Gastrointestinal Agents

Front 1

Vomiting center

Back 1

In medulla. H1 and ACHm receptors.

Front 2

Chemoreceptor trigger zone

Back 2

Relays to vomiting center. D2 and 5-HT3 receptors

Front 3

Vestibular apparatus

Back 3

Relays to vomiting center. H1 and ACHm receptors.

Front 4

Vagus nerve and GIT

Back 4

Relays to/from vomiting center: 5-HT3 receptors

Front 5

ACHm

Back 5

Muscarinic Acetylcholine Receptor

Front 6

Antiemetics:D2

Back 6

Dopamine receptor

Front 7

Antiemetics:5-HT3

Back 7

Serotonin receptor

Front 8

Antiemetics:Non-pharmacologic N/V Tx

Back 8

Weak tea
Flat soda
Gelatin
Gatorade
Pedialyte
Dry crackers, toast
IV fluids PRN (rehydration can relieve S/S)
Ginger (relieves N, but does not stop V)

Front 9

Antiemetics:OTC Drug Tx for N/V

Back 9

Antihistamine (H1):
Dimenhydrinate (Dramanine)
Diphenhydramine (Benadryl)
Others:
Pepto-bismol
Emetrol

Front 10

Antiemetics: Rx Tx

Back 10

Antihistamines (H1)
Anticholinergics
Dopamine antagonists
Benzodiazepines
Serotonin (5-HT3) antagonists
Glucocorticoids
Neurokinin receptor antagonists
Cannabinoids (CA PTs)
Others

Front 11

Antiemetics:Rx Antihistamines

Back 11

H1: Hydroxizine (Vistaril - IV, Atarax - PO)
Promethazine (Phenergan) - most widely prescribed

Front 12

Antiemetics:Rx Anticholinergics

Back 12

Scopolamine (Transderm-Scop)

Front 13

Antiemetics:Anticholinergics: Scopolamine

Back 13

Small round disc, behind ear
-Travel/sea sickness: on cruises
-Terminal secretions (no more "death rattle") - ethical issues here.
Causes urinary retention

Front 14

Antiemetics:Antihistamines: Prototype

Back 14

Promethazine (Phenergan)

Front 15

Promethazine (Phenergan): Action, S/Es, A/Rx

Back 15

Action:Blocks H1 receptors; inhibits chemoreceptor trigger zone
S/E: drowsiness, confusion, A, dry mouth & eyes, constipation, blurred vision, photosens., HTN, hypotension, trans leukopenia, U retention.
A/Rx: EPS. Lf THr: Angranulocytosis, resp depres.

Front 16

Promethazine HCl (Phenergan): C/Inds, Caution

Back 16

C/Ind: Hypersen., N/A Glaucoma, severe L Dx, Int Ob, blood dyscras., bone marrow depres.,
Caution: CVD, L dysf., asthma, resp dysf., HTN, elderly/debilitated PTs

Front 17

Promethazine HCl (Phenergan): Tx effects/Uses; class; routes

Back 17

Ts and prevent motion sickness, N/V
Phenothiazine Antiemetic
PO, IM, Rectally (NOT via rectum for chemoTx PTs d/t bleeding/infx risk)

Front 18

Promethazine HCl (Phenergan): Pharmacokinetics/Dynamics

Back 18

PO, easily ab from GIT
PB: 60-90%
T 1/2: not known
Exc: U & F
PO onset 20 mins
Peak: UK
Duration: 2 - 8 hrs

Front 19

Rx antihistamines & anticholinergics: S/Es

Back 19

Drowsiness (hence O/L use as sleep aid)
Blurred vision (d/t dilated pupils)
Tachycardia w/ anticholinergics
Constipation (d/t ↓ perstalsis)

Front 20

Rx antihistamines & anticholinergics: Contra Inds/Caution

Back 20

NOT with glaucoma
NOTE drowsiness can be major problem: don't drive, etc!

Front 21

Phenothiazine Antiemetics: Promethazine (Phenergan)

Back 21

EPS in younger/smaller PTs
[Study: all PTs <110lbs got EPS]
GIVE PHENERGAN to chemoTx PT via PO!!! Pace story: gave via IM, bleeding d/t thrombocytopenia

Front 22

Phenothiazine Antiemetics: S/Es

Back 22

Some sedation
Hypotension
EPS (younger/smaller PTs thus ↓ dose with ↓ age/wt)
Lower doses: EPS rare unless chronic use (ie. 3 + days)
CNS effects: restlessness, weakness, dystonia
Mild anticholinergic S/S: dry mouth, U ret., constipation

Front 23

Other Dopamine Antagonists

Back 23

Butyrophenones
Metoclopramide

Front 24

Chlorpromazine (Thorazine)

Back 24

Not used so much as antiemetic
Used to Tx hiccoughs

Front 25

Butyrophenones

Back 25

Haloperidol (Haldol)
Droperidol (Inapsine)

Front 26

Butyrophenones: Uses

Back 26

Block D2 receptors in CTZ;
ST uses: post-op N/V
Emesis r/t toxins, CA chemo & radiation Tx

Front 27

Butyrophenones: S/E

Back 27

LT use: EPS
Main S/E: hypotension
May cause ↑ QT
D/T "out of skin" sensation, use of this drug falling out of favor

Front 28

Metoclopramide (Reglan): Action

Back 28

"Moves the food"
Block D2 receptors in CTZ
Prokinetic - coord contractions ↑ transit of UGI contents

Front 29

Metoclopramide (Reglan): Uses

Back 29

Post-op emesis, CA chemo & radiation Tx

Front 30

Metoclopramide (Reglan): S/Es, Contraindications

Back 30

High doses: sedation
EPS in children (↓ age, ↓ wt)
Contraind:
GIO, hemorrhage, perforation

Front 31

Benzodiazepines: Prototype

Back 31

Lorazepam (Ativan)

Front 32

Benzodiazepines: Action

Back 32

-Indirect control of N/V d/t chemoTx
-Provides sedation, ↓ anxiety, amnesia when used w/ glucocorticoid & serotonin 5-HT3 receptor antagonist

Front 33

Serotonin (5-HT3) Receptor Antagonist: Action, Routes

Back 33

-Block vagal nerve terminals in CTZ and UGIT
-Effective ↓ N/V B4/After surgery
-No EPS
Routes: PO, IV

Front 34

Serotonin (5-HT3) Receptor Antagonist: S/Es

Back 34

H/A, D, dizziness, fatigue

Front 35

Serotonin (5H-T3) Receptor Antagonist: Prototype

Back 35

Odansetron (Zophran)

Front 36

Glucocorticoids (Corticosteroids): Uses

Back 36

Suppress emesis r/t CA chemoTx
IV for ST - few S/Es

Front 37

Glucocorticoids (Corticosteroids): Examples

Back 37

Dexamethasone (Decadron)
Methylpredisolone (Solu-Medrol)

Front 38

Cannabinoids: Summary

Back 38

Relieve N/V d/t CA Tx
PTs not responding to other antiemetics
Contraindind for PTs w/ psych D/Os (d/t S/Es)

Front 39

Cannabinoids: S/Es, Notes

Back 39

Hallucinations
Illegal in some states
Smoking more effective
PO Cannabinoids less effective - Marinol

Front 40

Antiemetics: Nursing Dx

Back 40

Imbalanced nutrition: less than body requirements
Risk for fluid volume deficit r/t V

Front 41

Antiemetics: Nursing Assessment

Back 41

Hx: onset, freq., amount
Assess for hematemesis
Hx: chronic illness
Hx: previous food intake (seafood, mayonnaise? I.e., "food poisoning"?)

Front 42

Antiemetics: Planning

Back 42

PT will adhere to nonpharm methods &/or drug regimen to alleviate N/V

Front 43

Antiemetics: Teaching

Back 43

Avoid alcohol (↑ sedation)
Avoid driving/dangerous activites

Front 44

Antiemetics: Interventions

Back 44

Check V/S
Assess for dehydration
Assess for constipation/D (S/Es of many of these drugs)
Monitor BS: Hypoactivity/hyperactivity - rolling sounds: imminent V.
Provide oral care after V (enc. PT to maintain this: keep mouth clean)

Front 45

Emetics

Back 45

Induce V
Toxins ingested: expel before absorption
NOT if caustic substance, e.g., ammonia, bleach, HCL acid
(will cause tearing/erosion of esophagus)
CALL POISON CONTROL CENTER

Front 46

Emetics: Ipecac

Back 46

OTC, ↓ use
Not to be used routinely
Possibly OK if PT alert (knows what they took) and given w/in 60 mins
NGT/charcoal better than Ipecac

Front 47

Diarrhea: Summary

Back 47

Bristol Stool Scale
S/S of intestinal D/O
May be Life Threatening (dehydration)

Front 48

Diarrhea: Causes

Back 48

Foods
Bacteria
Viruses
Stress/anxiety
Bowel tumors
Inflammatory bowel Dx
Graft vs Host Dx (transplants)

Front 49

Diarrhea: Inflammatory bowel Dx

Back 49

Ulcerative colitis
Crohn's Dx

Front 50

Antidiarrheals: Opiates

Back 50

Opiates, opiate rel. subs
↓ peristalsis
Constipation common S/E
CNS depression if w/ alcohol, sedatives, tranquilizers
Duration: c. 2 hrs
IMPORTANT:Need to assess for Infx prior to meds admin. Must deal w/ cause before Tx S/S.

Front 51

Antidiarrheals: Examples

Back 51

Diphenoxylate (Lomotil) [more Rx than opiates]
Loperamide (Imodium)

Front 52

Diphenoxylate (Lomotil)

Back 52

Opiate antidiarrheal w/ atropine
↓ potential for dependence than other opiates
Often used for "Traveler's Diarrhea" (water-born E coli)
Physical dep. w/ LT use

Front 53

Loperamide (Imodium)

Back 53

Structurally sim to Lomotil but ↓ CNS depression
OTC
Protects vs D (↓ fecal volume, ↓ intestinal fluid and electrolyte losses)

Front 54

Antidiarrheals: Notes

Back 54

Not to be used with C diff.
W/ C diff. do not want to stop D: need to clear bacteria from GIT. If not removed, will be encapsulated and thus remaining untreated.
Must deal with cause of D before Tx of S/S.

Front 55

Opiates antidiarrheals

Back 55

NOT with severe L dysfx
Children, elderly at ↑ risk of resp. depression

Front 56

Somatostatin Analog

Back 56

Inhibits GI & pancreas hormones and transmitters.
Reduces intestingal fluid secretion & pancreatic secretions
Slows GI motility

Front 57

Somatostatin Analog: Prototype, route

Back 57

Octreotide (Sandostatin)
IV mostly but also SubQ

Front 58

Antidiarrheals: Adsorbents

Back 58

Bismuth salicylates (Pepto-Bismol)
OTC
Traveler's D and for GI discomfort

Front 59

Bismuth salicylates (Pepto-Bismol): Contraindications

Back 59

Not for Children w/ flu-like S/S etc (Reyes Syndrome)
Elder adult w/ fecal impaction

Front 60

Reyes Syndrome

Back 60

Acute non-inflammatory encephalopathy

Front 61

Antidiarrheals: Assessment

Back 61

Hx viral/bacterial infx, drugs, foods ingested
Check:
V/S, F & E losses
Hx narcotic drug abuse (opiate/opiate-rel antiD Rx)
Assess:
Frequency & consistency of stool
BS (hyperactivity)

Front 62

Antidiarrheals: Nursing Diagnoses

Back 62

D d/t infx
Potential for laxative abuse (esp. w/ elderly)
Imbalanced nutrition: less than body requirements
Risk for imbalanced fluid volume

Front 63

Antidiarrheals: Interventions

Back 63

Report HR >100 or systolic BP <10-15mm HG
Opiates/rel drugs → CNS depression
Check:
Freq BMs, BS
S/S dehydration, F & E imbalance
NOT WITH C-DIFF!!!

Front 64

Constipation: Summary

Back 64

Common problem for older adults
Nonpharm measures FIRST:
High fiber (bulk) diet
Water
Exercise
Routine bowel habits

Front 65

Laxatives & Cathartics

Back 65

AVOID if:
IO [Tumor most common cause]
Severe ab pain
Appendicitis
UC
Diverticulitis

Front 66

Cathartics: S/Es

Back 66

Griping, strong effect. Stronger than laxatives.

Front 67

Laxatives & Cathartics: Summary

Back 67

Abuse d/t chronic use problem esp. w/ elderly
Client teaching re. laxative dependence important nursing responsibility

Front 68

Laxatives & Cathartics: Types

Back 68

Osmotic (saline): salts, saline, lactulose, glycerin (glycerin is mild)
Stimulant (contact): Disacodyl (Dulcolax
Bulk-forming: Psyliium (Metamucil) - less pop. chalky, hard to use: PEG better - polyethylglycol)
Emolients (stool softeners): Docusate sodium (Colace)
[Golytely: 1L fluid, prior to colonoscopy/severe constipation, cleans out bowel

Front 69

PUD: summary

Back 69

Ulcers in espophagus, stomach, duodenum, UGIT
Burning epigastric pain, exacerbated by fasting, improved with meals
[Hypersecretion of acid, w/ food acid diverted to food]

Front 70

PUD: predisposing factors

Back 70

Mechanicl
Genetic
Environmental
H pylori
Drugs

Front 71

H Pylori: Summary

Back 71

Gram - bacillus
Oral
Recurrent PUD after Tx (if NOT caused by NSAIDS)
Past Dx by endoscopy: now breath test (Meretek UBT - 90-95% accurate)
Serology test for antibods to H pylori

Front 72

H Pylori: Tx

Back 72

Various Tx protocols
Resistance is problem
ABs Tx of choice
Combos w/ 2, 3, 4 drugs - based on PT's drug tolerance

Front 73

H Pylori: Drug Tx

Back 73

Common combos:
Metronidazole (Flagyl)
Omeprazole (Prilosec)
Clarithromycin (Biaxin)[Macrolide]
[Cannot have Biaxin w/ Antibuse or w/ alcohol]

Front 74

H Pylori: Dx Tests

Back 74

Meretek UBT: 90-95% effective
Endoscopy (in past)
Serology for antibodies

Front 75

GERD: causes

Back 75

Incompetent LES
Smoking, obesity

Front 76

GERD: Nonpharm Tx

Back 76

as PUD:
Avoid alcohol, smoking, hot/spicy foods
Wt loss if obese
Raise HOB
Don't eat before bed
Loose clothing
Small, freq meals/avoid large meals

Front 77

Antiulcer Drugs: Types

Back 77

Tranquilizers
Anticholinergics
Histamine2 blockers
PPIs
Pepsin inhibitors
Prostaglandin analoge

Front 78

Antiulcer Drugs: Tranquilizers

Back 78

Reduce vagal stimulation and anxiety.
Minimal antiulcer effect

Front 79

Antiulcer Drugs: Anticholinergics: Action

Back 79

Inhibit acetylcholine
Block H and HCl
Decrease motility and secretion (delay gastric emptying)

Front 80

Antiulcer Drugs: Anticholinergics: Uses

Back 80

Duodenal ulcers mostly
(less used for gastric Us)
Many S/Es
Less used than other Tx

Front 81

Antiulcer Drugs: Anticholinergics: Examples

Back 81

Belladonna tincture
Propantheline bromine (Probantine)

Front 82

Antacids: Actions, Types

Back 82

Neutralize HCl, reduce Pepsin
Systemic, Non-systemic
Mylanta,Maalox

Front 83

Systemic antacids: Summary, Types, Ex, S/Es

Back 83

Sodium Bicarbonate: S/Es - Na+ excess, metabolic acidosis
ex. Alka-Seltzer. Little used
Calcium Carbonate: most effective, 1/3 - 1/2 systemically absorbed
S/E: acid rebound, hypercalcemia
ex. TUMS

Front 84

Nonsystemic antacids: Summary, Types, Ex, S/Es

Back 84

Alkali salts (Al, Mg)
Little systemic absorption (Al)
Mg > effect than Al
S/E: Mg → D

Front 85

Antacids: Client Education

Back 85

2oz water after liquid antacid
1hr before, 3 hrs after meals
DELAYS absorption of other drugs
NO Mg w/ RF
Al(OH)3 Tx to ↓ phosphate level w/ RF

Front 86

Histamine2 Blockers: NOTE

Back 86

Note NOT same thing as H2 antagonists (diphenhydramine, loratidine)
Most popular antiulcer drugs

Front 87

Histamine2 Blockers: Action

Back 87

Histamine RECEPTOR antagonists
Block H2 receptors of PARIETAL cells
thus ↓ secretion & concentration of gastric acid
Prevent acid reflux in esophagus

Front 88

Histamine2 Blockers: Prototype

Back 88

Ranitidine (Zantac)

Front 89

Ranitidine (Zantac), Famotidine (Pepcid) cf w/ Cimetidine (Tagamet)

Back 89

More effective, longer lasting
Fewer S/Es
Fewer drug/drug interactions
Zantac < potent than Famotidine (Pepcid)

Front 90

Ranitidine (Zantac): S/Es

Back 90

H/A
N/D or Constpn
Vertigo
Depression
Blurred vision
Rash

Front 91

Ranitidine (Zantac): A/Rx

Back 91

hepatotoxicity
Cardiac dysrhythmias
Blood dyscrasias

Front 92

PPIs: Action

Back 92

↓ gastric acid secretion by inhibiting H+/K+ ATPase enzyme system in gastric parietal cells

Front 93

PPIs: Uses

Back 93

Effective ↓ gastric sectretions
Tx ulcers and GERD
Zolinger-Ellison sydrome (hypersecretion Dx)

Front 94

PPIs: Examples

Back 94

Lansoprazole (Prevacid)
Pantoprazole (Protonix)
Omeprazole (Prilosec)
Omeprazole & NaBiCarb (Zegerid) - w/ antiacid
[Rabeprazole (Aciphex), Esomeprazole (Nexium) not covered by most plans and less used - $$]

Front 95

PPIs: Prototype

Back 95

Lansoprazole (Prevacid)

Front 96

PPIs: Issues

Back 96

ST: few A/Rx
S/Es/A/Rx: H/A, dizziness, rash, ↑ AST, ALT
Risk of gastric CA w/ LT use (PTs lose track of how long they've been on it)

Front 97

Pepsin Inhibitor (Mucosal Protective Drug)

Back 97

Sucralfate (Carafate)
Complex sulfated sucrose & ALH
Combines w/ protein t form viscous substance covering ulcer (protects from acid, pepsin)
S/E: constipation