat
- Pref empir ther = 8wks PPI QD
- Maint/Cont ther if recur sx >8wks PPI/eros esoph/BE --> PPI BID if unresp to QD,
H2RA if NERD but less effec than PPI
Pathophysiology of PUD - muc def gastr/duod wall from innermost muc into deeper lays
- epis gnaw epig pain relieved by eating if duod ulc, relieved by not eating if gastr ulc
- bl = most freq+sev complic; also perf, gastr out obstr
Common Causes & Dx of PUD - - H. pyl, chron NSAIDs incl Asp, physical stress
- dx via endoscopy; also H. pyl test by urea breath test, stool Ag
H. pylori General Features, Sx, Risk Factors - G- fec-or bac surv in ac EVRs by env in
neutr EVR by urea metab due to high urease activ conv urea to ammonia+CO2
- ammonia prev D cells antral gl sensing acidity --> (-) somatostatin --> (+) gastrin -->
(+) ac secr
- Sx = dyspep, epig abd p, GIB
- RFs = smoking, chron NSAIDs
Preferred First-Line Therapy Regimen for H. Pylori - Bismuth Quadruple Therapy x10-
14d
- Bismuth Salicylate
- Metronidazole
- Tetracyc
- PPI
,B5 GI-Renal Pharmacology Final Exam
2024 2024
-Doxy can be used in place of Tetracyc
- Tinidazole can be used in place of Metro
Concomitant nQuadruple nTherapy nfor nH. nPylori n- nx10-14d
- Clarithro
- Amox
- Metronidazole
- PPI
- Tinidazole ncan nbe nused nin nplace nof nMetro
Triple nTherapy nfor nH. npylori n- n2 nabx+PPI nx14d
- Clarithro
- Amox
- PPI
nOR
- Clarithro
- Metronidazole
- PPI
**AVOID nin nareas nClarithro nresis>15% nOR npts nw/ nprior nMacrolide nexpos nfor nany
nindic**
- Tinidazole ncan nbe nused nin nplace nof nMetro
Rule nfor nAbx nRx nfor nH. npylori n- nmust nhave n@ nleast n2 nabx nagents nin nquadruple
nther nw/ neach nabx nhaving ndiff nMOA
NSAID-Associated nUlcer nSx n& nTreatment n- nmost nw/ nasymp npep nulc, nless nw/
ncomplics nlike nbl, nperf
- Treatment n= ndiscont nNSAID nif nposs
1). 8wks nH2RA nor nPPI nfor nrap nulc nheal
- erad nther nif n+H.pyl
- if nNSAID nmust nbe ncont, nPPI nbetter nfor nulc nheal nbut nconsid nCOX-2 nsel
nNSAID n(ie. nCelecoxib) nbut nincr nthromb nrisk
Examples, nMOA, nIndications nfor nAntacids nin nGERD n& nPUD n- nincl nAl nhydrox, nCa
ncarb, nMg nhydrox, nNa nbicarb, ncombos
- MOA n= nweak nbases nneutr ngastr nac nto nincr ngastr npH
- fast-acting nw/in nmins n& nshort ndur n30-60mins
- Indics n= nmild ninfreq nindig/GERD; nCaCO3 n(ie. nTums) nfor nhypocal, noff-lab nfor
nosteop; nMg(OH)2 n(ie. nPhillips nMilk nof nMagnesia) nfor nhypomagnesemia,
nconstip; nNaHCO3 nfor ndiarr, nmetab nacid, ndrug ntox
**DOC nfor nGERD nin npreg**
, B5 GI-Renal Pharmacology Final Exam
2024
AEs, n 2024 for Antacids - - AEs = constip, hypercal, milk alkali synd for
CIs, Warnings
n n n n n n n n n n n n n
nCaCO3; nconstip, nhypophosph nfor nAl(OH)3; ndiarr, nhypermag nfor nMg(OH)2; ngastr
ndisten, nbelch, nmetab nalk nfor nNaCO3 n& nCaCO3
- CIs n= nhypercal nfor nCaCO3
- Warnings n= nAl n& nMg naccum nin nren ndysfunc n--> nDON'T ngive nif nCrCl<30
DIs nfor nAntacids n- nbind n& ndecr nabsorp ndrugs nreq nlow nstom npH nfor ndissol/absorp n--
> nsep ndosing nby nsev nhrs/@least n2 nhrs nfor nTetracyc, nFQs, nItraconazole, nIron
Examples, nMOA, nIndications, nTips nfor nH2RAs nfor nGERD n& nPUD n- n-idine
nsuffix nincl nFamotidine, nRanitidine, nNizatidine, nCimetidine n(all nOTC)
- MOA n= nhighly-sel nrev nblock nH2 nrec ngastr npar ncells n--> n(-) ngastr nac nsecr nto nincr
ngastr npH
- onset n<1hr, ndur n4-10hrs
- Indics n= nGERD, nPUD, nstress nulc nprophyl n(esp nICU npts)
- Tips n= ntake nbefore nmeals nfor nprophyl nto nred nheartburn nlikelihood; nPRN nfor ninfreq
n<2x/wk nheartburn/dyspep; nfreq nheartburn n>3x/wk/GERD nbettertreat nw/ nBID nH2RA
nor nQD nPPIs
Difference nin nGastric nAcid nInhibition nby nH2RA nvs. nPPI n- nH2RA ninhib nnocturnal nac
nsecr nthe nmost n& nPPI ninhib nALL nac nsecr
AEs n& nBBW nfor nH2RAs n- n- nCommon nAEs n= ndiarr/constip, nHA, nfatigue, nmyalgias
- IV nadmin nin ncrit nill npts n--> nincr nrisk nnosocom npneumo, nAMS nesp nelderly/ren/hep
ndysfunc
- BBW n= ngynectomastia/impot nin nmen/galactorr nin nwomen nw/ nLT nCimetidine
nby ninhib ndihydrotestost, nincr nser nprolactin nlevels nto nandrog nrec, ninhib
nestradiol nmetab
DIs nfor nH2RAs n- n- ndecr nabsorp ndrugs nreq nlow nstom npH nfor ndissol n(ie.
nKetoconazole)/absorp
- additive neffs nw/ nCNS ndeps nesp nincr nin neld nso nAVOID nCimetidine nin nelderly
- inhib ngastr n1st-pass nmetab nEtOH n--> nincr nbl nEtOH nlevels nexcept nFamotidine
- Cimetidine n--> n(-) nCYP450 nesp n1A2, n2C9, n2C19, n2D6, n3A4 n--> nCI nw/ nDofetilide
nb/c nincr nrisk nQT nprol
Examples, nGeneral nMOA, nIndications nfor nPPIs n- n-prazole nsuffix
incl nOmeprazole, nExomepra, nLansopra, nDexlansopra, nRabepra, nPantopra n(all nOTC)
- MOA n= nprodrugs nirrev nbind+inactiv nH+/K+-ATPase npar ncells
- take non nempty nstom n1hr nbefore nmeal nb/c ndecr nbioav n50% nw/ nfood;
nt1/2=1.5hrs; ndur n24hrs nb/c ntakes n>18hrs nfor ncells nto nexpr nnew nprot npumps
**Dose nadj nin nsev nliver nimpair**
- Indics n= nGERD; nPUD n(most nduod nhealed n4wks, nmost ngastr nhealed n8wks); nnon-
ulc ndyspep; neros nesophagitis; nesoph nstric; ngastr nhypersecr n(ie. ngastrinoma, nZES);
nstress nulc nproph n(ie. ncrit nill npts)
AEs n& nDIs nfor nPPIs n- n- nCommon nAEs n= nn/v/d/c, nHA
- LT nassoc nw/ nosteop, nbone nfx, nC.diff nesp nPantoprazole, npneumo, nmicronutr
ndefs nesp nMg2+ n& nB12, ndementia, nkidney ndis
