3/12/2016
1
Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.
Fall 2012
Acid-Controlling Drugs
HYDROCHLORIC ACID
3/12/2016
 Secreted
by parietal cells when stimulated
Fall 2012
by food
 Maintains stomach at pH of 1 to 4
 Secretion also stimulated by:
Large fatty meals
 Excessive amounts of alcohol
 Emotional stress

2
ACID-RELATED DISEASES
3/12/2016
 Caused

Fall 2012
by imbalance of the three cells of
the gastric gland and their secretions
 Most common: hyperacidity
 Lay terms for overproduction of HCl by the
parietal cells:
Indigestion, sour stomach, heartburn, acid
stomach
3
ACID-RELATED DISEASES (CONT’D)
3/12/2016
 Peptic
Fall 2012
ulcer disease (PUD)
 Gastroesophageal reflux disease (GERD)
 Helicobacter pylori (H. pylori)
Bacterium found in GI tract of 90% of patients
with duodenal ulcers and 70% of those with
gastric ulcers
 Can be detected by serum antibody tests
 Antibiotics are used to eradicate H. pylori

4
3/12/2016
TYPES OF ACID-CONTROLLING DRUGS
Antacids
 H2 antagonists
 Proton pump inhibitors
Fall 2012

5
ANTACIDS: MECHANISM OF ACTION
3/12/2016
 Neutralize
Fall 2012
stomach acid
 Promote gastric mucosal defense
mechanisms
 Secretion of:
Mucus: protective barrier against HCl
 Bicarbonate: helps buffer acidic properties of
HCl

6
3/12/2016
ANTACIDS: MECHANISM
OF ACTION (CONT’D)
DO NOT prevent the
overproduction of acid
 Antacids DO neutralize the acid once it is in
the stomach
Fall 2012
 Antacids
7
ANTACIDS: DRUG EFFECTS
3/12/2016

Fall 2012
Reduction of pain associated with acidrelated disorders
Raising gastric pH from 1.3 to 1.6 neutralizes
50% of the gastric acid
 Raising gastric pH 1 point (1.3 to 2.3)
neutralizes 90% of the gastric acid
 Reducing acidity reduces pain

8
ANTACIDS




formulations available as:
Capsules and tablets
Powders
Chewable tablets
Suspensions
Effervescent granules and tablets
Fall 2012

3/12/2016
 Over-the-counter
9
ANTACIDS (CONT’D)
alone or in combination
Fall 2012
Aluminum salts
 Magnesium salts
 Calcium salts
 Sodium bicarbonate

3/12/2016
 Used
10
ANTACIDS: ALUMINUM SALTS
Fall 2012
constipating effects
 Often used with magnesium to counteract
constipation
 Often recommended for patients with renal
disease (more easily excreted)
 Examples
3/12/2016
 Have
Aluminum carbonate: Basaljel
 Hydroxide salt: AlternaGEL
 Combination products (aluminum and magnesium):
Gaviscon, Maalox, Mylanta, Di-Gel

11
ANTACIDS: MAGNESIUM SALTS
Fall 2012
cause diarrhea; usually used
with other drugs to counteract this effect
 Dangerous when used with renal failure—
the failing kidney cannot excrete extra
magnesium, resulting in accumulation
3/12/2016
 Commonly
12
3/12/2016
ANTACIDS: MAGNESIUM
SALTS (CONT’D)
 Examples
Fall 2012

Hydroxide salt: magnesium hydroxide (Milk of
Magnesia)

Carbonate salt: Gaviscon (also a combination
product)

Combination products such as Maalox, Mylanta
(aluminum and magnesium)
13
ANTACIDS: CALCIUM SALTS

Fall 2012
forms, but carbonate is most common
 May cause constipation, kidney stones
 Also not recommended for patients with renal
disease—may accumulate to toxic levels
 Long duration of acid action—may cause
increased gastric acid secretion (hyperacidity
rebound)
 Often advertised as an extra source of dietary
calcium
3/12/2016
 Many
Example: Tums (calcium carbonate)
14
ANTACIDS: SODIUM BICARBONATE
Fall 2012
soluble
 Buffers the acidic properties of HCl
 Quick onset, but short duration
 May cause metabolic alkalosis
 Sodium content may cause problems in
patients with HF, hypertension, or renal
insufficiency
3/12/2016
 Highly
15
ANTACIDS AND ANTIFLATULENTS
Fall 2012
used to relieve the painful
symptoms associated with gas
 Several drugs are used to bind or alter
intestinal gas and are often added to
antacid combination products
3/12/2016
 Antiflatulents:
16
antiflatulents
Activated charcoal
 Simethicone

Fall 2012
 Over-the-counter
3/12/2016
ANTACIDS AND
ANTIFLATULENTS (CONT’D)
Alters elasticity of mucus-coated bubbles, causing
them to break
 Used often, but there are limited data to support
effectiveness

17
ANTACIDS: ADVERSE EFFECTS
and depend on the compound

Aluminum and calcium


Constipation
Magnesium


Fall 2012
used
3/12/2016
 Minimal,
Diarrhea
Calcium carbonate

Produces gas and belching; often combined with
simethicone
18
ANTACIDS: DRUG INTERACTIONS
Reduces the ability of the other drug to be
absorbed into the body
Fall 2012

of other drugs to antacids
3/12/2016
 Adsorption
 Chelation
Chemical binding, or inactivation, of another
drug
 Produces insoluble complexes
 Result: reduced drug absorption

19
 Increased
stomach pH
 Increased
Fall 2012
Increased absorption of basic drugs
 Decreased absorption of acidic drugs

3/12/2016
ANTACIDS: DRUG INTERACTIONS
(CONT’D)
urinary pH
Increased excretion of acidic drugs
 Decreased excretion of basic drugs

20
ANTACIDS: NURSING IMPLICATIONS
Fluid imbalances
 Renal disease
 GI obstruction
 Heart failure (HF)
 Pregnancy

Fall 2012
for allergies and preexisting conditions that
may restrict the use of antacids, such as:
3/12/2016
 Assess
 Patients
with HF or hypertension should not use
antacids with high sodium content
21
ANTACIDS: NURSING IMPLICATIONS
(CONT’D)
Fall 2012
with caution with other medications because
of the many drug interactions
 Most medications should be given 1 to 2 hours
after giving an antacid
 Antacids may cause premature dissolving of
enteric-coated medications, resulting in stomach
upset
3/12/2016
 Use
22
self-medication with antacids
may mask symptoms of serious underlying
diseases, such as cancer or bleeding ulcers
 If symptoms remain ongoing, patient should
seek medical evaluation
Fall 2012
 Long-term
3/12/2016
ANTACIDS: NURSING IMPLICATIONS
(CONT’D)
23
 Reduce




cimetidine (Tagamet)
nizatidine (Axid)
famotidine (Pepcid)
ranitidine (Zantac)
Fall 2012
acid secretion
 All available over the counter in lower dosage
forms
 Most popular drugs for treatment of
acid-related disorders
3/12/2016
HISTAMINE TYPE 2 (H2) ANTAGONISTS
24
histamine at the (H2) receptors of
acid-producing parietal cells
 Production of hydrogen ions is reduced,
resulting in decreased production of HCl
Fall 2012
 Block
3/12/2016
H2 ANTAGONISTS:
MECHANISM OF ACTION
25
H2 ANTAGONISTS: DRUG EFFECT
AND INDICATIONS
Suppressed acid secretion in the stomach
 Indications





Fall 2012

effect
3/12/2016
 Drug
GERD
PUD
Erosive esophagitis
Adjunct therapy to control upper GI bleeding
Pathologic gastric hypersecretory conditions
26
H2 ANTAGONISTS: ADVERSE EFFECTS
Fall 2012
very few adverse effects
 Cimetidine may induce impotence and
gynecomastia
 May cause headaches, lethargy, confusion,
diarrhea, urticaria, sweating, flushing, other
effects
3/12/2016
 Overall,
27
(Tagamet)
Binds with P-450 microsomal oxidase system in
the liver, resulting in inhibited oxidation of
many drugs and increased drug levels
 All H2 antagonists may inhibit the absorption of
drugs that require an acidic GI environment for
absorption

Fall 2012
 cimetidine
3/12/2016
H2 ANTAGONISTS: DRUG
INTERACTIONS
28
Smoking has been shown to decrease the
effectiveness of H2 blockers
Fall 2012

3/12/2016
H2 ANTAGONISTS: DRUG
INTERACTIONS (CONT’D)
29
H2 ANTAGONISTS:
NURSING IMPLICATIONS
3/12/2016
for allergies and impaired renal or
liver function
 Use with caution in patients who are
confused, disoriented, or elderly
 Take 1 hour before or after antacids
 For intravenous doses, follow
administration guidelines
Fall 2012
 Assess
30
PROTON PUMP INHIBITORS
Fall 2012
parietal cells release positive hydrogen
ions (protons) during HCl production
 This process is called the proton pump
 H2 blockers and antihistamines do not stop
the action of this pump
3/12/2016
 The
31
PROTON PUMP INHIBITORS:
MECHANISM OF ACTION
Fall 2012

3/12/2016
bind to H+/K+ ATPase enzyme
 This bond prevents the movement of
hydrogen ions from the parietal cell into the
stomach
 Results in achlorhydria—ALL gastric acid
secretion is temporarily blocked
 Irreversibly
To return to normal acid secretion, the parietal
cell must synthesize new H+/K+ ATPase
32
inhibition of gastric acid secretion
 lansoprazole (Prevacid)
Fall 2012
 Total
3/12/2016
PROTON PUMP INHIBITORS:
DRUG EFFECT
 omeprazole (Prilosec)
 rabeprazole (AcipHex)
 pantoprazole (Protonix) (IV form available)
 esomeprazole (Nexium)
33
maintenance therapy
 Erosive esophagitis
 Short-term treatment of active duodenal
and benign gastric ulcers
 Treatment of H. pylori–induced ulcers

Fall 2012
 GERD
3/12/2016
PROTON PUMP INHIBITORS:
INDICATIONS
Given with an antibiotic
34
for short-term therapy
 Some approved for long-term therapy
 Adverse effects uncommon
Fall 2012
 Safe
3/12/2016
PROTON PUMP INHIBITORS:
ADVERSE EFFECTS
35
PROTON PUMP INHIBITORS:
NURSING IMPLICATIONS
Fall 2012
for allergies and history of liver
disease
 Not all are available for parenteral
administration
 May increase serum levels of diazepam and
phenytoin; may increase chance for
bleeding with warfarin
3/12/2016
 Assess
36
 The
Fall 2012
granules of pantoprazole capsules may
be given via NG tubes, but the NG tube must be at
least 16 g or the tube may become clogged
3/12/2016
PROTON PUMP INHIBITORS:
NURSING IMPLICATIONS (CONT’D)
 Capsule
contents may be opened and
mixed with apple juice, but do not chew or crush
delayed-release granules
 Proton
pump inhibitors often work best
when taken 30 to 60 minutes before meals
37
OTHER DRUGS
Fall 2012
(Carafate)
misoprostol (Cytotec)
simethicone (Mylicon)
3/12/2016
sucralfate
38
SUCRALFATE (CARAFATE)
Fall 2012
drug
 Used for stress ulcers, peptic ulcer disease
 Attracted to and binds to the base of ulcers and
erosions, forming a protective barrier over these
areas
 Protects these areas from pepsin, which normally
breaks down proteins (making ulcers worse)
3/12/2016
 Cytoprotective
39
SUCRALFATE (CARAFATE) (CONT’D)
Fall 2012
absorption from the gut
 May cause constipation, nausea, and dry mouth
 May impair absorption of other drugs—give other
drugs at least 2 hours before sucralfate
 Do not administer with other medications
 Binds with phosphate; may be used in chronic
renal failure to reduce phosphate levels
3/12/2016
 Little
40
MISOPROSTOL (CYTOTEC)
Protect gastric mucosa from injury by
enhancing local production of mucus or
bicarbonate
 Promote local cell regeneration
 Help to maintain mucosal blood flow

Fall 2012
prostaglandin analog
 Prostaglandins have cytoprotective activity
3/12/2016
 Synthetic
41
MISOPROSTOL (CYTOTEC) (CONT’D)
Fall 2012
for prevention of NSAID-induced
gastric ulcers
 Doses that are therapeutic enough to treat
duodenal ulcers often produce abdominal
cramps, diarrhea
3/12/2016
 Used
42
SIMETHICONE
Fall 2012
drug
 Used to reduce the discomforts of gastric or
intestinal gas (flatulence)
 Alters elasticity of mucus-coated gas
bubbles, breaking them into smaller ones
 Result is decreased gas pain and increased
expulsion via mouth or rectum
3/12/2016
 Antiflatulent
43
3/12/2016
Bowel Disorder Drugs
Fall 2012
44
Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.
DIARRHEA
Fall 2012
Abnormal passage of stools with increased
frequency, fluidity, and weight, or with
increased stool water excretion
3/12/2016

45
DIARRHEA (CONT’D)
3/12/2016
Fall 2012
Acute diarrhea
 Sudden onset in a previously healthy person
 Lasts from 3 days to 2 weeks
 Self-limiting
 Resolves without sequelae
46
DIARRHEA (CONT’D)
3/12/2016
Fall 2012
Chronic diarrhea
 Lasts for more than 3 weeks
 Associated with recurring passage of
diarrheal stools, fever, loss of appetite,
nausea, vomiting, weight loss, and chronic
weakness
47
CAUSES OF DIARRHEA
Fall 2012
Chronic Diarrhea
Tumors
Diabetes mellitus
Addison’s disease
Hyperthyroidism
Irritable bowel syndrome
AIDS
3/12/2016
Acute Diarrhea
Bacterial
Viral
Drug induced
Nutritional factors
Protozoa
48
Fall 2012
Adsorbents
 Coat the walls of the GI tract
 Bind to the causative bacteria or toxin,
which is then eliminated through the stool
 Examples: bismuth subsalicylate (PeptoBismol), activated charcoal, aluminum
hydroxide, others
3/12/2016
ANTIDIARRHEALS:
MECHANISM OF ACTION
49
Fall 2012
Antimotility drugs: anticholinergics
 Decrease intestinal muscle tone and
peristalsis of GI tract
 Result: slows the movement of fecal matter
through the GI tract
 Examples: belladonna alkaloids (atropine,
hyoscyamine)
3/12/2016
ANTIDIARRHEALS:
MECHANISM OF ACTION (CONT’D)
50
ANTIDIARRHEALS:
MECHANISM OF ACTION (CONT’D)
3/12/2016
Fall 2012
Antimotility drugs: opiates
 Decrease bowel motility and relieve rectal spasms
 Decrease transit time through the bowel, allowing
more time for water and electrolytes to be
absorbed
 Reduce pain by relief of rectal spasms
 Examples: paregoric, opium tincture, codeine,
loperamide (over the counter), diphenoxylate
51
ANTIDIARRHEALS:
MECHANISM OF ACTION (CONT’D)

Fall 2012

3/12/2016
Intestinal flora modifiers
 Probiotics or bacterial replacement drugs
 Bacterial cultures of Lactobacillus organisms
work by:
Supplying missing bacteria to the GI tract
Suppressing the growth of diarrhea-causing bacteria
 Example:
L. acidophilus (Lactinex)
52
ANTIDIARRHEALS:
ADVERSE EFFECTS
3/12/2016
Fall 2012
Adsorbents
 Increased bleeding time
 Constipation, dark stools
 Confusion, twitching
 Hearing loss, tinnitus, metallic taste, blue
gums
53
ANTIDIARRHEALS:
ADVERSE EFFECTS (CONT’D)
3/12/2016
Fall 2012
Anticholinergics
 Urinary retention, hesitancy, impotence
 Headache, dizziness, confusion, anxiety,
drowsiness, confusion
 Dry skin, flushing
 Blurred vision
 Hypotension, bradycardia
54
Fall 2012
Opiates
 Drowsiness, sedation, dizziness, lethargy
 Nausea, vomiting, anorexia, constipation
 Respiratory depression
 Hypotension
 Urinary retention
 Flushing
3/12/2016
ANTIDIARRHEALS:
ADVERSE EFFECTS (CONT’D)
55
ANTIDIARRHEALS: INTERACTIONS
Fall 2012
decrease the absorption of many
drugs, including digoxin, clindamycin, quinidine,
hypoglycemic drugs, others
 Adsorbents cause increased bleeding time and
bruising when given with anticoagulants
 Antacids can decrease effects of anticholinergic
antidiarrheal drugs
 Many other interactions
3/12/2016
 Adsorbents
56
thorough history of bowel patterns,
general state of health, and recent history of
illness or dietary changes; assess for allergies
Fall 2012
 Obtain
3/12/2016
ANTIDIARRHEALS:
NURSING IMPLICATIONS
 Do
NOT give bismuth subsalicylate to children or
teenagers with chickenpox or influenza because of
the risk of Reye’s syndrome
57
adsorbents carefully in elderly patients or
those with decreased bleeding time, clotting
disorders, recent bowel surgery, confusion
Fall 2012
 Use
3/12/2016
ANTIDIARRHEALS:
NURSING IMPLICATIONS (CONT’D)
 Do
not administer anticholinergics to patients with
a history of narrow-angle glaucoma, GI
obstruction, myasthenia gravis, paralytic ileus, and
toxic megacolon
58
CONSTIPATION
Fall 2012
infrequent and difficult passage
of feces through the lower GI tract
 Symptom, not a disease
 Disorder of movement through the colon
and/or rectum
 Can be caused by a variety of diseases
or drugs
3/12/2016
 Abnormally
59
LAXATIVES
Fall 2012
forming
 Emollient
 Hyperosmotic
 Saline
 Stimulant
 Peripherally acting opioid antagonists
3/12/2016
 Bulk
60
LAXATIVES: MECHANISM OF ACTION
3/12/2016
Fall 2012
Bulk forming
 High fiber
 Absorb water to increase bulk
 Distend bowel to initiate reflex bowel
activity
 Examples:
psyllium (Metamucil)
 methylcellulose (Citrucel)

61
Stool softeners: docusate salts (Colace, Surfak)
 Lubricants: mineral oil
Fall 2012
Emollient
 Stool softeners and lubricants
 Promote more water and fat in the stools
 Lubricate the fecal material and intestinal
walls
 Examples:
3/12/2016
LAXATIVES: MECHANISM OF ACTION
(CONT’D)

62
Fall 2012
Hyperosmotic
 Increase fecal water content
 Results in bowel distention, increased
peristalsis, and evacuation
 Examples:
3/12/2016
LAXATIVES: MECHANISM OF ACTION
(CONT’D)
Polyethylene glycol (PEG)
 Sorbitol, glycerin
 Lactulose (also used to reduce elevated serum
ammonia levels)

63
Magnesium hydroxide (Milk of Magnesia)
 Magnesium citrate (Citroma)
Fall 2012
Saline
 Increase osmotic pressure within the
intestinal tract, causing more water to enter
the intestines
 Results in bowel distention, increased
peristalsis, and evacuation
 Examples:
3/12/2016
LAXATIVES: MECHANISM OF ACTION
(CONT’D)

64
LAXATIVES: MECHANISM OF ACTION
(CONT’D)
3/12/2016
Fall 2012
Stimulant
Increases peristalsis via intestinal nerve
stimulation
Examples:
 senna (Senekot)
 bisacodyl (Dulcolax)
65
PERIPHERALLY ACTING OPIOID
ANTAGONISTS
Fall 2012
of constipation related to opioid use
and bowel resection therapy
 Block entrance of opioid into bowel
 Strict regulations for use
 Allow bowel to function normally with continued
opioid use
3/12/2016
 Treatment
methylnaltrexone (Relistor)
 alvimopan (Entereg)

66
LAXATIVES: INDICATIONS
Bulk forming
Acute and chronic
constipation, irritable
syndrome, diverticulosis
bowel
Emollient
Fall 2012
Use
3/12/2016
Laxative Group
Acute and chronic
constipation, fecal
impaction
Facilitation of BMs in
anorectal conditions
67
LAXATIVES: INDICATIONS (CONT’D)
Saline
Constipation
Diagnostic and surgical
preps
Fall 2012
Use
Chronic constipation
Diagnostic and surgical
preps
3/12/2016
Laxative Group
Hyperosmotic
68
LAXATIVES: INDICATIONS (CONT’D)
Fall 2012
Use
Acute constipation
Diagnostic and surgical
preps
3/12/2016
Laxative Group
Stimulant
69
LAXATIVES: ADVERSE EFFECTS
3/12/2016
Fall 2012
Bulk forming
 Impaction
 Fluid overload
 Electrolyte imbalances
 Esophageal blockage
 Emollient
 Skin rashes
 Decreased absorption
of vitamins
 Electrolyte imbalances
 Lipid pneumonia

70
LAXATIVES: ADVERSE EFFECTS (CONT’D)
Hyperosmotic

Abdominal bloating
Electrolyte imbalances
Rectal irritation
Fall 2012



3/12/2016

Saline





Magnesium toxicity (with renal insufficiency)
Cramping
Electrolyte imbalances
Diarrhea
Increased thirst
71
LAXATIVES: ADVERSE EFFECTS (CONT’D)
Stimulant
Nutrient malabsorption

Skin rashes

Gastric irritation

Electrolyte imbalances

Discolored urine

Rectal irritation
 All
Fall 2012

3/12/2016

laxatives can cause electrolyte imbalances!
72
LAXATIVES: NURSING IMPLICATIONS
Fall 2012
patients not to take a laxative or
cathartic if they are experiencing nausea,
vomiting, and/or abdominal pain
3/12/2016
 Inform
73
LAXATIVES: NURSING IMPLICATIONS
(CONT’D)
Fall 2012
healthy, high-fiber diet and increased
fluid intake should be encouraged as an
alternative to laxative use
 Long-term use of laxatives often results in
decreased bowel tone and may lead to
dependency
3/12/2016
A
74
should take all laxative tablets
with 6 to 8 ounces of water
Fall 2012
 Patients
3/12/2016
LAXATIVES: NURSING IMPLICATIONS
(CONT’D)
 Patients
should take bulk-forming
laxatives as directed by the manufacturer
with at least 240 mL (8 ounces) of water
75
 Give
 Monitor
Fall 2012
bisacodyl with water because of interactions
with milk, antacids, and juices
3/12/2016
LAXATIVES: NURSING IMPLICATIONS
(CONT’D)
for therapeutic effect
76
3/12/2016
Antiemetic and Antinausea Drugs
Fall 2012
77
Mosby items and derived items © 2011, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.
DEFINITIONS
3/12/2016
 Nausea
Unpleasant feeling that often precedes
vomiting
 Emesis

(vomiting)
Forcible emptying of gastric, and occasionally,
intestinal contents
 Antiemetic

Fall 2012

drugs
Used to relieve nausea and vomiting
78
center (VC)
 Chemoreceptor trigger zone (CTZ)
Fall 2012
 Vomiting
3/12/2016
VOMITING CENTER AND
CHEMORECEPTOR TRIGGER ZONE
Both located in the brain
 Once stimulated, cause the vomiting reflex

79
3/12/2016
Fall 2012
80
different mechanisms of action
 Most work by blocking one of the vomiting
pathways, thus blocking the stimulus that
induces vomiting
Fall 2012
 Many
3/12/2016
ANTIEMETICS AND ANTINAUSEA
DRUGS: MECHANISM OF ACTION
81
3/12/2016
Fall 2012
82
INDICATIONS
Fall 2012
indications vary per class of
antiemetics
 General use for each type: prevention and
reduction of nausea and vomiting
3/12/2016
 Specific
83
 Anticholinergic
drugs (ACh blockers)

Fall 2012
Bind to and block acetylcholine (ACh) receptors
in the inner ear labyrinth
 Block transmission of nauseating stimuli to CTZ
 Also block transmission of nauseating stimuli
from the reticular formation to the VC
 Scopolamine

3/12/2016
MECHANISM OF ACTION AND
OTHER INDICATIONS
Also used for motion sickness (transdermal patch)
84
MECHANISM OF ACTION AND
OTHER INDICATIONS (CONT’D)





Inhibit ACh by binding to H1 receptors
Prevent cholinergic stimulation in vestibular and
reticular areas, thus preventing nausea and
vomiting
Also used for motion sickness, nonproductive
cough, allergy symptoms, sedation
dimenhydrinate (Dramamine)
diphenhydramine (Benadryl)
meclizine (Antivert)
Fall 2012

drugs (H1 receptor blockers)
3/12/2016
 Antihistamine
85
MECHANISM OF ACTION AND
OTHER INDICATIONS (CONT’D)





Block dopamine receptors on the CTZ
Also used for psychotic disorders, intractable
hiccups
prochlorperazine (Compazine)
promethazine (Phenergan)
droperidol (Inapsine): Use is controversial
because of associated cardiac dysrhythmia
Others
Fall 2012

drugs
3/12/2016
 Antidopaminergic
86
MECHANISM OF ACTION AND
OTHER INDICATIONS (CONT’D)




Block dopamine in the CTZ
Cause CTZ to be desensitized to impulses it
receives from the GI tract
Also stimulate peristalsis in GI tract, enhancing
emptying of stomach contents
Also used for GERD, delayed gastric emptying
metoclopramide (Reglan)

Fall 2012

drugs
3/12/2016
 Prokinetic
Long-term use may cause irreversible tardive
dyskinesia
87
MECHANISM OF ACTION AND
OTHER INDICATIONS (CONT’D)





Block serotonin receptors in the GI tract, CTZ,
and VC
Used for nausea and vomiting in patients
receiving chemotherapy and for postoperative
nausea and vomiting
dolasetron (Anzemet)
granisetron (Kytril)
ondansetron (Zofran)
palonosetron (Aloxi)
Fall 2012

blockers
3/12/2016
 Serotonin
88
Major psychoactive substance in marijuana
 Inhibitory effects on reticular formation,
thalamus, cerebral cortex
 Alter mood and body’s perception of its
surroundings

Fall 2012
 Tetrahydrocannabinoids
3/12/2016
MECHANISM OF ACTION AND
OTHER INDICATIONS (CONT’D)
89
(cont’d)
dronabinol (Marinol)
 Used for nausea and vomiting associated with
chemotherapy, and anorexia associated with
weight loss in AIDS patients

Fall 2012
 Tetrahydrocannabinoids
3/12/2016
MECHANISM OF ACTION AND
OTHER INDICATIONS (CONT’D)
90
ADVERSE EFFECTS
Fall 2012
according to drug used
 Stem from their nonselective blockade of
various receptors
3/12/2016
 Vary
91
HERBAL PRODUCTS: GINGER

Fall 2012
for nausea and vomiting including that
caused by chemotherapy, morning sickness,
and motion sickness
 Adverse effects
3/12/2016
 Used
Anorexia, nausea and vomiting, skin reactions
 Drug
interactions
May increase absorption of oral medications
 Increase bleeding risk with anticoagulants

92
NURSING IMPLICATIONS (CONT’D)
Fall 2012
of these drugs cause severe
drowsiness; warn patients about driving or
performing any hazardous tasks
 Taking antiemetics with alcohol may cause
severe CNS depression
 Teach patients to change position slowly to
avoid hypotensive effects
3/12/2016
 Many
93
NURSING IMPLICATIONS (CONT’D)
Fall 2012
chemotherapy, antiemetics are often
given 30 to 60 minutes before
chemotherapy begins
 Monitor for therapeutic effects
 Monitor for adverse effects
3/12/2016
 For
94