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1
Q

bactericidal drugs

A
penicillins
cephalosporins
aminoglycosides
vancomycin
aztreonam
imipenem
fluroroquinolones
metronidazole
polymyxins
quinupristin-dalfopristin
bacitracin
2
Q

bacteriostatic drugs

A
erythromycin (macrolides)
clindamycin
tetracycline
chloramphenicol
sulfonamides
trimethoprim
nitrofurantoin
3
Q

narrow spectrum

A

only G+ or G-: isoniazid against mycobacterium

4
Q

extended spectrum

A

G+, some G- i.e. ampicillin

5
Q

broad spec

A

wide variety of G+ and G-: tetracycline, chloramphenicol, imipenem

6
Q

expense of drug administration

A

IV>IM>oral (cheapest)

7
Q

drugs that inhibit synthesis of bacterial cell walls: PCN (B-lactam): natural penicillins

A

G, V Potassium, G Procaine, G Benzathine, G Benzathine + Penicillin G Procaine

8
Q

drugs that inhibit synthesis of bacterial cell walls: PCN (B-lactam): Penicillinase resistant Penicillins (anti-staph)

A

methicillin
nafcillin
oxacillin

9
Q

drugs that inhibit synthesis of bacterial cell walls: PCN (B-lactam): ext. spec PNC

A

ampicillin

amoxicillin

10
Q

drugs that inhibit synthesis of bacterial cell walls: PCN (B-lactam): antipseudomonal

A

Ticarcillin + clavulanate potassium (Timentin)

Piperacillin + Tazobactam (Zosyn)

11
Q

drugs that inhibit synthesis of bacterial cell walls: PCN (B-lactam): monobactams

A

aztreonam

12
Q

drugs that inhibit synthesis of bacterial cell walls: PCN (B-lactam): carbapenems

A

Imipenem + Cilastatin

13
Q

drugs that inhibit synthesis of bacterial cell walls: PCN (B-lactam): B-lactamase inhibitors

A

Clavulanic acid, Tazobactam

14
Q

drugs that inhibit synthesis of bacterial cell walls: cephalosporin (B-lactam): 1st gen

A

Cefazolin

Cephalexin

15
Q

drugs that inhibit synthesis of bacterial cell walls: cephalosporin (B-lactam): 2nd gen

A

Cefaclor
Cefoxitin
Cefuroxime
Cefprozil

16
Q

drugs that inhibit synthesis of bacterial cell walls: cephalosporin (B-lactam): 3rd gen

A

Ceftriaxone
Cefixime
Cefotaxime
Ceftazidime

17
Q

drugs that inhibit synthesis of bacterial cell walls: cephalosporin (B-lactam): 4th gen

A

Cefepime

18
Q

drugs that inhibit synthesis of bacterial cell walls: cephalosporin (B-lactam): 5th gen

A

Ceftaroline

19
Q

other drugs that inhibit bacterial cell wall synthesis

A

vancomycin

bacitracin

20
Q

drugs that alter cell membrane permeability

A

Polymyxin B

Daptomycin

21
Q

drugs that inhibit bacterial protein synthesis: Tetracyclines

A

short-acting: Tetracycline
long-acting: Doxycycline, Minocycline
new: Tigecycline

22
Q

drugs that inhibit bacterial protein synthesis: Macrolides

A
Erythromycin base
" Estolate, " Stearate, " Ethylsuccinate, " Lactobionate
Clarithromycin
Azithromycin
Telithromycin
23
Q

drugs that inhibit bacterial protein synthesis: Aminoglycosides

A
Gentamicin; generic: Garamycin, Jenamicin
Tobramycin; generic: Nebcin
Amikacin; generic: Amikin
Streptomycin
Neomycin
24
Q

drugs that inhibit bacterial protein synthesis: Misc.

A

Clindamycin
Quinupristin/Dalfopristin
Linezolid

25
Q

act on 50S ribosomal subunit

A

Cloramphenicol, macrolides, clindamycin, quinupristin/dalfopristin, linezolid

26
Q

act on 30S ribosomal subunit

A

Aminoglycosides, Tetracyclines

27
Q

drugs that act as anti-metabolites: Sulfonamindes

A
Silver Sulfadiazine (SILVADINE): topical
Trimethoprim-sulfamethoxazole
28
Q

drugs that inhibit nucleic acid synthesis: Fluoroquinolones

A

Ciprofloxacin (CIPRO)
Levofloxacin (LEVAQUIN)
Moxifloxacin (AVELOX)

29
Q

Misc. drugs that act via nucleic acids

A

Metronidazole
Nitrofurantoin
Rifampin

30
Q

empirical therapy

A

“best guess” therapy, br. spec/combo abx
guided by Gs, site of inf, clinical experience, local hospital antibiogram susc. reports
-should be changed to rational therapy (narrow spec) when susc. tests performed and org. ID’d

31
Q

epsilometer (E) test:

A

also determines MIC, plastic strip containing gradient of known conc. abc placed on agar plate containing pt’s bac. isolate

32
Q

how to monitor antimicrobial activity in vivo

A

serum inhibitory titer: greatest dilution of pt’s serum that inhibits visible growth of pt’s infecting pathogen
bactericidal titer: plate out above no-growth samples onto abx-free plates

33
Q

min. drug conc. at infected site should be..

A

> = MIC, ideally 2-4x MIC

abscesses must be drained

34
Q

BBB may prevent..

A

penetration of drug into CSF

-but during infection BBB is diminished (opened up tight junctions of cerebral capillaries)–>inc. penetration

35
Q

this may prevent abx penetration to site of action (and dec. levels of free drug)

A

abx binding to plasma proteins

36
Q

med doses may need to be adjusted for..

A

renal/hepatic failure
newborns
oral vs. parenteral admin

37
Q

bactericidal or bacteriostatic?

A

cidal is better, esp. if immunecomp

38
Q

strains of these are resistant to all known drugs

A

Enterococci
Pseudomonas
Enterobacter

39
Q

bacterial resistance factors

A

indiscrim. use (misuse)
delay in optimal tx
admin of subopt. dose
tx during dormant stage
inability to reach inf. site (CNS, eye, prostate, abscess)
defective funct. status of host defense mech
agricult. used of abx in livestock

40
Q

how microorganisms produce resistance

A

mutation and selection

i. e. resistance to:
- strep (ribosomal mut.)
- quinolone (DNA gyrase)
- linezolid (rRNA)
- rifampin (RNA polymerase)
- M. tuberculosis

41
Q

resistance mediated by genetic exchange

A

HGT:
transformation (PCN res. in pneumo.)
transduction (Staph, penicillinase)
conjugation

42
Q

conjugation

A

2 sets of genes transferred: R-determinant (resistance) and resistance transfer factor (RTF)–>ind or combine to for R-factor

  • can have >1 abx resis. gene!
  • *>50% ppl have int. bac containing R-factors
43
Q

transposon

A

DNA sequences that can “jump from place to place”, can carry drug resis. genes
plasmid–>plasmid
plasmid–>chromosome (and vis versa)

44
Q

biochem mechs of drug resistance

A
  1. dec. perm. of org to drug: porins do not allow in anymore (G-) OR active efflux (tetras)
  2. inactivation of abx by enzymes: (PCN, Chloramphenicol, Aminoglycosides): B-lactamases (+ and -) acetyl/phosphoryl/adenylate drug (amino glycosides, G-)
  3. altered drug target site: PBP w/ altered affinity for drug, mut. in FQ target (DNA gyrase)
45
Q

forms of synergism seen with combo abx tx

A
  • block of seq. steps in metabolic pathway (Trimethoprim + Sulfamethosazole–>folic acid)
  • inhib. enz. inact. of abx (B-lactamase inhibitor)
  • enhanced abx uptake by bac (aminoglycoside + B-lactam)
46
Q

synergism

A

4x or greater reduction in MIC or MBC when drug combined

47
Q

antagonism

A

> 50% MIC of each drug needed to produce inhibition of growth

48
Q

antagonism exs.

A

bacteriostatic antags. bactericidal (need actively growing org) (PCN + chlortetracycline)
induction of enz. inact.: imipenem (induces B-lactamase) + piperacillin (susc. to B-lactamase)

49
Q

combo abx tx uses

A

mixed bac inf
unknown specific cause-empirical tx (i.e. pneumonia: macrolides for M. pneumo + ceftriaxone for G-)
synergism may be nec. to kill org. (PCN + AMGS better tx for enterococcal endocarditis)
may prevent resistances (bismuth salts + amos/tetra/or clarithro + metronidazole for H. pylori)

50
Q

disadv. of combo abx tx

A

inc. toxic side effects
selection of orgs resis. to >1 abx
possible antag. effect if wrong combo

51
Q

abx ppx

A
  • post-exposure to certain microorgs: gon, syph, anthrax
  • prevent recurrent dis. in susc. pt: artific. heart valve undergoing dental proc. to prevent bac endocarditis, emphysema pts to prevent chron. bronchitis, frequent UTIs
  • surgical procedures: 0-2 hrs before, during, 3-4 hrs after
  • trauma contam wounds
52
Q

abx ppx approved surgical procedures

A

contam, clean-contam operations, dirty wounds, prosthetic placement, immune comp host (any proc)

53
Q

superinfections

A

new infection appears during chemotx for other infection

54
Q

why do superinfections occur?

A

doses of abx can inhibit NF growth–>other orgs uninhibited

55
Q

superinfection orgs

A

enterobacteriaceae, pseudomonas, candida, fungi

56
Q

inc. risk of superinfection w/

A

brd spec abx, longer course, oral admin over IM/IV

57
Q

abx misuse

A
  • for viral infection (fever 2 wks which could be tb, intra-abd. abscess, inf. endocarditis, Ca
  • undetermined cause (NOT antipyretics)
  • improp. dosage
  • abx has to reach inf. site (get rid of pus and kidney stones)
  • lack of adeq. bac info: more testing!
  • improp. duration of tx (finish your abxs!)
58
Q

receptors at parasympathetic end organs (and symp. sweat glands)

A

muscarinic: M1-5, 2,3*most common

59
Q

B1 adrenergic receptor

A

heart (inc. force, rate)
kidney (mediate renin secr)
brain

60
Q

B2 adrenergic receptor

A

airway, BVs of skel music, pregnant uterus

-smooth musc relaxation

61
Q

B3 adrenergic receptor

A

bladder smooth musc: relaxation

62
Q

a1 adrenergic receptor

A

most BVs, urinary sphincters, eye

-mediate contraction of smooth musc

63
Q

a2 adrenergic receptor

A

some end organs, @ adrenergic nerve endings and in CNS

64
Q

organs that received both parasym and symp innervation

A

heart, GI, bladder, eye, etc

65
Q

organs w/ only symp innervation

A

adrenal medulla, spleen capsule, pilomotor musc, BVs of skin and skeletal muscd

66
Q

reserpine blocks adrenergic system..

A

produces exaggerated cholinergic response: inc. GI motility, secretions

67
Q

atropine blocks cardiac vagal influence..

A

cardiac acceleration, reduction of GI motility, secretion

68
Q

eye sympathetics

A

a1: mydriasis (dilator musc. of iris)
B2: inc. aqueous humor

69
Q

gland sympathetics

A

a, B

B2: respiratory secretions

70
Q

heart sympathetics

A

B1, B2:

inc. rate (SA node), contractility (ventricles), automaticity, conduction velocity (SA, AV nodes)

71
Q

BVs sympathetics (mucosa, saliva, skin, splanchnic)

A

a1, a2: constriction

72
Q

BVs sympathetics (skeletal musc)

A

a1: constriction
B2: dilation

73
Q

BVs parasyms

A

no PS inn to most vasc beds, but muscarinic rec are present on endo cells: activation of these receptors: NO-med. vasodilation

74
Q

airway symps

A

relaxation: B2

75
Q

GI symps

A

relaxation: a1, a2, B1, B2

dec. motility

76
Q

Urinary bladder wall, sphincter, prostate sympathetics

A

relaxation: B2, B3 (widens out)
contraction: a1 (sphinter)

77
Q

kidney JG cell symp

A

inc. renin secretion: B1

78
Q

uterus symp

A

contraction: a1
relaxation: B2 (later on)

79
Q

male sex organs symp

A

ejaculation: a1

80
Q

male sex organs PS

A

erection

81
Q

liver, fat cells symp

A

inc. glucose output: B2

inc. FA output: B1

82
Q

skin pilomotor music and sweat glands symps

A

contraction: a1
secretion: muscarinic

83
Q

eye PS

A

miosis (pupillary sphincter musc)

accommodation- near vision (ciliary musc.)

84
Q

PS ciliary musc contraction also…

A

inc. pressure on trabecular meshwork–>inc. outflow of AH in canal of Schlemm and dec. intraocular pressure

85
Q

PS action on lacrimal gland

A

inc. tear production

86
Q

acetylcholine is formed by action of

A

choline acetyl transferse (choline + acetate)

87
Q

ACh pathway

A

stored in vesicles–>AP–>inc. IC [CA2+]–>storage vesicle fuses with plasma mem–>ACh rel. into synapse–>acts on postmen. rec–>activates transduction pathway–>response

88
Q

nicotinic rec. usually coupled to

A

Na+ channels

89
Q

muscarinic rec may be coupled to

A

phospholipase C, K+ channels

or act thru G-protein mechanism to inhibit adenylate cyclase

90
Q

actions of ACh terminated by

A

acetycholinesterase (rapid hydrolysis) choline and acetate recycle to ACh by presyn. nerve ending

91
Q

specific sites where drugs can modify cholinergic system

A
  • ACh synthesis
  • ACh release
  • stim or blockade of postmen. receptors
  • inhib. of AChesterase
92
Q

tyrosine–>DOPA–>DA–>NE

A
  1. tyrosine hydroxylase* 2. DOPA decarboxylase 3. Dopamine B-hydroxylase
93
Q

NE acts on postsyn. rec

A

a1 or B1–>signal transduction pathway

–>response

94
Q

Noradrenergic signal transduction pathway

A

typ. involve G-prot. coupled rec.
B-rec: coupled to adenylate cyclase
a-rec: coupled to pholspholipases or ion channels

95
Q

NE can also act on

A

a2 rec on presynaptic nerve ending: feedback inhibition on NE release

96
Q

action of NE terminated mostly by

A

rapid reuptake into presyn. nerve ending, med. by high affinity transport pump–>broken down by MAO or requestered in storage vesicles

97
Q

sites of pharm intervention on Noradrenergic system

A
  • synth, storage, del of NE
  • stim or block of postsyn a1, B1, B2
  • stim or block of presyn a2 rec
  • inhib of NE reuptake
  • inhib of NE metab by MAO
98
Q

direct acting muscarinic agonists

A
acetycholine (Miochol-E)
carbachol (Isopto Carbachol)
methacholine (Provocholine)
bethanechol (Urecholine)
pilocarpine (Salagen/Ocusert Pilo)
cevimeline (Evoxac)
99
Q

indirect acting drugs: cholinesterase inhibitors -reversible

A
edrophonium (Tensilon)
physostigmine/eserine
neostigmine (Prostigmin)
pyridostigmine (Mestinon)
rivastigmine (Exelon)
donepezil (Aricept)
carbamate insecticides (Carbaryl)
100
Q

indirect acting drugs: cholinesterase inhibitors-irreversible

A

DFP/diisopropylfurophosphate/isoflurophate and echothiophate
organophasphate insecticides (Parathion, Malathion)
nerve gases in chem warfare (Sarin, soman, Tabun, Vx)

101
Q

indirect acting drugs: cGMP phosphodiesterase (PDE-5) inhibitors

A

sildenafil (Viagra)
vardenafil (Levitra)
tadalafil (Cialis)

102
Q

Cholinesterase Reactivator

A

pralidoxime/2-PAM (Protopam)

103
Q

Toxins

A

botulinum toxin (BOTOX)

104
Q

Muscarinic ANTAGONISTS (anticholinergics)

A
atropine (hyoscyamine) and homatropine
scopolamine and methscopolamine
dicyclomine (Bentyl)
propantheline
glycopyrrolate (Robinul)
ipratropium (Atrovent)
tiatropium (Spiriva)
benztropine (Cogentin)
trihexyphenidyl (Artane)
tolterodine (Detrol)
oxybutynin (Ditropan)
solifenacin (VESIcare)
tropicamide (Mydriacyl)
105
Q

Botulinum toxin (BOTOX) acts by

A

inhib. syn/rel of ACh

106
Q

M1 rec

A

in symp. gang and myenteric plexus, unclear function

possibly stomach: med gastric acid sec

107
Q

M2 rec

A

located in heart, some smooth musc

108
Q

M3 rec

A

glands, smooth musc, BVs

109
Q

ACh stimulated muscarinic rec in what kind of manner

A

dose/conc. dependent, relatively nonselective

110
Q

Nm vs Nn rec.

A

Nm rec. located on sk. music at NM junc, Nn rec. located in autonom ganglia and adrenal medulla

111
Q

at low/mod doses ACh…

at high doses…

A

-stim both types nicotinic receptor
-desensitizes rec at high conc.–>gang. blockade, muscle paralysis
(in contrast to muscarinic: no desensitization, just plateau)

112
Q

PS heart

A

atria, SA node, AV node, minor to ventricles

  • dec. HR by slowing firing of SA nodal pacemaker cells and slowing AV conduction
  • only min. effects on ventricular contractility and automaticity
113
Q

PS BVs

A

not inn. by PS, but endothelial cells in most BVs do contain muscarinic rec., stim. by ACh or muscarinic agonists–>NO (cGMP) med vasodilation–>dec. in BP
-enhanced by cholinesterase inhibs like edrophonium, blocked by muscarinic antagonists such as atropine

114
Q

BVs that receive more PS inn.

A

corpus cavernosum, some cerebral, coronary, skeletal musc. BVs

115
Q

PS eye

A

pupillary constrictor muscles: miosis
ciliary muscle: accommodation
-lowered IOP (outflow of AH)

116
Q

PS smooth muscle

A

bladder, stomach, sm. intestine, bowel, etc.

-typ. stim. contraction of sm. musc to increase motility

117
Q

PS glands

A

salivary, lacrimal, mucosa of GI, airway, etc.

-stimulate secretions (muscarinic ANTAGONISTS have drying effect)

118
Q

PS airways

A

bronchoconstriction and inc. respiratory secretions

-

119
Q

Muscarinic ANTAGONISTS useful in asthma tx

A

ipratropium (Atrovent) tiatropium (Spiriva)

muscarinic agonist or cholinesterase inhibs. can aggravate asthma

120
Q

PS GI

A

stimulate GI motility and secretion

also reg by “enteric NS”

121
Q

PS NM junction

A

ACh released by motor neurons can act on nicotinic rec. at motor end plate to cause musc. contraction

  • receptors are DESENSITIZED if excess ACh (i.e. high dose cholinesterase inhib.)–>musc. paralysis
  • exogenously admin. ACh has little effect on skel. musc.
  • nicotinic effects can be inhib by ganglionic and NM blockers
122
Q

direct acting muscarinic agonist activity

A

inc. GI motility, secretion
dec. HR
dec. BP due to dec. CO and direct vasodilation
contraction of bladder, relax. of ur. sphincters
miosis and dec. IOP
stim of secretions

123
Q

adverse effects of muscarinic stimulation

A

hypotension, bradycardia, chronchoconstriction, diarrhea, cramping, urinary incontinence, excessive sweating, salivation

124
Q

major tx uses of muscarinic agonists

A

promote GI motility (bethanechol)
tx urinary retention (bethanechol)
tx of glaucoma (pilocarpine, acetylcholine, carbachol)
tx of sal. gland dysfunc (pilocarpine, cevimeline)
pulmonary function testing in asthma (methacholine)- dangerous dx test

125
Q

when muscarinic agonists are contraindicated/used w/ caution

A

asthma, bradycardia, hypotension, vasomotor instability, CAD, peptic ulcer disease, hyperthyroidism, weakened smooth musc of bladder/GI, urinary/intestinal obstruction

126
Q

DO NOT give choinesters..

A

IV or IM, but rather subQ, orally, topically(eye)

127
Q

acetylcholine

A

limited, tx for glaucoma

–>rapidly hydrolyzed by pseudocholinesterase in plasma

128
Q

carbachol

A

analog of ACh, resistant to hydrolysis

  • stim both muscarinic and nicotinic
  • topically for glaucoma
129
Q

methacholine

A

ACh analog, stim muscarinic (little nicotinic effect)

used in asthma pulmonary function testing

130
Q

bethanechol (Urecholine)

A

ACh analog, resis to hydrolysis, direct muscarinic agonist (little nicotinic effect)
stim. GI motility and tx for urinary retention

131
Q

pilocarpine (Salagen, Ocusert Pilo)

A

muscarinic agonist, tx for glaucoma and xerostomia (dry mouth) due to poor salivary secretion

132
Q

cevimeline (Evoxac)

A

muscarinic agonist, tx for salivary gland dysfunction

133
Q

muscarine

A

natural in mushrooms (Inocybe and Clitocybe)

  • salivation, lacrimation, nausea, extreme GI hypermotility, bronchospasm, bradycardia, hypotension, shock
  • can be tx with high dose atropine (1-2 mg IM every 30 min)
134
Q

cholinesterase inhibitors have similar effects as muscarinic agonists, plus

A

stimulation of skeletal muscle–>paralysis of skeletal muscles @ toxic doses

135
Q

toxic effects of cholinesterase inhibitors (cholinergic crisis)

A

i. e. organophosphate insecticide/nerve gase poisoning
- SLUDGE (salivation, lacrimation, urination, defection, GI distress, emesis)
- skel musc fasciculations–>paralysis
- bradycardia, hypotension, shock
- severe miosis
- CNS stimulation and seizures–>coma
- chronic exposure to some–>demyelination of axons and various neuropathies

136
Q

tx of acute cholinesterase inhibitor poisoning

A
  • administer high doses atropine (2-4 mg IV initially) followed by 2 mg IM every 10 min until symptoms disappear to block muscarinic receptors
  • admin pralidoxime to reactivate enzyme (effective w/ organophosphates only)
  • provide additional symptomatic tx as needed (i.e. diazepam for seizures)
137
Q

major tx uses of cholinesterase inhibitors: myasthenia gravis

A

dx: endrophonium test
tx: pyridostigmine, neostigmine
MG is AI against nicotinic rec. at motor end plate

138
Q

Tensilon Test

A

admin 2-8 mmg edrophonium; improvement in musc. strength suppors myasthenia gravis dx
if musc. wkns worsens: indicative of musc. wkns from exc. doses other cholinesterase inhibitors (cholinergic crisis)
- 5 min duration of action

139
Q

other (more commonly used) myasthenia gravis dx tests

A

electromyography (EMG)

serology

140
Q

cholinesterase inhibitors: tx of glaucoma

A
cholinergic agonists (acetylcholine, carbachol, pilocarpine)
cholinesterase inhibitors (echothiophate)
again..these contract ciliary musc-->put tension on trabecular meshwork-->inc. outflow of AH through canal of Schlemm
141
Q

cholinesterase inhibitors: tx of Alzheimer’s

A

loss of cholinergic neurons (Nucleus basal is of Meynert)–>raise ACh levels and reverse deficit
tetrahydroaminoacridine (Tacrine)* original, but causes liver damage
rivastigmine (Exelon)
donepezil (Aricept)
galantamine (Reminyl)

142
Q

other uses of cholinesterase inhibitors

A
  • tx of poisoning by atropine/other antimuscarinic drugs: physostigmine
  • reversal of NM blockade by nondepol. NM blockers: neostigmine, pyridostigmine
  • tx of atony of bladder or GI tract (i.e.: urine retention, paralytic ileus, etc)
  • pyridostigmine used by military to protect against nerve gas: ““pre-exposure antidotal enhancement”
143
Q

CI’s and precautions in cholinesterase inhibitor use

A

asthma
bradycardia, hypotension, CAD
peptic ulcer disease
urinary or intestinal obstruction

144
Q

reversible cholinesterase inhibitors, quaternary ammonium compounds- cannot enter CNS

A

edrophonium (Tensilon), neostigmine (Prostigmin) pyridostigmine (Mestinon)

145
Q

reversible cholinesterase inhibitor, nonquaternary-so able to enter CNS

A

physostigmine/eserine (Antilirium)
tx for atropine/other antimuscarinic agent poisoning
(fallen into disfavor, esp. with tricyclic antidep. OD)

146
Q

Organophosphate insecticides

A

parathion, malathion
–>need to be oxidized to active metabolites (paroxone and malaoxone) happens faster in insects, cannot detoxify
(but can still cause toxicity in humans)
-can be absorbed thru skin
-S&S typical of cholinesterase inhibs.
-tx poisoning w. atropine, pralidoxime (& other sympt. support)

147
Q

Carbamate insecticides

A

carbaryl

  • absorbed less thru skin
  • tx poisoning w/ atropine, pralidoxime is NOT useful in tx of carbamate insecticides!
148
Q

DFP/Isoflurophate and Nerve Gases

A

Sarin
potent, toxic, irreversible cholinesterase inhibitors
-S&S typ. for cholinesterase inhibs.
-tx poisoning w/ atropine and pralidoxime
-DFP/Isoflurophate: glaucoma tx

149
Q

Pralidoxime/2-PAM (Protopam)

A

cholinesterase reactivator! binds phosphate grp that inhib. enzyme thereby regenerating enzyme

  • antidote for orgphos poisoning w/in 2 hours of exposure
  • does not work with carbamate insecticides
150
Q

ED drugs

A

Sildenafil (Viagra)
Vardenafil (Levitra)
Tadalafil (Cialis)
-NO activates guanylcyclase in vasc. sm musc to produce cGMP–>vasodilation–>erection
-drug inhibits cGMP phosphodiesterase type 5 (PDE-5) which breaks down cGMP

151
Q

ED drug side effects/toxicities

A
  • general vasodilation–>hypotension–>reflex inc. in HR (problem for men w/ CV disease)
  • visual distrubances: blue/green discrim. probs
  • auditory disturbances
152
Q

ED pharmacokinetics

A

oral admin, sildenafil and vardenafil onset: 30 min, pk plasma levels about 1 hr, duration 4 hrs
tadalafil longer 1/2 life, onset 45 min, and duration about 36 hrs
-metabolized by CYP3A4: potential for drug interactions
-dosage adj. for renal/hepatic disease pts

153
Q

ED drug interactions

A

erythromycin, ketaconazole, cimetidine, others metabolized by CYP3A4
vasodilators (nitrates, Ca2+ channel blockers, a1 blockers)
sympathomimetics

154
Q

botulinium toxin

A

produced by Clostridium botulinium

  • rel. of ACh from nerve endings–>affects both autonomic nerve endings (antichol. effects) and NM junction (paralysis)
  • death from diaphragmatic paralysis, 0.5-1.0 ug dose may be fatal
    tx: sympt. support (resp) + abx to toxin
  • med uses: optham. disorders, wrinkles (BOTOX), dystonia, exc. sweating, over-active bladder
155
Q

anticholinergic pharm effects

A

competitive antagonists at muscarinic receptors

  • drying of secretions
  • dec. tone and motil. of GI tract
  • relax. of bladder and urine retention
  • bronchodilation
  • mydriasis w/ cycloplegia (loss of accomm.) and inc. in IOP
  • inc. HR (*atropine may cause initial slight bradycardia)
  • CNS: sedation and amnesia at low doses; excitation and seizures at toxic doses
  • quaternary salts do NOT produce CNS effects
156
Q

therapeutic uses of anticholinergics part 1

A
  • GI disorders
  • urine incontinence
  • opth: mydriatic agents (*do NOT use in pts w/ glaucoma!)
  • anesthesiology to reduce vagal tone on heart and dry secretions; also to prevent muscarinic side effects when cholinesterase inhibs used to reverse effects of NM blockers
  • antidote for poisoning with cholinesterase inhibs. or muscarinic agonists (some mushroom poisoning)
157
Q

therapeutic uses of anticholinergics part 2

A
  • prevent motion sickness (Scopolamine)
  • Parkinson’s (benztropine, trihexyphenidyle, diphenhydramine)
  • dental proc. to inhib salivation (atropine, glycopyrrolate)
  • cardiac stim in emergencies (atropine)
  • asthma and COPD (ipratropium, tiatropium)
  • pulmonary med to dry resp secretions
158
Q

anticholinergic side effects/toxicities

A

dry mouth
dry, hot skin
constipation, urine ret.
visual disturbances, blurred vision, photophobia
CNS effects: sedation, confusion, amnesia (elderly)

159
Q

anticholinergics/muscarinic antagonist

CIs/precautions

A

glaucoma (esp. narrow angle)
prostatic hypertrophy
CV instability
severe ulcerative colitis

160
Q

acute antichol. poisoning

A

dry, hot skin/ hyperthermia
severe mydriasis, blurring, photophobia
CNS stim: agitation, halluc, seizure–>coma–>death
cessation of GI motility (no bowel sounds)
weak rapid pusle, tachy, arrhyths.

161
Q

tx of acute antichol. poisoning

A

admin of physostigmine or other cholinesterase inhibitors
benzos for seizure tx
ice baths to cool down, keep pt in dark, quiet area

162
Q

other drugs with anticholinergic side effects

A

antihistamines, antipsychotics, antidepressants, etc.

163
Q

atropine (Hyoscyamine) and Homatropine

A

-belladonna alkaloid found in nightshade (Atropa belladonna) and jimsonweed, mixture of d, l* -hyoscyamine
(semi-syn. analog), methylbromide salt does NOT penetrate CNS
prototype antimuscarinic

164
Q

atropine effects: heart

A

tachycardia w/ slight inc. CO (may have transient bradycardia)
tx for MI w/ inc. vagal tone: low CO and dec. BP

165
Q

atropine effects: BVs

A

can reverse hypotensive actions of acetylcholine/other muscarinic agonists
cutaneous vasodil and flushing of skin

166
Q

atropine effects: eye

A
  • mydriasis
  • cycloplegia (paralysis of accomm.)
  • inc. IOP
167
Q

atropine effects: GI tract

A

inhib. motility and tone (antispasmodic action for IBS)
need high dose to dec. acid sec, so H2-histamine blockers (cimetidine, ranitidine, nizatidine, famotidine, or PPIs) used for peptic ulcers instead

168
Q

atropine effects: urinary tract

A

relaxes bladder body and contracts sphincter–>retention

tx incontinence, CI in prostatic hypertrophy

169
Q

atropine effects: sweat glands

A

blocks muscarinic rec.–>inhib sweating–>rise in body temp

*children extra sensitive

170
Q

atropine effects: salivary glands

A

inhib. saliva sec. “dry mouth”

171
Q

atropine effects: respiratory tract

A

dries secretions, bronchodilation

172
Q

atropine effects: CNS

A

depressant (low doses) and stimulation (hight doses): agitation and seizures
mod-high: hallucinogenic

173
Q

atropine tx uses

A
  • preop to red sec (old) and block vagal ref on heart (new)
  • cardiac stim post-MI
  • antidote for poisoning with cholinesterase inhib/musc. agonists
  • to dry resp. sec
  • mydriatic and cycloplegic
  • antispasmodic for GI: IBS, biliary colic
174
Q

at 0.5 mg atropine

A

some cardiac slowing, mouth dryness, sweating inhib

175
Q

1.0 mg atropine

A

def dry mouth, thirst, heart accel. (slowing 1st), mild pupil dilation

176
Q

2.0 mg atropine

A

rapid HR, marked dry mouth, dil. pupils, blurred near vision

177
Q

5.0 mg atropine

A

all above + diff speaking/swallowing, restless, fatigue, HA, dry, hot skin, diff mictur., red intestinal peristalsis

178
Q

10.0+ mg atropine

A

all above + more marked, pulse rapid/wk, iris almost obliterated, vision v. blurred, skin flushed, hot dry, scarlet, ataxia, restless, excitement, hallucinations, delirium, coma

179
Q

Scopolamine (hyoscine) and Methscopolamine

A

-plant Hyoscyamus niger (henbane), chem sim to atropine
quarternary analog, does NOT cross BBB
-sim to atropine but more of CNS depressant (sed/amn) than atropine
-oral and patch form (Transderm Scop) for pref of motion-sickness, vertigo

180
Q

Dicyclomine (Bentyl)

A

nonquart. antimuscarinic

- used as intestinal antispasmodic for IBS tx

181
Q

Propantheline (Pro-Banthine)

A

antimuscarinic
-antispasmodid, IBS tx
quaternary comp. w/ few CNS effects

182
Q

Glycopyrrolate (Robinul)

A

quart. antimuscarinic (no CNS effects)
- used in anesthesiology as prep med to dry resp. sec and inhib vagal reflexes
- also used as gen purpose antimuscarinic

183
Q

Ipratropium (Atrovent)
Tiatropium (Spiriva)
aclidinium (Tudorza)

A

antimuscarinics
quat. salts admin. by inhalation for asthma and COPD tx
few systemic effects
tiatropium longer duration than ipratropium
aclidium: new drug approved for COPD (long acting in lungs, broken down by esterases in plasma: few systemic effects)

184
Q

Benztropine (Cogentin)

Trihexyphenidyl (Artane)

A

centrally acting antimuscarinics used in Parkinson’s/drug-ind. Parkinsonism tx

185
Q

Tolterodine (Detrol)
Oxbutynin (Ditropan)
Solifenacin (VESIcare)

A

antimuscarinics, tx of urinary incontinence due to overactive bladder

186
Q

Tropicamide (Midriacyl)

A

antimuscarinic used to dilate pupil for examination

187
Q

first gen H1 antagonists: v. sedating antihistamines

A
Promethazine hydrochloride (Phenergan)
Hydroxyzine (Vistaril)
188
Q

first gen H1 antagonists: sedating antihistamines

A
Diphenhydramine (Benadryl)
Dimenhydrinate (Dramamine)
Doxylamine (Unisom)
Chorpheniramine maleate (Chlor-Trimeton)
Meclizine (Bonine, Antivert)
189
Q

second gen H1 antagonists: non-sedating antihistamines

A

Loratadine (Claritin, Alavert)/Desloratidine (Clarinex)
Certirizine (Zyrtec) and Levocetirizine (Xyzal)
Fexofenadine (Allegra)

190
Q

H2 antagonists

A

Cimetidine (Tagamet)
Ranitidine (Zantac)
Famotidine (Pepcid)
Nizatidine (Axid)

191
Q

histamine functions

A

mediates phys. resp to tissue/cell injury
mediates inflamm. resp/allergic reactions
reg. cell growth/repair
reg. gastric acid sec
NT in CNS
pos. reg. of cardiac functions

192
Q

histamine syn

A

syn from histidine by histidine decarboxylase

193
Q

histamine metab

A

involved N-methylation–>oxidation to N-methylimidazole acetic acid

194
Q

histamine storage

A

mast cells and basophils
skin and mucosa of GI and resp tracts
IC histamine stored in granules, loosely bound to proteoglycans like heparin sulfate or chondroitin sulfate

195
Q

histamine release: drug/chem induced

A
  • displaced by amine drugs (morphine, tubocurarine, B-blockers)
  • compound 48/80
  • toxins and venoms
196
Q

histamine release may released in response to

A

cell/tissue damage

197
Q

histamine release: immunologic stimulation

A

mast cells sensitized w/ IgE Abs–>rel. histamine when exposed to approp. allergen
-other autocoids syn or del: PGs, LKTs, kinins (bradykinin)

198
Q

histamine release: neuronal and endocrine stimulation

A

gastric mucosa: rel in resp to neuronal (vagal)/endocrine stim (gastrin)
-neuronal med. by ACh
-the histamine binds to H2 rec on parietal cells–>HCl sec–>permissive effect, allows gastrin and acetyl choline to directly stim. acid secretion
(H2 rec ANTAGONISTS are effective in red. sec of gastric acid in response to histamine, vagal stim, ACh, or gastrin)

199
Q

physio effects of histamine

A
  • dil of small BVs–>flushing, lowered peripheral resistance, drop in BP
  • inc. in cap perm–>leakage of fluid and prot. into extravascular space
  • stimulation of peripheral nerve endings–>pain, burning, itching
200
Q

physio effects of histamine: triple response

A
  • red spot (dil. of minute BVs)
  • flare (dil. of neighboring arterioles)
  • wheal (inc. cap permeability)
201
Q

physio effects of histamine: histamine shock

A

vasodilation and fluid leakage into EV space–>sig. drop of BP (resembles traumatic, septic, or hemorrhagic shock)

202
Q

physio effects of histamine: bronchial constriction

A

asthmatic and anaphylactic bronchospasm
-not completely dep. on histamine, so not effectively antag. by antihistamines alone (use sympathomimetic drugs, methylaxanthines)

203
Q

physio effects of histamine: stimulation of gastric acid secretion

A

in response to stress, vagal stim, gastrin and cholinergic agonists
-mediated by H2 rec. (blocking these red. stomach acid sec.)

204
Q

physio effects of histamine: cerebral vessels and histamine

A

-v. sens to histamine!–>intense diation–>pulsatory HA (stretching of sensory nerve endings-histamine cephalgia)
(attempt to antag H1 and H2 rec, little success)

205
Q

physio effects of histamine: direct effects on heart

A

inc. force of contraction

slowing of AV conduction

206
Q

H1 receptor

A
  • skin, BVs, heart, airway, CNS

- mediate rapid vasodil., inc. cap perm, irritation of peripheral nerve endings, bronchoconstriction

207
Q

H1 receptor blockers/histamine antagonists

A

“antihistamines”, tx allergies, rhinitis

actually inverse agonists: red. activity of constitutively act. H1 rec.

208
Q

H2 receptor

A
  • GI, heart, brain, various BVs

- mediated gastric acid secretion

209
Q

H2 receptor blockers

A
  • reduce gastric acid sec. (peptic ulcer disease)

- may be used to tx histamine-induced symps of Type 1 immediate hypersensitivity rxns (urticaria)

210
Q

H3 receptors

A
  • CNS
  • presyn. autoreceptors to reg rel of histamine as NT (like alpha adrenergic rec?)
  • no sp. drugs for clinic use (potentials: sleep/mood disorders, Alzheimer’s disease)
211
Q

H4 receptors

A
  • hematopoetic cells

- unclear, inflammation

212
Q

therapeutic uses of histamine

A

few

dx tests for allergies, asthma, and sensory nerve function

213
Q

structure of antihistaminic drugs: H1

A

lipophilic ring structure + charged side chain amino group

214
Q

structure of antihistaminic drugs: H2

A

hydrophilic ring structure + uncharged side chain

215
Q

1st gen H1 antagonists: v. sedating

A
Promethazine hydrochloride (Phenergan)
Hydroxyzine (Vistaril)
216
Q

1st gen H1 antagonists: sedating

A
Diphenhydramine (Benadryl)
Dimenhydrinate (Dramamine)
Doxylamine (Unisom)
Chlorpheniramine maleate (Chlor-Trimeton)
Meclizine (Bonine, Antivert)
217
Q

2nd gen H1 antagonists: non-sedating

A

Loratadine (Claritin, Alavert)/Desloratidine (Clarinex)
Certirizine (Zyrtec)/ Levocetirizine (Xyzal)
Fexofenadine (Allegra)

218
Q

H1 antagonist pharm effects

A

occupy H1 rec w/out prod/initiating active response (competitive antagonism) OR inverse agonism

  • reduce pain, itch, flare, vasodilation, inc. vasc. perm (red), congestion
  • DO NOT prevent release of histamine/other inflamm/allerg mediators
  • DO NOT reverse anaphylactic bronchospasm
219
Q

uses of H1 antihistamine: allergy tx

A

hay fever (seasonal) rhinitis
relief of sneezing, wheezing, eye/nose/throat itch, rhinorrhea
certain allergic dermatitis (urticaria) (i.e. diphenhydramine in “anti-itch” topical meds)

220
Q

alone, H1 antihistamines are NOT effective in..

A

anaphylaxix, angioedema, asthma

*bronchospasm may be life threatening, should be tx w/ epinephrine or other B-agonists, H1 antihist can be adjunct

221
Q

uses of H1 antihistamine: common cold tx

A

alleviate nasal irritation (burning, itching, “runny nose”)

DO NOT alter course of cold

222
Q

uses of H1 antihistamine: antiemetics

A

(dimenhydrinate, meclinzine): prevent and tx motion sickness/vertigo

(doxylamine) : sometimes to tx N/V during pregnancy
- may be more general anti emetics (3 above + hydroxyzine)

223
Q

uses of H1 antihistamines: sedative and sleep aids

A
  • night time cold remedies (Nyquil) and sleep aids
  • Hydroxyzine (Atarax: Vistaril): sedatives
  • Diphenhydramine, doxylamine: OTC sleep aids
224
Q

uses of H1 antihistamines: antisecretory agents

A

(diphenhydramine) used in pulmonary medicine (tracheostomy care, etc)

225
Q

uses of H1 antihistamines: Parkinsonism tx

A

anticholinergic activity (diphenhydramine)

226
Q

side effects/toxicities of H1 antihistamines

A

anticholinergic: dry mouth, dry/hot skin, constipation, urine retention, loss of visual accomm. etc.
sedation drowsiness, confusion, amnesia, behavioral disturbances occur at common therapeutic doses
*may be more pronounced in elderly
*2nd gen (loratidine, fexofenadine, ceirizine) less CNS effects and sedation

227
Q

more side effects/toxicities of H1 antihistamines

A
  • paradox. CNS stim in some (esp. kids)
  • reported teratogenic effects (doxylamine story)
  • allergic rxns (topical use)
  • lowers seizure threshold
  • serious arrhythmias (Astemizole, terfenadine -w/drawn)
228
Q

even more side effects/toxicities of H1 antihistamines

A

-acute poisoning/OD (kids esp):
symptoms like atropine poisoning: excitation, halluc., ataxia, uncoordination, convulsion, musc tremors, uncontrollagle clonic/tonic jerky motions, fixed dil. pupils, flushed face, fever, coma, cardio-resp collapse and death
tx: symptomatic: cholinesterase inhibitors (physostigmine), anti-seizure, CV meds as needed

229
Q

antihistamine pharmacokinetics: admin

A

oral*, parenteral, topical
oral:
onset: 15-30 min, pk: 1 hour, duration 3-6 hours
degraded in body, excr. w/in 24 hours
*no cumulative effect if liver/kidneys are functional

230
Q

2nd gen antihistamine pharmkin.

A

DO NOT cross BBB, do not cause sedation

longer durations of action (about 24 hrs), long 1/2 lives: wk+ to reach steady state

231
Q

antihistamine drug interactions

A
  • potentiates CNS depressants, etOH, barbs, opioids, benzos
  • arrhythmias (torsades de pointes) in pts taking terfenadine or astemizole (metab by P450: CYP3A4 to active drug) w/ erythromycin, ketoconazole, or itraconazole
  • the antihist. prodrug can block K+ channels in heart, not all prodrug broken down when taken w/ other drugs metabolized by CYP3A4
  • both terfenadine (Seldane) and astemizole (Hismanal) w/drawn (Allegra, flexofenadine) is active metab of terfenadine
232
Q

antihistamines can interfere w.

A

allergy testing, must stop antihistamine 5-7 days before testing

233
Q

antihistamine combo preps

A

in cold, cough, allergy remedies

-decongestants, analgesics, antitussives, etOH, w/ the antihistamine

234
Q

H2 histamine antagonists summary

A

comp. antags at H2 rec

tx for peptic ulcer disease

235
Q

H2 histamine antagonists

A

Cimetidine (Tagamet)* cytP450 metab., anti-androgen
Ranitidine (Zantac)
Famotidine (Pepcid)
Nizatidine (Axid)

236
Q

H2 histamine antagonist pharm effects

A
  • inhib gastric acid secretion (stim. by histamine) in response to:
  • vagal stimulation (ACh)
  • gastrin secretion (ZES: tumor)
  • stress
237
Q

H2 histamine antagonists tx

A
  • duodenal/gastric ulcers
  • gastroesophageal reflux
  • ZES
  • pre-op to lessen aspiration damage
  • prevent stress ulcers
238
Q

H2 histamine antagonist adverse rxns

A

(low: highly selective @ H2 rec)
- HA, dizzy, nausea, myalgia, skin rashes/itching (elderly, renal dysfunction)
- loss of libido, impotence, gynecomastia (chronic high does of Cimetidine–>can tx hirsutism)
- Cimetidine also can cause hematological rxns (cytopenias) and competes w. creatinine for renal secretion (inc. plasma conc. creatinine)

239
Q

H2 antagonist pharmkin

A
  • oral admin–>well absorbed
  • 1/2 lives about 2-4 hrs
  • also injectable: cimetidine, ranitidine, famotidine
  • metab by liver (cimetidine can inhib cytP450 and interfere w. metab of other drugs)
  • sig. amounts excr unchanged in urine (adj. dose in renal disease pts.)
240
Q

H2 antagonist drug interactions

A

Cimetidine: inhib hep microsomal drug metab enzymes:
warfarin, phenytoin, theophylline, phenobarbital, benzos, propranolol, nifedepine, digoxin, quinidine, tricyclic antidepressants
(Famotidine and nizatidine do not inhib P450 system, ranitidine has slight effect, not sig.)
-H2 blockers alter gastric pH: alter bioavailability of certain drugs

241
Q

H2 antagonist therapeutic uses

A

gastric/duodenal ulcers, ZES, stress ulcers, reflux esophagitis, short bowel syndderom, hypersec. states (ZES), preanesthetic meds

  • typ. not frontline drugs, PPIs used more commonly
  • *cimetidine is most widely used, but potential for most side effects/drug interactions
242
Q

CRTZ

A

-floor of 4th ventricle, area postrema
-vomiting assoc. w. exposure to drugs, metabolic toxins, chemotherapy, radiation, changes in blood chemistry
NTs: DA, 5HT (serotonin) so tx w/ DA/serotonin antagonists
Dopamine antagonists: tx CRTZ induced N/V, NOT motion sickness/vertigo

243
Q

serotonin also

A

NT action: is released by enterochromafin cells of GI tracts when GI distress (5-HT3 rec blockers prevent N/V)

244
Q

vestibular apparatus and cerebellum

A

respond to motion (or “perceived” motion)
NTs: ACh and possibly histamine (inhibitors tx)
anticholinergics/antihistamines: tx motion sickness, vertigo NOT other causes of N/V (antihist. have some effect on CRTZ and vomiting center, but less eff. than DA antags)

245
Q

cerebral cortex and limbic system:

A

vomiting ref. activated by emotional state (can be consciously suppressed): anxiolytic agents

246
Q

efferent component of reflex

A

output from vomiting center–>salivary glands, stomach, sm. intestine, diaphragm, abd. mm

247
Q

anticholinergic agents for nausea

A

Scopolamine

  • acts on vestibular system, tx/prevents vertigo/motion sickness
  • gen. effects on CRTZ, not as effective as DA, 5-HT untags
  • Transderm Scop preperation
248
Q

Scopolamine side effects/toxicity

A
  • antichol. effects: dry mouth, constip, urinary retention, loss of accomm.
  • sedation, confusion, amnesia
249
Q

antihistamine for N/V effects

A
  • primarily on vestibular, some have weak effects on CRTZ or vomiting center (cyclizine, doxylamine, meclizine, promethazine, hydroxyzine) (b/c of antichol. activity?)
  • tx for motion sickness/vertigo
  • some for gen. antiemetic (cyclizine, meclizine, promethazine, hydroxyzine)
250
Q

antihistamine side effects/toxicity

A

antichol. effects, sedation, teratogen effects?

251
Q

antihistamines for N/V

A
dimenhydrinate (Dramamine)
meclizine (Bonine, Antivert)
promethazine (Phenergan)
diphenhydramine (Benadryl)
doxylamine (Bendectine: teratogen? no-->now Diclegis)
252
Q

Dopamine (D2) antagonists action

A

acts on CRTZ, tx:

postop nausea, cytotoxic drugs, radiation sickness, toxins

253
Q

DA (D2) antagonist side effects/toxicity

A

parkinsonism (blocks striatum), post. hypotension, anticholinergic effects, sedation, lethargy, psychomotor slowing (antipsychotics), possible teratogen

254
Q

D2 antagonists for N/V

A

prochlorperazine (Compazine) -phenothiazine

metoclopramide (Reglan)

255
Q

metoclopramide (Reglan) for N/V

A

DA antag in CRTZ but also acts on enteric nerves to inc. GI/lower eso. sphincter tone and motility

tx: N/V from chemo, postop, toxin-induced, radiation
tx: gastric stasis, GERD, possible aspiration of vomitus

256
Q

metoclopramide (Reglan) side effects

A

sedation, extrapyramidal motor problems: parkinsonism and acute dystonia

257
Q

5-HT3 antagonists (serotonin) for N/V

A

ondansetron (Zofran)
granisetron (Kytril)
dolasetron (Anzmet)

258
Q

5-HT3 antagonist actions

A

tx: N/V from chemo, postop; effective in about 80% pts
- depress CRTZ and inhib serotonin mediated afferent input from GI tract
- may be given orally/IV, metab by hepatic microsomal enzymes (drug interactions)
- adverse effects: HA, constipation

259
Q

cannabinoids for N/V

A

dronabinol (Marinol): d-9-THC (marijuana)
-oral oil capsule
tx for N/V in chemo (back-up drug), prevent wasting “kekexia” in AIDS pts.
*smoking may be more effective than oral, bypass liver and produces combustion products

260
Q

cannabinoid side effects

A

sedation, confusion, disorientation, loss of control, alt. sensations, paranoia, psychotic rxns (not tol. well in some esp. elderly)

261
Q

corticosteroids for N/V

A

dexamethasone, prednisone, methylprednisolone

-adj. antiemetics in chemo regimens

262
Q

P/neurokinin rec (NK1) antagonist for N/V

A

aprepitant (Emend)

tx: N/V from chemo, v. expensive, not 1st line

263
Q

pyridoxine (vit B6) and doxylamine

A

Bendectine: terotogen scare in 80’s–>unfounded–>now Diclegis (2013) for N/V during pregnancy

264
Q

amphetamine

A
  • some benefits in preventing motion sickness, can counteract sedative effects of other drugs
  • not typ. used: CNS effects, abuse potential
265
Q

other antiemetics

A
  • phosphorylated carb. solutions (Emetrol), cola syrups
  • antimicrobial agents
  • antianxiety drugs: benzos for N/V from fear, anxiety
  • ginger
266
Q

antiemetics for motion sickness/vertigo

A

antihistamines, anticholinergics

267
Q

antiemetics for postop

A

DA or 5-HT3 antagonists

268
Q

antiemetics for radiation sickness

A

DA antagonists

269
Q

antiemetics for drug-induced vomiting

A

DA / 5-HT3 antagonists, cannabinoids

270
Q

antiemetics for pregnancy

A

try to avoid drugs, diet modification

pyridoxine +/- doxylamine–>antihistamine–>DA antagonist (avoid 5-HT3 antagonists)

271
Q

cough reflex controlled by….
receives input from..
responds to..

A

cough control center
input from pharynx, larynx, airway, lungs
stretch (distension), presence of particulate matter, chem. irritation

272
Q

afferent impulses from receptors sent to cough control center via

A

glossopharyngeal and vagus nn.

273
Q

efferent component of cough reflex

A

epiglottis, pharynx, larynx, lungs, diaphragm, mm. of thorax/abdomen
-cough mech can be activated and suppressed (to some extent) consciously

274
Q

rationale for antitussive therapy

A
  • remove cause of irritant
  • inc. airway sec. to mobilize irritants (expectorant)
  • desens. peripheral rec.
  • act on CNS component
275
Q

antitussives that act on cough control center: opioids

A

codeine, hydrocodone, etc.

  • prob. most effective, given at lower doses than for pain
  • side effects: sedation, lightheaded, confusion, nausea, dizzy, constipation, abuse, physical dependence
276
Q

antitussives that act on cough control center: non-opioids

A

dextromethorphan (syn. analog of levorphanol)
-effective as codeine for mild-mod cough, not as eff. for severe cough
-block NMDA rec
side effects: mild; sedation, dizzy confusion
-no analgesic effects, lower abuse potential

277
Q

non-opioid antitussives

A

dextromethorphan:
Benylin DM, Pertussin, Vicks Formula 44, etc. OTC
*may be abused in higher doses (kids, i.e. cough syrup)

278
Q

agents that act on airway receptors

A

benzonatate (Tessalon):
-local anesthetic, desens. airway receptors
-some effect on CCC, capsule for oral use
-side effects: mild: constipation, nasal cong., nausea, drowsiness, rashes
menthol (in many preps)

279
Q

antitussives: expectorants

A

guaifenesin: questionable efficacy

mild irritants in GI tract–>activates reflex–>inc. mucus production in airway

280
Q

antitussives: mucolytic agents

A

acetylcysteine (Mucomyst) (nebulization)

disrupts disulfide linkages–>inc. mucus viscosity, breaks mucus plugs–>easier to mobilize, humidifies air

281
Q

antitussives: mucolytic agents tx

A

postop, tracheotomy care, sever bronchitis, emphysema

*antidote in Tylenol (acetaminophen) poisoning (Acetadote)

282
Q

antitussives: antihistamines

A

diphenhydramine, promethazine, etc (in many cough/cold remedies)
-antag effects of histamine–>dec. irritation/constriction of airway–>also sedation and weak effects on CCC

283
Q

antitussives: bronchodilators

A

dec. airway resistance (asthma)

284
Q

antitussives: demulcents

A

“syrupy” materials that exert coating and soothing action (cough preps)

285
Q

should cough be tx?

A
  • cough is useful if productive

- tx in pts w/ hernias, CV probs, postop/trauma

286
Q

mild-mod cough tx

A

dextromethorphan

287
Q

severe cough tx

A

codeine (or other opioid)

288
Q

if overly productive cough, consider a prep with

A

antihistamine

289
Q

antitussives may be combo of

A

antihistamines, expectorants, decongestants, acetaminophen, etOH

290
Q

direct acting sympathomimetics (adr. rec agonists): mixed, nonselective agonists

A

epinephrine (adrenalin, EpiPen, Auvi-Q)
NE (Levophed)
Isoproterenol (Isuprel)
DA (Intropin)

291
Q

selective B1 agonists

A

dobutamine (Dobutrex)

292
Q

selective B2 agonists

A
albuterol (Proventil)
Metaproterenol 
Pirbuterol (Maxair)
Salmeterol (Serevent)
Terbutaline
293
Q

selective B3 agonists

A

Mirabegron (Myrbetriq)

Solabegron

294
Q

selective a1 agonists

A
phenylephrine
midodrine (ProAmantine)
295
Q

indirect-acting sympathomimetics (next exam?)

A

cocaine
pseudoephedrine (Sudafed) ephedrine
amphetamine and methamphetamine
methylphenidate (Ritalin)

296
Q

NE and E released from

A
adrenal medulla (E>NE)
pheochromocytoma cells (NE>=E)
297
Q

pheochromocytomas tx w.

A

metyrosine: sp. tyrosine hydroxylase inhibitor

298
Q

extrasynaptic receptors

A

a2, B2

activated pref. by circulating NE > NE from nerve endings

299
Q

intrasynaptic receptors

A

a1, B1
activated by NE from nerve endings, would need ^^^ conc. circ. NE to be stimulated
more intra>extrasynptic receptors
(narrow syn. space, reuptake pump)

300
Q

inactivation of NE or E

A

MAO–>deaminated metabolites
COMT–>O-methylated metabolites
Vanillylmandelic acid (VMA) is a deaminated AND o-methylated metabolite

301
Q

high urine levels of these are dx for pheochromocytoma

A

metanephrines and/or VMA

302
Q

pts on these meds will experience more intense effects of symp. drugs

A

MAO inhibitors

303
Q

these vessels typ. do not become highly constricted during sympathetic activity (a rec. agonist admin)

A

coronary and cerebral vasc. smooth muscle

fewer in #, receive less symp. neural traffic, powerful authoreg. capabilities

304
Q

dopamine receptors are present here to mediate vasodilation

A

renal and other splanchnic (gut) beds

305
Q

normal resting symp. nerve activity is

A

10-20% of max
-maintains BP, body temp
(i.e. spinal anesthesia–>drop in art. pressure–>restored w/ NE
can be altered by brain centers receiving info from sens. afferent neurons from baroreceptors and thermoreceptors

306
Q

baroreceptors

A

in carotid arteries and aortic arch
sense small changes in mean BP–>changes ANS outflow from CNS vasomotor centers to the vessels (symp) and heart (symp + PS) to correct BP changes

307
Q

inc in SNA to lower body vv imp. to..

A

prevent venous pooling during orthostasis, helps maintain art. perfusion pressure

308
Q

thermoreceptors

A

brain, skin, etc.

  • redistrib. SNA to surface + core vessels in response to temp changes
  • also: brain tells adrenomedulla–>rel. more E to inc. glucose output (hep. cells) and FFA output for thermogenesis (also triggered by exercise and hypoglycemia)–>HR will inc.
309
Q

abnormally excessive symp. NE response to cold stress can lead to

A

Raynaud’s disease

310
Q

epinephrine stimulates

A

ALL receptors nearly alike: a1, a2, B1, B2

311
Q

low IV rates of E stimulate

A

extrasynaptic rec (a2, B2): dec. in diastolic and increase systolic, PP, and HR (MAP unchanged)

312
Q

higher IV rates of E stimulate

A

intrasynp. rec as well (a1, B1 as well as a2, B2): inc. PP, inc. diastolic and systolic, inc. MAP

313
Q

E used in circulatory shock

A

tx bronchospasm and circ. collapse from anaphylactic shock

-high systemic dose, multi. rec stim: bronchial B2, vascular a, cardiac ventricular B

314
Q

low, local E used to tx

A

asthma: bronchial B2

cardiac arrest: high systemic (cardiac B, vascular a) accomp. CPR, e-stim

315
Q

high, systemic E used to tx

A

cardiac arrest: (cardiac B, vascular a) accomp. CPR, e-stim

316
Q

E also tx bradycardia

A

high doses for A-V block (AV node B and/or purkinje fiber B) until pacemaker insertion
low doses for non-A-V block bradycardias, so MAP is not increased (SA node B2)

317
Q

E can also be mixed w.

A

local anesthetics; prolongs action at local inj. sites, min. syst. toxicity and local bleeding
*high local conc. to stim. all vascular a rec.

318
Q

NE stimulates these rec

A

a1, a2, B1 (not B2)

319
Q

both low and high doses of NE..

A

increase all pressures

320
Q

NE reflexively

A

DECREASES HR

321
Q

most uses of NE due to effects on

A

vascular a rec.

322
Q

NE used in

A

shock: i.e. cardiogenic and neurogenic: stim cardiac B1 and/or vascular a rec
and early septic shock: esp. when shock persist after fluid replacement (vasc. a)

323
Q

NE supports BP during

A

spinal anethesia

324
Q

NE could be used w.

A

anesthetics (like E) (this use discontinued)

325
Q

Isoproterenol stimulates these rec

A

B1, B2 (NOT a)

326
Q

both low and high doses Iso..

A

dec. diastolic and MAP

inc. PP and HR

327
Q

Iso was rec. removed from use as

A

a bronchodilator, but longer action than epi

328
Q

Iso tx this when other tx fail

A

bradyarrhythmias (cardiac B)

329
Q

Iso used as

A

“pharmacologic provocation” med. alternative to tilt-table test to dx unexplained syncope (vasovagal) (cardiac ventricular B)

330
Q

diastolic pressure reflects

A

total peripheral resistance

331
Q

mean pressure is

A

a rough average of sys and dias pressure

332
Q

control of HR may be affected by barorec. as well as

A

direct stimulation of rec in SA node

333
Q

pulse pressure reflects

A

left ventricular cardiac contractility

334
Q

systolic pressure =

A

diastolic + pulse pressure

335
Q

Dopamine (DA) stimulates

A

DA receptors>B1>a1

336
Q

low doses DA stimulates

A

DA rec in splanchnic regions like GI and renal art. smooth muscle: inc. blood flow here

337
Q

intermediate doses DA stim

A

B1 rec: cardiac contractility and rate (as well as DA)

338
Q

high doses DA stim

A

a1 rec: may blunt effects of DA on splanchnic/kidney art. sm musc. (constricts)–>stim of all other vasc. a1–>rise in MAP due to increase in TPR

339
Q

DA used in shock

A

cardiogenic and neurogenic (B1 +/- a1)

early or late septic shock

340
Q

DA also used in..

A

CHF (w/ other tx failure) (cardiac B1 +/- renal D)

-controversial

341
Q

DA for bradycardia

A

in pts. unrespon. to other tx

-desirable to stim. B1 not a1 so inc. HR w/out inc. MAP(would cause reflex bradycardia)

342
Q

selective B1 agonist

A

Dobutamine (+a1 agonist or a1 antag + B1 agonist)
-inc. cardiac contractility, rate–>inc. CO, PP
(not much inc. in diastolic and MAP)

343
Q

Doputamine used for

A

CHF

shock (cardiogen, late phase septic) (only B1)

344
Q

IMPORTANT use of Doputamine

A

stimulate the heart during emergence from heart surgery

345
Q

selective B2 agonists used as

A

bronchodilators (“rescue” inhalers) for COPD, asthma
post-exercise-induced bronchospasms
(oral, IV, inhaled)

346
Q

terbutaline (B2 agonist) used to manage

A

premature labor: B2-mediated uterine relaxation (not. rec. for prolonged use, risk of CV effects)

347
Q

selective B3 agonists

A

Mirabegron and Solabegron

tx for over-active bladder, relaxes detrusor sm. musc (relax to keep urine in)

348
Q

tx anaphylactic shock w/

A

epinephrine 1st: high systemic dose

349
Q

cardiogenic shock usually caused by

A

sig. loss of left ventricular musc. contractile function (post-acute MI)
- ->dec. CO, resistance may inc., pressures still fall

350
Q

tx cardiogenic shock w/

A

NE, DA, and/or dobutamine (support circulation)

-B just for heart or a to support diastolic pressure btw contractions

351
Q

tx neurogenic shock w/

A

NE, DA, phenylephrine

heart, BVs, or both?

352
Q

septic shock typ. involves

A

G- bacteria, endotoxins

353
Q

2 phases of septic shock

A

warm phase, cold phase

354
Q

warm phase of septic shock

A

dec. syst. resistance–>massive systemic dilation–>art. pressure falls
tx: NE and/or vasoconstrictor (a1-stim) dose of DA (or phenylephrine)

355
Q

cold phase of septic shock

A

1-2 days later
myocardial depression–>low CO–>low art pressure
vasc. resistance may go up (high SNA)
tx: DA (not high vasc. a1-stim level), dobutamine to reverse low CO

356
Q

late phase septic shock

A

involves inadeq. perf. of vital vasc. beds
mesenteric/renal circ. compromise
tx: low dose DA (acts on D rec) can improve flow to those regions (vasodil)

357
Q

effects of HIGH IV epinephrine infusion

A

all pressures go up, enough a1, a2 constriction to overcome B2 vasodilation (in contrast to low epi dose, diastolic goes down due to vasc B2 rec not opposed enough by a rec-vasoconstriction)
-inc. in pulse pressure: left ventr. B1 rec. are stim. along w/ B2 rec.

Decks in Micro Class (61):