Exam 9: GI/CNS Flashcards

1
Q

stomach protective mechanisms

A

bicarbonate - neutralizes H+ that penetrates the mucus

prostaglandins - stimulate secretion of mucus and bicarb

COX enzymes - prostaglandin synthesis?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

antacids

A

aluminum, calcium, magnesium, sodium bicarb

decrease acidity by neutralizing w/ alkaline substances, decrease pressure on sphincters, increase good acid in stomach

magnesium: contra w/poor renal function, can cause diarrhea
aluminum - constipation
calcium - hypercalc & metabolic alkalosis
sodium - HTN & HF

take 1 hr apart from other medications because impacts absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

cimetidine

A

H2 blocker - OTC - not recommended now

liver enzyme inhibitor -> can’t take w/ a lot of meds

crosses BBB -> CNS effects, antiandrogen effects -> gynecomastia, reduced libido, impotence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

famotidine

A

H2 blocker - decrease the secretion of gastric acid

65% decrease in acid release

no liver enzyme inhibition -> less drug interaction, less ADRs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

omeprazole/pantoprazole

A

PPI - decrease the secretion of gastric acid (sometimes for critically ill)

90% decrease in acid release (most effective) -> irreversibly blocks pump at parietal cells

ADR: long term -> PNA, osteoporosis (dec absorption of calc), rebound acid hypersecretion, hypomagnesemia (dec absorb), gastric cancer

teaching for ADRs: hypomag s/s (?), 30 min to 1 hr before eating (before breakfast)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

sucralfate

A

indic: PUD, not GERD (sometimes for critically ill)

coats the ulcer and protects from acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

misoprostol

A

MOA: analog of prostaglandin (stimulates mucus and bicarb secretion)

NSAID related ulcers

off label for abortion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

H. pylori treatment

A

most PUD caused by H. pylori (70%)

multiple abx + antisecretory agent (H2 or PPI) for 10-14 days

Clarithromycin
Amoxicillin
Metronidazole
Bismuth
Tetracycline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

ondansetron

A

antiemetic - most effective (Zofran)

MOA: Serotonin 5HT3 receptor antagonist (disrupt the pathway to CTZ) and in the intestinal wall/stomach

PO, ODT, IV - uses: CINV, PONV, hyperemesis

ADR: drowsy, HA, diarrhea, QT prolong-> Torsades, serotonin syndrome

Education: rest, notify of pregnancy, notify of irregular HR

EKG - contra: Torsades, brady, blocks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

haloperidol/droperidol

A

dopamine antagonists (butyrophenones)

PONV, CINV

ADRs: EPS, Sedation –> respiratory depression, hypo, prolong QT EKG

pull from other deck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

dopamine antagonists ADRs

A

anticholinergic, sedation -> resp depress (promethazine) , EPS (haldol), tissue injury, hypo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

metoclopromide

A

dopamine antagonists & prokinetic (empties stomach) (Reglan)

PONV, CINV (DM gastroparesis, GERD) contras: GI bleed, obstruct, perf

ADR: high doses -> sedation, diarrhea, EPS (tardive)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

promethazine

A

dopamine antagonists (Phenergan) (phenothiazines)

IV, dark vial protected from light (filtered needle),

tissue injury at site (toxic), contra: less than 2 yrs

ADRs: sedation -> respiratory depression,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

lorazepam

A

MOA: enhances GABA

CINV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

methylprednisolone/dexamethasone

A

off-label use for CINV

used with arepitant or zofran

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

aprepitant

A

blocks neurokinin-type receptors in CTZ

unrelenting PONV & CINV -> delayed effectiveness

ADR: fatigue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

dymenhydrinate/diphenhydramine

A

(Dramamine)/(Benadryl)

antihistamine for motion sickness, contra: glaucoma

ADRs: sedation, anticholinergic effects

admin 30-1hr prior to motion activity (as early as possible)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

scopolamine

A

anticholinergic for motion sickness (most effective), contra: glaucoma

transdermal patch behind ear - apply 4 hours before activity

ADR: anticholinergic side effects (can’t see, can’t pee, can’t spit, can’t poop)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

dronabinol/nabilone

A

cannabinoid - activates cannabinoid receptors near CTZ

CINV, used to stimulate appetite in patients w/AIDs

ADR: abuse potential, tachy, hypo, drowsy

controlled substance, avoid other CNS depressants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

antidiarrheals

A

note if pt actually needs - often standing orders

E. coli - most common (cipro tx)

C. diff - metronidazole & vancomycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

bismuth subsalicylate

A

Pepto
antidiarrheal, antiemetic, PUD tx contra: pts w/coag disorders, kids w/viral febrile illness

educ: tarry stools, contains aspirin, OD=ringing in ear (aspirin tox)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Diphenoxylate with Atropine

A

antidiarrheal (lomotil)

diphenoxylate = opioid -> decrease intestinal motility (most effective)
atropine = added to counteract anticholinergic effects and make non addictive

sched V

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Loperamide

A

antidiarrheal (immodium) - bulk forming

analog of meperidine but no narc or pain effect, doesn’t cross BBB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Polycarbophil/methycellulose

A

constipation tx -> same as dietary fiber (bulk-forming laxatives) (citrocel/metomucil)

sometimes used for diarrhea as well

take w/ 8oz H2O –> can solidify in GI tract w/o adequate liquids

contras: pts w/hypercalcemia for FiberCon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Docusate Sodium

A

constipation tx (stool softener) –> increases intestinal fluid secretion and inhibits reabsorption so stains in stool

prevent straining for BM often in hospital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Bisacodyl/senna

A

stimulant laxative -> irritates nerve endings in the intestinal mucosa to stimulate motility and fluid movement in bowel

PR: burning sensation, 6-8 hr onset

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Magnesium hydroxide/sodium phosphate

A

(milk of mag) (fleet) osmotic laxative -> retains and draws water into lumen to soften feces

ADRs: substantial fluid loss, magnesium contra for renal, sodium contra for HF/HTN

educ: encourage to drink, renal function labs

28
Q

lactulose

A

saline osmotic laxative

uses: constipation & hepatic encephalopathy -> known to pull serum ammonia into the bowel for excretion

29
Q

Polyethylene Glycol

A

is bowel prep when combined with electrolyte solution

Golytely and Move-Prep

30
Q

bristol stool chart

A

4 is ideal, want a 4-5 and don’t want to see 1-3 or 6-7

31
Q

alosetron

A

IBS-D tx

slows down bowel, increases absorption of H2O and Na+, increases firmness of BM

ADRs: constipation, impaction, obstruction, ischemic colitis

32
Q

orlistat

A

weight loss tx

inhibits gastric and pancreatic lipases to decrease absorption of fats

ADRs: oily rectal seepage, leaky flatulence, fecal urgency, vit deficiencies

33
Q

carbedopa/levadopa

A

dopaminergic - converts to dopamine, crosses BBB

carbe allows more levo to enter brain (2% vs 10%) –> important because can give smaller dose and fewer ADRs

N/V, dyskinesia, psychosis, hypotens, dysrythmias

on-off phenomenon –> abrupt loss of effect

don’t eat high protein meals (spread throughout the day)

interacts w/ antipsychotics, MAOIs (HTN)

34
Q

pramipexole

A

dopamine agonists - directly stimulates dopamine receptors

early/mild s/s, better absorption

no dyskinesias, but still hallucinations/daytime drowsy/postural hypo

35
Q

entacapone

A

COMT inhibitors - blocks enzyme that inactivates dopamine

given w/ levodopa to be more effective (longer 1/2 life) and smaller doses

“stalevo” = levo/carbe/entacapone

ADRs: levo’s adrs

36
Q

benztropine

A

anticholinergic - lowering acetylcholine compared to dopamine

reduces tremors/rigidity, not as effective as other agents

anticholinergic ADRs

37
Q

selegiline

A

MAO-B inhibitor stops breakdown of dopamine

used alone or w/levodopa

start early in disease

large doses –> inhibit MAO-A as well (norepi & serotonin) –> also need to be careful of tyramine rich food (HTN crisis) and serotonin syndrome

38
Q

amantidine

A

Parkinsons - MOA unclear, originally antiviral

39
Q

Alzheimers

A

neurodegenerative, no cure

acetylcholine 90% below norm, neurofibrillary tangles, neuritic plaque

areas the control breathing and HR eventually destroyed –> death

40
Q

Donepezil hydrochloride

A

acetylcholinesterase inhibitors (stop the enzyme that breaks down acetylcholine)

all levels of severity

ADRs: GI, dizzy, HA, bronchoconstriction, bradycardia (cholinergic effects)

avoid anticholinergic drugs (atropine, diphen, etc)

41
Q

Rivastigmine

A

acetylcholinesterase inhibitors (stop the enzyme that breaks down acetylcholine)

for mild/moderate and don’t stop disease just help w/ s/s, stopped as disease progresses

same ADRs

42
Q

Memantine

A

NMDA receptor antagonist

receptor triggered by excessive glutamate in Alzheimers that allows toxic levels of calcium into cell

MOA: slow/controls the influx of calcium into cells

only drug approved for severe s/s

ADRs: well tolerated, some dizzy, HA, confusion, constipation, hallucination

43
Q

seizure causes

A

fever, epilepsy, genetic disorders, infx, hypoxia at birth, TBI, stroke, cancer

abnormal firing of cerebral neurons

decrease in GABA and increase in glutamate

44
Q

febrile seizure tx

A

??

45
Q

AEDs

A

start low & slow, only control seizures 60-70% of the time, CNS depress and should not be stopped abruptly, SI risk

suppress discharge of over-firing neurons and suppress propagation of seizure

important to monitor serum levels for most AEDs -> adjust dosage, monitor adherence, determine the cause when seizures happen, identifying cause of toxicity (polypharm)

meds must be taken at the same time - to maintain small therapeutic range

many are liver enzyme inducers –> decrease effect of other drugs

top class causes Steven-Johnsons (flu-like, then rash)

alt tx when don’t work: vagus nerve stim, keto diet, neurosurg

46
Q

Phenytoin

A

selective inhibition of sodium channels (influx)

very narrow range - 10-20 mcg/mL

ADR: gingival hyperplasia, rash, tissue damage at site, hypoten, dysrhy, teratogenic

toxicity - nystagmus, SJ synd, unclear thinking, diplopia, sedation, ataxia, cardiac depression

educ - soft toothbrush and dental appt

only dilute w/NS

47
Q

Carbamazepine

A

suppression of sodium influx and potentiates GABA, less cognitive function effects than pheny

ADRs: rash, CNS (nystagmus, ataxia, sedation), bone marrow suppression (CBC), fetal harm, hypovolemia/natremia

oral contraceptives - need alternative decreases efficacy
warfarin - decreases effect, higher risk of clot
grapefruit - toxicity

48
Q

Valproic acid

A

suppression of calcium influx, increases availability of GABA

broad spectrum of effectiveness (v for variety) –> all types of seizures

ADRs: GI, highly teratogenic, hepatotoxic and pancreatitis, hyperamonemia

49
Q

Fosphenytoin

A

converts to phenytoin when metabolized

IV/IM - short term use for status eplilepticus

same ADRs as phenytoin

cardiac monitoring

50
Q

Ethosuximide

A

suppression of calcium influx

indic: absence seizures

don’t stop abrupt, monitor closely

51
Q

Phenobarbital

A

MOA: potentiates and mimics GABA

generalized and partial seizures, rarely used due to significant ADRs

fetal harm

52
Q

Levetiracetam (Keppra)

A

MOA unknown, binds w/ GABA

widely used in acute care PO/IV, not for absence, off label for migraine, bipolar

least amount of ADRs and risk of abuse or dependence, mild drowsy/weak/CNS, safe in pregnancy

53
Q

Lamotrigine (Lamictal)

A

blocks sodium and partially calcium, good for all types, also used bipolar

ADRs: CNS, teratogenic, derm, risk for SI -> increased behavior monitoring

54
Q

Pregabalin (Lyrica)

A

analog of GABA –> inhibits calcium influx

ADRs: dizzy, sedation, blurred vision, hypersensitivity, abuse/dependence

dc slowly, avoid other CNS depressants

55
Q

Topiramate (Topamax)

A

risk for SI

56
Q

Gabapentin (Neurotin)

A

approved by FDA for partial seizures, analog of GABA, mostly for off-label like nerve pain

ADRs: well tolerated but, somnolence, nystagmus

no drug interactions

57
Q

Oxycarbazepine(Trileptal)

A

most common of newer AEDs

gen and part seizures, blocks sodium channels, more expensive than older AEDs but better tolerated

ADRs: CNS, hypoNa, hypothyr, bone marrow suppression, rash/SJ, hypersens

58
Q

status epilepticus treatment

A

LOC, tachy, HTN, fever, hypoglycemic, acidotic, hypoxic

immediate: airway, rescue med, hypoglycemia

IV –> glucose, AED, benzo (lorazepam)

59
Q

migraines

A

etiology not known (no identifiable cause), but vessel dilation causes pain

CGRP increased (vasodilate & inflame), S5HT decreased (protective)

estrogen help only hormone related

60
Q

sumatriptan

A

1st line for abortive, constricts intracranial vessels, PO/SQ/IN/transdermal (PO fastest onset <30 min, SQ=30 min, IN = <60 min)

MOH - medication overuse HA, turns episodic HA into chronic from too many abortive meds

ADRs: heavy arms/chest pressure, coronary vasospasm, teratogenic; contra: CAD/HTN

sero syn w/ SSRIs

61
Q

opioids

A

INH agent

migraine lasts longer, so have to take more and more, MOH (acute -> chronic HAs)

62
Q

ergotamine

A

2nd line abortive, PO/IN/sublingual/PR; contras: CAD/HTN/PVD

N/V (admin w/antiemetic), risk of dependence, rebound headaches, vasoconstrict and HTN w/triptans

OD = sever tissue ischemia in the periphery from constriction (gangrene)

63
Q

ubrogepant

A

CGRP antagonist, very expensive

64
Q

preventative migraine treatment

A

bblkrs (propanolol), TCAs, AEDs - get put on if more than 2 migraines a month

Serotonin receptor agonist

65
Q

botox

A

preventative, can reduce # and severity of migraines