GI pharm exam 5

GI defenses

mucus

bicarbonate

blood flow

prostaglandins

GI invaders

H.PYLORI

NSAIDS

gastric acid

pepsin

smoking

gastric ulcer

less common than duodenal ulcer

other causes of ulcers

stress

alcohol

gastric ulcer symptoms

pain 30-1h right after eating

food inc pain

weight loss

HCL normal or hyposecretion

vomiting

duodenal ulcer symptoms

2-3h after eating

food can dec pain

most common

well nourished

stress ulcers

from shock, cushing’s, burns, brain injury

gastroesophageal reflux disease (GERD)

chronic condition characterized by persistent heartburn

lower esophageal sphincter is weak/relaxes

dec salivary secretions

diminished esophageal motility

symptoms of GERD

heartburn

dysphagia

dyspepsia

chest pain

nausea

belching

h.pylori treatment

2-3 antibiotics

amoxicillin, clarithromycin, tetracycline, metronidazole, tinidazole, bismuth compounds

PLUS

antisecretory agents

PPI or histamine 2 receptor antagonists (H2RA)

antacids

neutralize or buffer stomach acid

MOM, aluminum hydroxide, calcium carbonate, sodium bicarbonate

H2RA

block bodies signal to stomach to produce acid

cimetidine, famotidine, nizatidine

PPI

blocks secretion of acid into stomach

omeprazole. esomeprazole, lansoprazole, dexlansoprazole, pantoprazole

antacids characteristics

alkaline substances neutralize stomach acid to treat PUD and heartburn symptoms

Magnesium hydroxide (MOM)

high acid neutralizing capacity

rapid and long lasting

diarrhea

malox

combination of MOM and aluminum hydroxide

aluminum hydroxide

slow but long lasting

low ANC

constipation

hypophosphatemia

calcium bicarbonate

rapid and long lasting

high ANC

constipation, belching, flatulence

take antacid when

apart from other med (1-2H)

sodium bicarbonate

rapid and short lasting

RARELY for PUD/GERD

treat acidosis

\*baking soda\*

histamine 2 receptor antagonists H2RA

supresses gastric acid secretion

H2RA drugs

famotidine

cimetidine

H2RA pharmokinetics

rapid absorption from small intestine

30 min onset of action, 1/2 life 1-4 hours

PO,, IV, IM

avoid taking with antacids (PO)

take before meals or with

AE H2RA

uncommon

pneumonia

CNS effects (high doses in elderly) with confusion, restlessness, hallucinations, depression

AE cimetidine (H2RA)

antiandrogenic effects (gynecomastia, reduced libido, impotence)

hypotension and dysrhythmias (IV)

inhibits metabolism of warfarin, phenytoin, theophylline

proton pump inhibitors

most effective for suppressing secretions of gastric acid

ulcer prevention in those taking NSAIDs

PPI drugs

omeprazole

lansoprazole

well tolerated

take 30min before 1st meal

PPI drugs are

PRAZOLE drugs

AE PPI

HA

n/v/d

c diff infection risk

pneumonia

long term use:

fracture, hypomagnesemia, gastric cancer

PPI interactions

some HIV/AIDS drugs, ketoconazole, itraconazole, clopidogrel

sucralfate (carafate)

activates in acidic environment to form sticky gel that adheres to ulcers

lasts up to 6 hours

no serious AE (constipation)

bismuth compounds (kaopectate, pepto-bismal)

for dyspepsia, heartburn, and diarrhea

disrupts cell wall of h.pylori

may cause black stool

misoprostol (cytotec)

only approved GI indication is to prevent gastric ulcers in patients on long term NSAIDs

AE of diarrhea, abd pain

PREGNANCY CAT X (can be used in L&D for uterine contraction)

metoclopramide (reglan)

short term therapy in patients who fail to response to first line agents

promotes gastric motility

laxatives

used to ease or stimulate defecations

softens stool

inc stool volume

hasten fecal passage through intestines

facilitate evacuation from rectum

laxative effect

production of soft, formed stool over 1+ days (mild)c

cathartic effect

prompt fluid evacuation of bowel (fast and intense)

laxative uses

fresh stool sample

empty bowel before treatment or procedure

expel dead parasites after treatment

modify effluent from ostomy

constipation

prevent fecal impaction in bedridden

remove poisons

laxative contraindication

abdominal pain

nausea

cramps

acute surgical abdomen

fecal impaction/bowel obstruction

habitual use

caution in pregnancy and lactation

laxative therapeutic effects group 1

watery stool in 2-6H

laxative therapeutic effects group 2

semifluid stool in 6-12h

laxative therapeutic effects group 3

soft stool in 1-3 days

types of laxative

bulk forming (group 3)

surfactant (group 3)

stimulant (group 2)

osmotic (group 1-2)

chloride channel activator (group 3)

bulk forming laxative drugs

psyllium (metamucil)

methylcellulose (citrucel)

polycarbophil (FiberCon)

bulk forming laxative characteristics

draws water into stool to make a gel to make it softer and inc fecal mass

for constipation

several doses may be needed over 1-3 days for optimal effect

functions like dietary fiber

MUST drink enough water

can be used daily

AE bulk forming laxatives

safest and rarely has

with insufficient water psyllium may swell in esophagus and cause obstruction

bulk forming laxatives contraindications/precautions

undiagnosed abd pain

suspected intestinal obstruction

fecal impaction

nursing actions in bulk forming laxatives

mix powder and granules with at least 8 ounces of pleasant tasting liquid

surfactants drug

docusate sodium (colace)

surfactants characteristics

lowers surface tension of stool allowing more water penetration to soften stool

may inc secretion and dec absorption of water and electrolytes in intestine

take with full glass of H2O

softens in 1-3 days

stimulants drugs

bisacodyl (dulcolax) oral or rectal, may have burning

senna (senokot) plant derived, may have harmless yellow brown or pink urine

castor oil (group 1) unpleasant taste mix with fruit juice

stimulants characteristics

stimulates intestinal motility

inc secretion and dec absorption of water and electrolytes in intestine

most are group 2

widely used and abused by public

used for constipation (opioid induced, slow intestinal transit)

osmotics

laxative salts

polyethylene glycol

lactulose

laxative salts

poorly absorbed salts

osmotic action draws water into intestine

fecal mass softens, swells, stretches intestinal wall, stimulates peristalsis

6-12h low dose, 2-6h high dose

laxative salt drugs

magnesium hydroxide/citrate/sulfate

sodium phosphate

AE laxative salts

substantial water loss (inc intake)

renal impairment (Mg toxicity)

sodium (fluid retention, heart failure, HTN, edema, renal failure)

polyethylene glycol drugs

miralax

polyethylene glycol

2-4 days

may cause bloating, cramping, flatulence, diarrhea

can be used daily

lactulose drug

constulose

lactulose characteristics

1-3 days

more expensive than bulk forming

may cause flatulence, cramping

enhances excretion of ammonia (can lower)

can have portal HTN, hepatic encephalopathy

chloride channel activator

lubiprostone (amitiza)

24H

for chronic constipation

IBS-C in women >18

opioid induced constipation

mineral oil

lubrication (useful as enema in fecal impaction)

may cause:

lipid pneumonia

anal leakage

mineral oil in liver

glycerin suppository

softens and lubricates impacted feces

may stimulate rectal contraction

30 min

after put in pinch cheeks close

bowel prep

1H

nausea, bloating, abd discomfort

sodium phosphate

hypertonic

can cause dehydration, electrolyte disturbances, renal damage

polyethylene glycol-electrolyte (goLYTELY)

isotonic

LARGE amount

diarrhea

symptom of GI disease

stools of excessive volume, fluidity, and frequency

diarrhea management

treat cause

replace fluid and salts

relieve cramps

reduce passage of unformed stool

most effective antidiarrheals

opioid because they slow peristalsis

most common opioids

diphenoxylate (lomotil) for diarrhea only (made with atropine to dec abuse) use amoxone for overdose

loperamide (imodium)

OTC antidiarrheals

bismuth subsalicylate (pepto-bismol)

bulk forming agents (absorbs some water)

other antidiarrheals

anticholinergic antispasmodics

difenoxin

paregoric

opium tincture

probiotics

correct altered GI flora

when to NOT use antidiarrheals

when trying to treat diarrhea caused by poisoning or infection by toxin producing organism

have to let them out

inflammatory bowel disease (IBD)

intestinal inflammation

exaggerated immune response

no cure just control disease processes

crohn’s and UC

abd cramping, diarrhea, rectal bleeding

crohn’s

main site is terminal ileum (but can be any part)

has skip lesions

affects thick layer of intestines

ulcerative colitis

only affects mucosal layer

continuous in colon and rectum

can treat with colon removal

drugs used to treat IBD

5-aminosalicylates (5-asa) sulfasalazine

glucocorticoids (prednisone)

immunosuppressants (azathioprine)

immunomodulators (infliximab)

antibiotics (metronidazole)

5 aminosalicylates

reduce inflammation

most effective in mild to mod UC

AE:

nausea, fever, rash, arthralgia, hematologic disorders, photosensitivity

interaction:

inhibits absorption of folic acid

warfarin (inc coagulant effect)

5 aminosalicylates drugs

sulfasalazine (azulfidine)

mesalamine (asacol)

olsalazine (dipentum)

balsalazide (colasal)

immunosupressants

long term therapy

induce/maintain remission (CD and UC)

AE of immunosupressants

pancreatitis

neutropenia

immunosupressant drugs

thiopurines:

azathioprine (imuran) and mercaptopurine (purinethol)

cyclosporine

methotrexate

immunomodulators (biologics)

dec immune system

monoclonal antibodies

take TB test

mod - severe CD and UC

AE of immunomodulators

infusion/injection site reactions

infection (TB and opportunistic)

inc risk of lymphoma

immunomodulators drugs

infliximab (remicade)

certolizumab pegol (cimzia)

adalimumab (humira)

natalizumab (tysabri)

vedolizumab (entyvio)

golimumab (simpronil)

ustekinumab (stelara)

irritable bowel syndrome (IBS)

most common disorder of GI tract

irritable bowel syndrome (IBS) symptoms

cramping abd pain (can be severe)

not explained by structural or chemical abnormalities

present for 12 weeks over past year

may occur with diarrhea (IBS-D), constipation (IBS-C), or both (IBS-M)

drugs used in irritable bowel syndrome (IBS)

antispasmodics (hyoscyamine and dicyclomine) (bentyl)

bulk forming agents

antidiarrheals

tricyclic antidepressant

IBS drugs

lubiprostone (amitiza) IBS-C in women >18

linaclotide (linzess) IBS-C >18

eluxadoline (viberzi) IBS-D

alosetron (lotronex) IBS-D in women, strict risk management

anticholinergic agents and antihistamines

for motion sickness (n/v, pallor, cold sweats)

anticholinergic agents and antihistamines drugs

scopolamine (oral, SQ, transdermal) can cause dry mouth, blurred vision, drowsiness, urinary retention, constipation, disorientation, (CANT PEE, SEE, SPIT, SHIT)

dimenhydrinate

meclizine

cyclizine (sedation, dry mouth, blurred vision, urinary retention, constipation)

serotonin (5HT3) receptor antagonist use

chemo induced n/v

post op

hyperemesis gravidarum

serotonin (5HT3) receptor antagonist drugs

ondansetron (zofran)

AE serotonin (5HT3) receptor antagonist

HA

diarrhea

dizziness

prolonged QT interval

benzodiazepines

ineffective when used alone

sedation

supress anticipatory emesis

retrograde amensia

chemo

lorazopam (ativan)

phenothiazines

prochlorperazine and promethazine (phenergan)

CINV, post op, toxins

AE:

EPS, sedation, hypotension, anticholinergic effects

promethazine can cause resp depression, and tissue injury

butyrophenones

haloperidol (haldol) and droperidol (inapsine)

for post op, CINV, toxins

AE:

EPS, sedation, hypotension

cannabinoids

dronabinol (marinol) and nabilone (cesamet)

for CINV, AIDS, anorexia

cause relaxation, less euphoria comp to marijuana

glucocorticoids

methylprednisolone (solu-medrol) and dexamethasone

for CINV