GI Agents: Diarrhea, Constipation, N/V, GERD Flashcards
(209 cards)
1
Q
Causes of constipation?
A
Low fiber diet, Low fluid intake, Inactivity, Aging, Diseases (IBS, DM, Hypothyroidism, MS, Parkinson’s, Anxiety, Depression, Cancer), Meds
2
Q
Meds that can cause constipation?
A
Opioids, CCBs, Anticholinergics (TCAs, diphenhydramine, atypical antipsychotics), Paroxetine, Calcium supplements, Antacids w/ aluminum or calcium, Thiazides, NSAIDs
3
Q
Goals of therapy for constipation?
A
-Increase frequency of BMs
-Titrate dose to soften stool
-Prevent recurrence
4
Q
Non-pharmalogical tx for constipation?
A
-Hydration (8-12 glasses/day)
-Balanced diet (soluble fiber in food): apples, oranges, peas
-Exercise (walking, swimming)
-D/C meds that cause constipation
5
Q
1st line treatment for constipation?
A
OTC laxatives
6
Q
Targeted constipation therapy can be specific to which diagnoses?
A
Chronic idiopathic constipation, IBS-C, Opioid induced
7
Q
Laxatives for constipation?
A
Stool softeners, Lubricants, Fiber/Bulk agents, Osmotics, Stimulants
8
Q
Stool softeners for constipation?
A
Docusate sodium (Colace)
9
Q
Libricants for constipation?
A
Mineral oil
10
Q
Fiber/Bulk agents for constipation?
A
Psyllium (Metamucil), Methylcellulose (Citrucel)
11
Q
Osmotics for constipation?
A
Glycerin, Lactulose, Sorbitol, Polyethylene glycol (PEG) (Miralax), Saline laxatives
12
Q
Stimulants for constipation?
A
Bisacodyl (Dulcolax), Senna (Senokot)
13
Q
MOA of Docusate?
A
Surfactant that lowers surface tension of stool (water penetrates, hydrates, and softens stool)
14
Q
ROA of Docusate?
A
PO
15
Q
Onset of Docusate?
A
1-3 days
16
Q
Use for Docusate?
A
Avoid strain, preventative
Post-MI, surgery, hemorrhoids flare, combo w/ other meds for opioid induced
*doesn’t get bowels moving if already constipated
17
Q
Precautions w/ using Docusate?
A
Efficacy is questionable (evidence low)
18
Q
Special populations for Docusate use?
A
Popular w/ older adults, pregnancy, kids
19
Q
Contraindications of Docusate?
A
Mineral oil (docusate inc. mineral oil absorption)
20
Q
Mineral oil MOA?
A
Softens stool/lubricates lining of gut to facilitate defecation
21
Q
ROA of Mineral oil?
A
PO
22
Q
Onset of Mineral oil?
A
6-8 hrs
23
Q
Use for Mineral oil?
A
Occasional constipation
24
Q
Precautions with Mineral oil?
A
Avoid long-term use, bedridden pts (aspiration pneumonia), decreases absorption of fat-soluble vitamins
AVOID IN: kids, elderly, pregnacy
25
Contraindications of Mineral oil?
Docusate (increases absorption of mineral oil)
26
MOA of fiber/bulk agents for constipation?
Holds water in stool, adds bulk, promotes peristalsis
27
ROA for fiber/bulk agents?
PO
28
Onset of fiber/bulk agents?
1-3 days
29
Use of fiber/bulk agents?
Daily, dietary
30
Precautions w/ fiber/bulk agents?
Need a lot of fluids & movement (Do not use if bedridden/fluid limitations)
31
Side effects of fiber/bulk agents?
Bloating/cramps
32
Drug interactions w/ fiber/bulk agents?
Separate other meds by 1-2hrs
33
Special populations use of fiber/bulk agents?
Older adults must continue to drink & move around, pregnancy needs plenty of water, limited role for opioid induced
34
MOA of glycerin?
Local rectal stimulation: induces evacuation
35
ROA of glycerin?
Rectal suppository
36
Onset of glycerin?
quick action
37
Special populations use of glycerin?
Suppository sizes for kids/infants/adults, common use in children, can be used in pregnancy
38
MOA of lactulose, sorbitol (osmotic laxatives)?
Non-absorbable sugars that pull water into colon lumen & promote peristalsis
39
ROA of lactulose, sorbitol (osmotic laxatives)?
Oral, rectal
40
Onset of lactulose, sorbitol (osmotic laxatives)?
12hrs to 3 days
41
Use of lactulose, sorbitol (osmotic laxatives)?
Prevent & treat chronic constipation, daily use not recommended
42
Precautions with lactulose, sorbitol (osmotic laxatives)?
Electrolyte imbalance, DM (high amnt of lactose)
43
Frequency of osmotic laxatives?
Daily
44
MOA of Polyethylene glycol (Miralax) and PEG 3350 (GoLYTELY) (osmotic laxatives)?
Non-absorbable osmotic sugar that draws water into colon lumen but also contains electrolytes (prevents electrolyte shifts into colon)
45
ROA of Polyethylene glycol (Miralax) and PEG 3350 (GoLYTELY) (osmotic laxatives)?
PO
46
Use for Polyethylene glycol (Miralax) and PEG 3350 (GoLYTELY) (osmotic laxatives)?
Prevention/tx post MI, surgery, opioid induced (mix w water)
onset 1-3 days
47
Which laxative is used for colonic cleansing prior to diagnostics?
GoLYTELY (1 gallon jug) w/ watery evacuation in 1-6 hrs
48
Precautions w/ Polyethylene glycol (Miralax) and PEG 3350 (GoLYTELY) (osmotic laxatives)?
Cramping, diarrhea (but less than other laxatives)
49
Special populations use of Polyethylene glycol (Miralax) and PEG 3350 (GoLYTELY) (osmotic laxatives)?
Use in all ages, 1st line in hospitals for pregnancy
50
Saline laxatives?
Magnesium hydroxide (milk of mag), Magnesium citrate, Sodium phosphate
51
MOA of saline laxatives?
Non-absorbable salts that pull fluid into colon to promote peristalsis
52
ROA for saline laxatives?
PO
(sodium phosphate is also an enema)
53
Onset of MOM?
30 min - 8 hr
54
Onset of Mag. citrate?
30 min - 6 hr
55
Onset of PO Sodium phos.?
1-3 hr
56
Onset of Sodium phos. enema (Fleets enema)?
1-5 min
57
Use of saline laxatives?
Occasional use (every few weeks), avoid use on regular basis
58
Precautions w/ saline laxatives?
Cramps, dehydration, diarrhea, electrolyte imbalance
59
Special populations use of saline laxatives?
Caution dehydration, renal, cardiac
60
Stimulant laxatives?
Bisacodyl (Dulcolax) and Senna (Senokot)
61
MOA of stimulant laxatives?
Local mucosal irritation directly stimulates GI tract
62
Onset of stimulant laxatives?
PO: 6-12 hrs
Rectal: 15-60 min
63
Use of stimulant laxatives?
Tx and prevention: quick action
-can be used for opioid induced
64
Precautions w/ stimulant laxatives?
Cramping
65
Special populations use w/ stimulant laxatives?
Pts on chronic constipation meds, safe for older adults, no evidence that long-term use is harmful
66
Opioid induced constipation prevalence (cancer pts and non cancer pts w/ pain)?
Cancer pain 95%
Nonmalignant pain 80%
67
Which opioids can be constipating?
All
68
Does tolerance to opioid constipation develop?
Rarely
69
Laxatives for opioid induced constipation?
Senna, PEG
70
Pathophysiology of opioid induced constipation (OIC)?
Decrease Gi motility, increase absorption of fluid in gut, decrease intestinal excretions, decrease defecation reflex
(Result of u-opioid R's in GI tract)
71
Target therapy recommendations by the AGA for OIC?
Recommended: Peripherally acting mu-opioid R antagonists (PAMORAs)
No recommendations: Intestinal secretagogues, Selective 5-HT agonists
72
Recommendations for PAMORAs?
Naldemedine (Symporic) PO: Strong rec.
Naloxegol (Movantik) PO: Strong rec.
Methylnatrexone (Relistor) PO or SubQ: conditional rec.
73
MOA for PAMORAs?
Block opioid from binding at mu R's in GI tract --> inhibits delay in GI transit time, decreasing constipation effects of opioids
74
2nd line for OIC after laxatives fail?
PAMORAs
75
Administration of Naloxegol (Movantik)?
Empty stomach (1-2 hrs after first meal)
D/c all other laxatives (may re-initiate if suboptimal response after 3 days)
76
Onset of Naloxegol (Movantik)?
6-12 hrs up to 3 days
77
Avoid what food with Naloxegol (Movantik)?
Grapefruit (and juice)
78
Use of Naloxegol (Movantik)?
OIC in adults w/ noncancer pain
(off label for cancer pain OIC)
79
Caution w/ use of Naloxegol (Movantik)?
Severe abdominal pain, diarrhea (may result in hosp)
80
Dose adjustments for Naloxegol (Movantik)?
Renal dose adjustment
Avoid use in hepatic impairment
81
Metabolism of Naloxegol (Movantik)?
CYP3A4 (many d/d interactions)
82
Administration of Naldemedine (Symproic)?
w/ or w/o food
83
Onset of Naloxegol (Movantik)?
w/in 24 hrs
84
Use of Naloxegol (Movantik)?
OIC in adults w/ noncancer pain
85
Avoid use of Naloxegol (Movantik) with what?
Severe hepatic impairment
86
Metabolism of Naloxegol (Movantik)?
CYP3A4 (many d/d interactions)
87
Administration of Methylnatrexone (Relistor)?
PO empty stomach
SubQ rotate between upper arm, abdomen, thigh
88
Use of Methylnatrexone (Relistor)?
PO: OIC in noncancer pts
SubQ: OIC in both cancer/noncancer
89
Onset of Methylnatrexone (Relistor)?
w/in 4 hrs
90
What causes diarrhea?
Imbalance between water absorption/secretion in GI tract
91
3 types of diarrhea?
Acute: resolves in 14 days (mostly aquired: viral or travelers: bacterial/viral)
Persistent: 14-30 days
Chronic: >30 days (IBD, IBs-D, Diabetic neuropathy)
92
Oral rehydration in community acquired diarrhea?
Water, juice, sports drinks, soups, salty crackers, pedialyte
93
Are probiotics recommended in community acquired diarrhea?
Not unless post-abx diarrhea
94
Meds for community acquired diarrhea?
Bismuth subsalicylate and Loperamide
95
Travelers diarrhea prophylaxis?
Bismuth, Abx, Probiotics
96
Tx of travelers diarrhea?
Rehydration, Bismuth, Loperamide, Abx
97
Meds that may cause diarrhea?
Acid-reducing agents (PPIs, cimetidine), Misoprostol, Antacids w/ Mg, Colchicine, Digoxin, NSAIDs, Quinidine, Antiretroviral, Abx (Clindamycin, Erythromycin, Augmentin), Chemo (5FU), AntiHTN (ACEis), Laxatives
98
Goals of tx for diarrhea?
Identify causes, Sx relief, Correct fluid-electrolyte loss, Manage diet,
**stopping diarrhea not necessarily goal (esp C. diff) --> need to rid pathogens or toxin
99
Non-pharmacologic tx for diarrhea?
-Diet: low residue if tolerable, avoid salty/spicy/caffeine/dairy, replenish fluids/electrolytes, inc. diet as tolerable
-BRAT diet (banana, rice, applesauce, toast): low cal/protein/fat
-Hold laxatives/other contributing meds
100
Agents for diarrhea?
Antimotility, Antispasmodics, Antisecretory/Adsorbents, Probiotics
101
Antimotility agents for diarrhea?
Loperamide (Imodium) OTC, Diphenoxylate w/ atropine (Lomotil) Rx
102
MOA of antimotility agents for diarrhea?
Stimulate mu R's on intestinal muscles, reduce intestinal motility, inc. intestinal absorption, reduce fecal volume
103
Use of antimotility agents for diarrhea?
Most effective in acute diarrhea
104
Precautions w/ antimotility agents for diarrhea?
C/I in bloody & infectious diarrhea
High doses cross BBB
Addiction potential (atropine in Lomotil is to reduce risk of abuse)
105
Special population use of antimotility agents for diarrhea?
Not for kids <2y/o, weight-based dosing in kids up to 12y/o
106
US boxed warning in antimotility agents for diarrhea?
QT prolongation
107
Antispasmodic agent for diarrhea?
Dicyclomine (Bentyl)
108
MOA of Dicyclomine (Bentyl) for diarrhea?
Anticholinergic- blocks action of ACh at sites in GI smooth muscle (reduces spasms)
109
Use of Dicyclomine (Bentyl) for diarrhea?
IBS-D or abdominal pain
110
Side effects of Dicyclomine (Bentyl) for diarrhea?
Constipation, drowsiness, blurred vision, anti SLUD: salivation, lacrimation, urination, defecation (Anticholinergic)
111
Antisecretory/Adsorbent agent for diarrhea?
Bismuth subsalicylate (Pepto)
112
MOA of Bismuth subsalicylate (Pepto) for diarrhea?
Dec. secretions, absorbs bacteria/toxins/fluids, dec. stool liquidity and frequency
113
Use of subsalicylate (Pepto) for diarrhea?
Acute diarrhea, traveler's diarrhea
114
Precautions w/ subsalicylate (Pepto) for diarrhea?
Can blacken tongue and stool (harmless), may reduce absorption of some meds
115
Probiotic bacteria for diarrhea?
Lactic-acid producing bacteria (bifidobacteria & lactobacilli, yeast- Saccharomyces)
116
Which probiotics have bifidobacteria?
Activia yogurt, Align
117
Which probiotics have lactobacilli?
Culturelle, Kefir, Lactinex
118
Which probiotics have Saccharomyces (yeast)?
Florastor
119
MOA of probiotics for diarrhea?
Recolonize gut w beneficial microbes
120
Use of probiotics for diarrhea?
Possible prevention/tx of abx associated diarrhea/ C. diff
Possible prevention of travelers, daycare diarrhea
121
Which cells in the stomach secrete gastric acid?
Parietal cells
122
What are the 3 R's on the parietal cell that are stimulated by smell or ingestion of food?
Histamine**, Gastrin, Acetylcholine R's
123
Stimulation of histamine, gastrin, and ACh R's results in what?
Activation of cAMP, stimulating acid secretion by H+/K+ ATPase pump (Proton pump)
124
H+ and Cl- combine in the blood to form what?
Hydrochloric acid (HCl)
125
What is GERD?
Retrograde passage of gastric contents from stomach into esophagus (primarily d/t LES relaxation, also inc. gastric pressure and delayed gastric emptying time)
*inflammation results from chronic exposure of mucosa to gastric acid
126
GERD Risk Factors?
Alc, Smoking, Caffeine, Obesity, Pregnancy, Drugs, Foods (chocolate, peppermint, high fat, citric acid, tomato, spicy, large meals)
127
Meds that are risk factors of GERD?
Bisphosphonates, CCBs, Iron, Potassium, NSAIDs
128
Sx of GERD?
Heartburn (common at night, certain foods, may radiate to neck), Belching, Chronic cough, Hoarseness, Dental erosion, Angina
129
Self care for GERD (occasional sx)?
Antacids, OTC H2's or PPI's
130
Tx for persistent sx w/ diagnosed GERD?
PPI's, H2 antagonists, Antacids
131
Antacids for GERD?
Ca, Mg, Aluminum based (Mylanta, Maalox, Tums, Rolaids)
132
MOA of antacids for GERD?
Neutralize acid, raises intragastric pH
133
Onset of antacids?
10 min, short duration (1-2 hr)
134
Adverse effects of antacids?
Ca and aluminum: constipation
Mg: diarrhea
135
D/d interactions of antacids?
Chelation (binding) to fluoroquinolones, Increase of pH and reduction of absorption of Itraconazole and Iron
136
H2 blockers for GERD?
Cimetidine, Ranitidine, Nizatidine, Famotidine (most potent)
137
MOA od H2 blockers for GERD?
Compete w/ H2 R's on parietal cells (suppress acid secretion)
138
ROA of H2 blockers for GERD?
PO (PRN)
139
Use of H2 blockers for GERD?
Good for sx relief/prevention of: GERD, PUD (not H-pylori related), Dyspepsia, Stress related gastritis
*most effective in reducing nocturnal acid
140
Drug interactions of H2 blockers for GERD?
Inhibits 2C9, 2D6, 3A4
Increases levels of: Warfarin, Phenytoin, Diazepam, Propanolol
**Cimetidine most
141
Minimal adverse effects of H2 blockers for GERD?
Headache, dizzy, diarrhea, constipation
142
Special populations use of H2 blockers for GERD?
Require dose adjustment in mod-severe renal impairment
Avoid if high risk of delirium (beers)
143
Limitations of H2 blockers for GERD?
Tolerance may develop, not effective w/ H. pylori, Less potent than PPIs
144
PPIs for GERD?
OTC: Omeprazole, Pantoprazole, Lansoprazole, Esomeprazole
Rx: Dexlansoprazole, Rabeprazole
145
MOA of PPIs?
Prodrug, pass into parietal cells, protonated and inhibit protein pump
146
ROA of PPIs for GERD?
IV (pantoprazole), PO (all) - most 30-60 min before food
147
Use of PPIs for GERD?
More effective than H2 blockers for suppression of acid secretion: GERD, PUD (H. pylori), Dyspepsia, Stress ulcer prophylaxis
148
Precautions of PPIs?
-May inc. risk of osteoporosis/fractures if chronic use
-May dec oral absorption of Mg and B12 if chronic use
-May inc. risk of infections (disrupt acid barrier, C.diff, beers list)
-Respiratory CAP
-Difficult to d/c (suggest taper over few wks, reduce dose, every other day)
149
Adverse effects of PPIs?
Diarrhea, abd pain, nausea, headache
150
Drug interactions w/ PPIs?
Inhibits CYP2C19: (strong-Omeprazole/Esomeprazole) will convert Clopidogrel to active metabolite (pantoprazole better w/ clopidogrel)
Inhibits other meds needing acidic environment: Iron, Itraconazole, Atazanavir)
151
Pathophysiology of N/V?
Vomit center in CNS receives signal from other areas of brain/GI tract by chemoreceptor trigger zone (CTZ) --> stimulates vomit center by NT
152
NT that trigger CTZ in chemo-induced N/V?
Serotonin- 5HT3, Substance P Neurokinin NK1, Dopamine D2
153
NT that trigger CTZ in vertigo, motion sickness N/V?
Acetylcholine, Histamine H1
154
Med that helps w/ anxiety of chemo-induced N/V?
Benzodiazepines
155
Target NT antagonists for Chemo-induced N/V?
5-HT3 antagonists, NK-1 antagonists, Dopamine antagonists
156
Aids in target NT antagonists for Chemo-induced N/V?
Corticosteroids (Dexamethasone), Olanzapine
157
RF for chemo-induced N/V?
Specific chemo agents, young>older, women>men, hx of motion sickness/morning sickness
158
Phases of chemo-induced N/V?
-Acute: 0-24 hrs post therapy
-Delayed (late): >24hrs
-Anticipatory: before new cycle in response to conditional stimuli (starts after 3-4 cycles)
-Breakthrough: w/in 5 days of prophylactic antiemetic use, requires rescue
159
Chemo emetic high risk (>90% chance w/ Cisplastin Cyclophosphamide) category recommended therapy?
3 or 4 drug combo: NK1 antagonist + 5-HT3 antagonist + corticosteroid +/- olanzapine
160
Chemo emetic moderate risk (30-90%) category recommended therapy?
2 or 3 drug combo: 5-HT3 antagonist + corticosteroid +/- olanzapine
161
Chemo emetic low risk (10-30%) category recommended therapy?
Monotherapy: 5-HT3 antagonist or Dopamine antagonist or Dexamethasone
162
Chemo emetic minimal risk (<10%) category recommended therapy?
No prophylaxis
163
Serotonin (5-HT3) antagonists for chemo-related N/V?
Ondansetron, Alosetron, Granisetron, Dolasetron, Palonosteron
164
MOA of Serotonin (5-HT3) antagonists for chemo-related N/V?
Blocks 5-HT3 R's
165
ROA of Serotonin (5-HT3) antagonists for chemo-related N/V?
All available PO or IV
166
Use of Serotonin (5-HT3) antagonists for chemo-related N/V?
Acute>delayed (most effective in first 24hrs)
167
Side effects of Serotonin (5-HT3) antagonists for chemo-related N/V?
Constipation, mild headache
168
Precautions of Serotonin (5-HT3) antagonists for chemo-related N/V?
QT prolongation, serotonin syndrome
169
Drug interactions w/ Serotonin (5-HT3) antagonists for chemo-related N/V?
Substrate of CYP3A4 (major)
170
Special populations considerations with Serotonin (5-HT3) antagonists for chemo-related N/V?
Caution w/ risk of arrhythmia
171
Substance P/Neurokinin R (NK-1) Antagonists for chemo-induced N/V?
Aprepitant (PO), Fosaprepitant (IV), Rolapitant (PO)
172
MOA of Substance P/Neurokinin R (NK-1) Antagonists for chemo-induced N/V?
Antagonizes Substance P/Neurokinin (NK-1) R's
173
Use of Substance P/Neurokinin R (NK-1) Antagonists for chemo-induced N/V?
Prevention of acute & delayed N/V
-3 day regimen in combo for highly-emetic chemo (not very effective alone)
174
Side effects of Substance P/Neurokinin R (NK-1) Antagonists for chemo-induced N/V?
Fatigue, dizzy, diarrhea
175
Precautions w/ Substance P/Neurokinin R (NK-1) Antagonists for chemo-induced N/V?
Hypersensitivity rxn during IV infusion
176
Drug interactions of Substance P/Neurokinin R (NK-1) Antagonists for chemo-induced N/V?
Many (CYP3A4 substrate), induces CYP2C9 (warfarin)
177
Corticosteroids for chemo-induced N/V?
Dexamethasone, Methylprednisolone
178
MOA of Corticosteroids for chemo-induced N/V?
Not fully determined as antiemetic, anti-inflammatory
179
ROA of Corticosteroids for chemo-induced N/V?
PO and IV
180
Use of Corticosteroids for chemo-induced N/V?
Effective for both acute & delayed
*improves antiemetic activity of 5HT3 antagonists and Substance P/NK-1 antagonists
181
Side effects of Corticosteroids for chemo-induced N/V?
insomnia, jitters (only using short term for few days), fluid retention, blood glucose levels in DM
182
Special populations use of Corticosteroids for chemo-induced N/V?
Caution in elderly (lowest dose/shortest duration possible)
183
MOA of Olanzapine (Zyprexa) for chemo-induced N/V?
Second-gen antipsychotic w/ moderate antagonism of 5HT3, dopemine, histamine
184
Use of Olanzapine (Zyprexa) for chemo-induced N/V?
Off label for acute & delayed along w other agents (dexa, serotonin antagonsists) for mod-high emetogenic agents
185
ROA of Olanzapine (Zyprexa) for chemo-induced N/V?
PO (dissintegrating tab: ODT)
186
Side effects of Olanzapine (Zyprexa) for chemo-induced N/V?
Sedation, hyperglycemia, dizzy, wt gain
187
Dopamine antagonsists for chemo-induced N/V?
Prochlorperazine, Promethazine
188
MOA of Dopamine antagonsists for chemo-induced N/V?
Mostly dopamine antagonsim, phenothiazine class of meds
189
Use of Dopamine antagonsists for chemo-induced N/V?
w/ others or monotherapy w/ low emetogenic chemo (effective to stop vomiting once begun-breakthrough)
190
Side effects of Dopamine antagonsists for chemo-induced N/V?
Sedation, extrapyramidal effects, constipation, dry mouth
191
Benzodiazepines for chemo-induced N/V?
Lorazepam, Alprazolam
192
MOA of Benzodiazepines for chemo-induced N/V?
Anxiolytic activity
193
ROA of Benzodiazepines for chemo-induced N/V?
PO and IV
194
Uses for Benzodiazepines for chemo-induced N/V?
Prevent anticipatory CINV
*no antiemetic properties
*good if wanting to sleep through N/V
195
Precautions w/ Benzodiazepines for chemo-induced N/V?
Fall risk, additive risk w/ other sedatives
196
Special population use for Benzodiazepines for chemo-induced N/V?
Monitor doses in older adults (Beers)
197
MOA of Scopolamine patch for motion sickness?
Blocks Ach at smooth muscle, secretory glands and CNS
198
Onset of Scopolamine patch for motion sickness?
6-8 hrs
199
Uses of Scopolamine patch for motion sickness?
Behind ear at least 4 hrs before, change every 3 days (can be used for CINV)
200
Side effects of Scopolamine patch for motion sickness?
Anticholinergic effects: dry mouth, sedation, constipation, urinary retention, blurred vision
201
Special populations use of Scopolamine patch for motion sickness?
AVOID IN PREGNANCY and older adults (Beers)
202
Antihistamines for motion sickness?
Dimenhydrinate, Meclizine
203
MOA of antihistamines for motion sickness?
Block H1 R's, crosses BBB
204
Uses of antihistamines for motion sickness?
Prevention/tx of motion sickness, N/V, vertigo (short trips)
205
Onset of antihistamines for motion sickness?
15-30 min
206
Duration of Dimenhydrinate for motion sickness?
4-6 hrs
207
Duration of Meclizine for motion sickness?
24 hrs
208
Side effects of antihistamines for motion sickness?
Weak anticholinergic activity: dry mouth, sedation, constipation, urinary retention, blurred vision
209
Special population use w/ antihistamines for motion sickness?
Caution in older adults (Beers), Kids okay for use
