Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

NAPLEX 2024 > 3. Drug Interactions > Flashcards

3. Drug Interactions Flashcards

1
Q

Concomitant use of benzodiazepines and opioids may result in ___, ___, ___, and death d/t additive effects

A

profound sedation, respiratory depression, coma, and death

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

Which drugs have concern for chelation and should be separated from polyvalent cations or other drugs with binding properties (e.g. antacids, multivitamins, sucralfate, bile acid resins, Al, Ca, Fe, Mg, Zinc, phosphate binders)

A

Quinolones, tetracyclines, levothyroxine, and oral bisphosphonates

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

CYP___ metabolizes ~34% of all CYP450 drug substrates

A

3A4

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

What is the active metabolite of capecitabine?

A

Fluorouracil

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

What is the active metabolite of clopidogrel?

A

Active metabolite

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

What is the active metabolite of Codeine?

A

Morphine

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

What is the active metabolite of colistimethate?

A

Colistin

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

What is the active metabolite of coristone?

A

Cortisol

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

What is the active metabolite of Famciclovir?

A

Penciclovir

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

What is the active metabolite of fosphenytoin?

A

Phenytoin

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

What is the active metabolite of isavuconazonium sulfate?

A

Isavuconazole

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

What is the active metabolite of levodopa?

A

Dopamine

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

What is the active metabolite of Lisdexamfetamine?

A

Dextroamphetamine

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

What is the active metabolite of Prednisone?

A

Prednisolone

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

What is the active metabolite of Primidone?

A

Phenobarbital

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

What is the active metabolite of Tramadol?

A

active metabolite

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

What is the active metabolite of Valacyclovir?

A

Acyclovir

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

What is the active metabolite of valganciclovir?

A

ganciclovir

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

Codeine is metabolized by ____. What is the risk of use in pts who are ultrametabolizers (UM)?

A

2D6
Risk of toxicity (rapid conversion to morphine) - do not use

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

Codeine is metabolized by ____. What is the risk of use in pts who are poor metabolizers (PMs)?

A

2D6
Risk of poor analgesia effect - use alternative

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

Clopidogrel is metabolized by ____. What is the risk of use with inhibitors? Give 2 examples

A

2C19
Inhibitors will block conversion to active form - do NOT use with CYP2C19 inhibitors, including omeprazole and esomeprazole (can decrease antiplatelet effects)

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

Clopidogrel is metabolized by ____. What is the risk of use in pts who are poor metabolizers (PMs)?

A

2C19
Lower conversion to active form, reduced antiplatelet activity - use alternative P2Y12 inhibitor in pts who are PM

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

Are CYP450 enzymes involved in phase I or phase II reactions?

A

Phase IW

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

What are some examples of phase II enzymes?

A

Uridine diphosphate glucuronosyltransferase (UGT)
N-acetyltransferase (NAT)

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

___ (a phase II enzyme) are highly polymorphic; differences in the degree of isoniazid toxicity were found to be d/t differences in the rate of acetylation by this enzyme

A

N-acetyltransferase (NAT)

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

What are some moderate or strong CYP3A4i examples? (Hint: mneumonic)

A

G <3 PACMAN

Grapefruit
<3
Protease inhibitors (esp ritonavir)
Azole antifungals (fluconazole, itraconazole, ketoconazole, posaconazole, voriconazole, and isavuconazonium)
Cyclosporine, cobicistat
Macrolides (clarithromycin and erythromycin but NOT azithromycin)
Amiodarone, dronedarone
Non-DHP CCBs (diltiazem and verapamil)

Note: Amiodarone has ability to inhibit multiple CYP enzymes (e.g. 3A4, 2C9, 1A2)

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

What are some moderate or strong CYP3A4 inducers examples? (Hint: mneumonic)

A

PS PORCS

Phenytoin
Smoking
Phenobarbital
Oxcarbazepine
Rifampin, rifabutin, rifapentine
Carbamazepine (also an auto-inducer)
St. John’s wort

Note: Rifampin has ability to inhibit multiple CYP enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

T/F: enzyme inhibition effects take 2-4 weeks

A

False - enzyme INDUCTION often requires additional enzyme production, which take times, may take up to 4 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

When inducer is stopped, it could take ___ for the induction effects to disappear completely

A

2-4 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Do P-gp efflux pumps in the cell membranes of the GI tract pump drugs and their metabolites into or out of the gut?

A

They pump INTO the gut to be excreted in the stool

Efflux = to flow out (but in this case out of the body, so pump INTO gut to get OUT of body)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

When a drug inhibits P-gp, a P-gp substrate will have (increased/decreased) absorption and the substrate drug level will (increased/decrease)

A

increased absorption
increased drug level

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Common P-gp substrates

A

Anticoagulants (apixaban, rivaroxaban // edoxaban, dabigatran)
CV drugs (digoxin, diltiazem, verapamil // carvedilol, ranolazine)
Immunosuppressants (cyclosporin, tacrolimus // sirolimus)
HCV drugs (sofosbuvir)
Others (colchicine // atazanavir, dolutegravir, posaconazole, raltegravir, saxagliptin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Common P-gp inducers

A

Carbamazepine, phenobarbital, phenytoin, rifampin, St. John’s wort
Others: dexamethasone, tipranavir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Common P-gp inhibitors

A

Anti-infectives (clarithromycin, itraconazole, posaconazole)
CV drugs (amiodarone, diltiazem, verapamil // carvedilol, conivaptan, dronedarone, quinidine)
HIV drugs (cobicistat, ritonavir)
HCV drugs (ledipasvir)
Others (cyclosporine // flibanserin, ticagrelor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Which 3A4 inducers are also p-gp inducers (from mneumonic PS PORCS)

A

Phenytoin
Phenobarbital
Rifampin
Carbamazepine
St. John’s Wort

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Which 3A4 inhibitors are also p-gp inhibitors (from mnuemonic G<3PACMAN)

A

Protease inhibitor = ritonavir
Azole inhibitors (itraconazole, posaconazole)
Cyclosporin, cobicistat
Macrolide (clarithromycin)
Amiodarone
Non-DHP CCBs (diltiazem, verapamil)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the DDI between amiodarone and warfarin?

A

Amiodarone inhibits multiple enzymes include CYP2C9, which metabolizes more potent warfarin isomer (decrease warfarin metabolism = increase INR and bleeding risk)

If amiodarone (1st) + warfarin - start warfarin at lower dose
If warfarin (1st) + amiodarone - decrease warfarin dose 30-50% depending on INR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Which drug needs to be decreased by 30-50% if starting amiodarone?

A

Warfarin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is the DDI between amiodarone and digoxin?

A

Amiodarone inhibits P-gp
Digoxin is P-gp substrate
Decreased digoxin excretion, increased ADRs/toxicity
Amiodarone and digoxin both decrease HR, increase bradycardia, arrhythmia, fatality

If amiodarone (1st) + digoxin - start digoxin at lower dose
If using digoxin (1st) + amiodarone - lower PO digoxin dose 50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Which drug needs to be decreased by 50% if starting amiodarone?

A

Digoxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

If taking both amiodarone and digoxin, what are some other drugs to be careful of?

A

Drugs that decrease HR
beta-blockers, clonidine, diltiazem, verapamil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is the DDI between digoxin and loop diuretics?

A

Loop diuretics decrease K, Mg, Ca, and Na (low K, Mg, or Ca will worsen arrhythmias)
Digoxin toxicity risk is increased with decrease K and Mg levels and increased Ca levels

Caution: HF and renal failure often occur together. Digoxin is cleared by P-gp and excreted by kidneys = renal impairment increase digoxin levels and toxicity risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is the concern of concomitant use of drugs that decrease HR?

A

Additive effects
Caution: amiodarone, digoxin, beta-blockers, clonidine, diltiazem, verapamil and dexmedetomidine (Precedex)
Monitor HR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is the DDI between statins and strong CYP3A4 inhibitors (G PACMAN)?

A

Increased levels of CYP3A4 substrates: lovastatin, simvastatin, atorvastatin
Higher risk of myopathy, rhabdo risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Which statins are contraindicated with strong CYP3A4 inhibitors (G PACMAN)?

A

Simvastatin and lovastatin
Recommend a statin not metabolized by CYP450 enzymes like pitavastatin, pravastatin, and rosuvastatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Which statins are NOT metabolized by CYP450 enzymes?

A

pitavastatin, pravastatin, and rosuvastatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What is the DDI between warfarin and CYP2C9 inhibitors? (azole antifungals, SMX/TMP, amiodarone, metronidazole)

A

Increase levels of warfarin (increase INR = increase bleeding risk)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is the DDI between warfarin and CYP2C9 inducers? (rifampin, St. John’s wort)

A

Decrease levels of warfarin (decrease INR = increase clotting risk)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Which opioids are CYP3A4 substrates?

A

fentanyl, hydrocodone, oxycodone, and methadone
Do NOT use CYP3A4 inhibitor with opioid metabolized by CYP3A4 - icnreased ADRs, including sedation, may be fatal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Which drugs should not be taken with grapefruit/ grapefruit juice?

A

Do NOT take with CYP3A4 substrates: amiodarone, simvastatin, lovastatin, nifedipine, and tacrolimus (others have similar risk)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is the DDI between valproate and lamotrigine?

A

Valproate decreases lamotrigine metabolism
Increased lamotrigine = increase risk of serious skin reactions (SJS/TEN), can be fatal

Use starter kit (lower lamotrigine doses) and titrate carefully every 2 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

If using valproate and lamotrigine together, what should pharmacists recommend?

A

Initiate lamotrigine using the starter kit that begins with lower lamotrigine doses, titrate carefully every 2 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is the DDI between MAOi and drugs that increase Epi, Ne, DA, or 5-HT?

A

MAO enzyme metabolizes Epi, NE, DA, tyramine, and 5-HT
MAOi = increase Epi, NE, DA, and 5-HT
High Epi-NE, and DA = hypertensive crisis
High 5-HT= serotonin syndrome

Do NOT use together
Use 2 week washout period when switching between drugs with MAOi or serotonergic properties (Except with fluoxetine, wait 5 weeks)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What are some examples of MAOi?

A

Isocarboxazid, phenelzine, tranylcypromine, rasagiline, selegiline, linezolid, methylene blue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What are some examples of drugs/foods that increase Epi, NE, or Dopamine?

A

SNRs, TCAs, bupropion, levodopa, stimulants, including amphetamines used for ADHD (e.g. methylphenidate, lisdexamfetamine, dextramphetamine), tyramine (From foods)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What are some examples of drugs/foods that increase 5-HT?

A

Antidepressants: SSRIs, SNRIs, TCAs, mirtazapine, trazodone
Opioids and analgesics: fentanyl, methadone, tramadol
Others: buspirone, dextromethorphan (when high doses taken as drug of abuse), lithium, St. John’s wort

57
Q

When is it recommended to use a 2-week washout period (exception: ____ with 5 week washout period)?

A

When switching between drugs with MAOi or serotonergic properties
Fluoxetine = 5-week washout

58
Q

What are some tyramine-rich foods?

A

Aged, pickled, fermented, or smoked foods like aged cheeses, air-dried meats, sauerkraut, some wines/beers

59
Q

What is the DDI between CYP2D6 inhibitors and CYP2D6 substrates?

A

Decrease drug substrate metabolism, increase ADRs/toxicity (or decreased efficacy if prodrug)
Avoid using together if possible

60
Q

What are some 2D6 inhibitors?

A

Amiodarone, fluoxetine, paroxetine, fluvoxamine

61
Q

What are some 2D6 substrates?

A

Many, including codeine, meperidine, tramadol, tamoxifen

62
Q

What is the DDI between CYP3A4, P-gp inhibitors and Calcineurin inhibitors (CNIs) or mTOR kinase inhibitors?

A

Decrease drug substrate metabolism, increase ADR/toxicity including increased BP, nephrotoxicty, metabolic syndrome and other adverse effects

CNIs = tacro, cyclosporine
mTOR kinase inhibitors = sirolimus, everolimus

AVOID using together or decrease dose of CNI or mTOR kinase inhibitor based on drug levels

63
Q

What is the DDI between antiepileptic drug (AED) CYP inducers (phenytoin, phenobarbital, primidone, carbamazepine, oxcarbazepine) and other drugs metabolized by CYP enzymes (oral contraceptives, other AEDs, carbamazepine (auto-inducer), others)

A

Increase substrate metabolism = decrease drug levels
Decrease drug effects; with AEDs, loss of seizure control

Monitor drug level; induction takes up to 4 weeks for full effect, may need to increase substrate drug dose

If substrate is lamotrigine, use the starter kit that begins with higher lamotrigine doses

64
Q

What is the DDI between rifampin and CYP and p-gp substrates?

A

Substrate drug conc will greatly decrease
Example: warfarin!

65
Q

What is the DDI between CYP3A4 inducers and opioids that are 3A4 substrates (fentanyl, hydrocodone, oxycodone, methadone)

A

Increased metabolism = decreased opioid conc = less analgesia (pain relief)

66
Q

Patient is a ultrametabolizer of CYP2D6. Which drugs are we concerned about?

A

Codeine, tramadol

2D6 UM, prodrug will convert more rapidly into active drug = increased active drug conc = toxicity/risk and possible fatality

Do NOT use codeine or tramadol in children <12 or <18yo following tonsillectomy and/or adenoidectomy (contraindication)
Do NOT use opioid prodrug that is metabolized by CYP2D6 (tramadol, codeine) in a breast-feeding mother unless it is known she is NOT an UM.

67
Q

Which opioids prodrugs are metabolized by 2D6?

A

Codeine, tramadol

68
Q

What is the DDI between CYP3A4, P-gp inducers and Calcineurin inhibitors (CNIs) or mTOR kinase inhibitors?

A

Increased drug metabolism, decrease transplant drug level, increased risk of transplant rejection
Avoid using together or monitor carefully

69
Q

What is the DDI between smoking and some antipsychotics, antidepressants, hypnotics, anxiolytics, caffeine, theophylline, and warfarin (R-isomer)

A

Smoking induces CYP1A2 (both tobacco and marijuana)
Smokers who quit: When the inducer (cigarettes) is stopped, drug conc of substrates will increase, causing toxicity
Current smoker: CYP1A2 substrate levels decreased

70
Q

Your patient who is on warfarin tells you they recently stopped smoking. What is your concern?

A

Monitor INR. The R-isomer of warfarin (less potent isomer) is metabolized by CYP1A2, but the therapeutic range is narrow and could be affected

71
Q

T/F: Nicotine replacement products (NRT, such as patch/gum) induce CYP enzymes similar to smoking

A

False - they do NOT induce CYP enzymes

72
Q

You are going to initiate warfarin in a pt with social hx (+) smoking. Do you consider starting with higher or lower dose?

A

Higher dose

73
Q

What are some s/sx of serotonin syndrome?

A

Autonomic dysfunction (diaphoresis, N/V, hyperthermia)
Altered mental status (akathisia, anxiety, agitation, delirium)
Neuromuscular excitation (hyperreflexia, tremor, rigidity, tonic-clonic seizures)

74
Q

Which drugs increase risk of serotonergic toxicity?

A

Anti-depressants: SSRIs, SNRIs, TCA, mirtazapine, trazodone
MAOi antidepressants: isocarboxazid, phenelzine, tranylcypromine
Selective MAO-Bi: selegiline, rasagiline
Other MAOi: linezolid, methylene blue
Opioids: fentanyl, meperidine, methadone, tramadol, tapentadol (risk with any opioid used in combo with serotonergic drug)
Triptans: PRN may be safe, more frequent use can increase risk
Natural products: St. John’s wort, L-tryptophan
Others: buspirone, lithium, dextromethorphan (when taken in excess as drug of abuse)

75
Q

Doctor is switching med from fluoxetine to duloxetine. What is the washout period?

A

5 weeks

76
Q

Doctor is switching med from citalopram to escitalopram. What is the washout period?

A

2 weeks

77
Q

Avoid using drugs that increase risk of bleeding in combo with a few exceptions. What are the exceptions?

A

Aspirin (for cardioprotection) and occasional NSAID use for pain, fever, or inflammation
SSRI/SNRI use and occasional NSAID use for pain, fever or inflammation
Dual antiplatelet therapy for select patients (e.g. to prevent cardiac stent thrombosis)
Bridging/overlap treatment (ex. enoxaparin + warfarin)

78
Q

Which drugs increase risk for bleeding?

A

Anticoagulants: warfarin ,dabigatran, apixaban, edoxaban, rivaroxaban, heparin, enoxaparin, dalteparin, fondaparinux, argatroban, bivalirudin
Antiplatelets: salicylates (including aspirin), dipyridamole, clopidogrel, prasugrel, ticagrelor
NSAIDs: ibuprofen, naproxen, diclofenac, indomethacin, others
SSRIs, SNRIs: citalopram, escitalopram, fluoxetine, paroxetine, sertraline, duloxetine, venlafaxine, others
Natural products: 5Gs: garlic, ginger, ginko biloba, ginseng, glucosamine, vitamin E, willow bark, fish oils (high doses)

79
Q

What are the 5G natural products that increase risk of bleeding?

A

Garlic, ginger, ginko biloba, ginseng, glucosamine

80
Q

What drugs increase risk for hyperkalemia?

A

RAAS drugs: ACEi/ARBs, aliskiren, sacubitril/valsartan, spironolactone, eplerenone (highest risk with aldosterone receptor antagonists)
K-sparing diuretics: amiloride, triamterene
Others: Salt substitutes (KCl), CNIs (tacro, cyclosporine), SMX/TMP, canagliflozin, drospirenone-containing oral contraceptives

Do NOT use ACEi with ARBs
Do NOT use sacubitril/valsartan with ACEi or ARBs
Avoid salt substitutes
If risk for hyperkalemia, suggest alternatives to canagliflozin (DM), SMX/TMP (infection) or drospirenone-containing oral contraceptives

81
Q

The risk of QTc prolongation and TdP increases with:

A

higher doses
higher drug levels d/t concurrent enzyme inhibitors
higher drug levels d/t reduced drug clearance, such as renal/liver disease
Multiple QT-prolonging drugs used together
Elderly (>60yo) and patients with CVD, including arrhythmias, HF, MI

82
Q

Generally, limit use of QT-prolonging drugs or select drugs with lower QT risk, especially with arrhythmias, CVD, or CVD risk (exception: ____ is the drug of choice to treat an arrhythmia in pts with HF)

A

Amiodarone

83
Q

Do not exceed citalopram dose ____ or ____ in elderly (>60yo), liver disease, or with enzyme inhibitors that decrease clearance

A

40mg daily
20mg daily with elderly, liver disease, or with enzyme inhibitors

84
Q

Do not exceed escitalopram ____ or ____ in elderly (>60yo)

A

20mg daily
10mg daily with elderly

85
Q

Among SSRIs, ____ is considered safest in pts with CVD

A

Sertraline

86
Q

Do not use ___ for inpatient N/V (it is injection only and has restricted use d/t QT prolongation risk)

A

Droperidol

87
Q

Which anti-infectives increase risk of QT prolongation?

A

Antimalarials (e.g. hydroxychloroquine)
Azole antifungals except isavuconazonium
Lefamulin
Macrolides
FQ

88
Q

Azole antifungals increase risk of QT prolongation EXCEPT ____

A

isavuconazonium

89
Q

Which antidepressants increase risk of QT prolongation?

A

SSRIs: highest risk with citalopram, escitalopram
TCAs
Others: mirtazapine, trazodone, venlafaxine

90
Q

Which SSRIs have highest risk of QT prolongation?

A

Citalopram and escitalopram

91
Q

Which Antipsychotics increase risk of QT prolongation?

A

First-gen (e.g. haloperidol, thioridazone)
Seond-gen: highest risk with ziprasidone

92
Q

Which second-gen antipsychotic has highest risk of QT prolongation?

A

Ziprasidone

93
Q

Which antiemetics increase risk of QT prolongation?

A

5-HT3 receptor antagonists (e.g. ondansetron)
Others: droperidol, metoclopramide, promethazine

94
Q

Which oncology meds increase risk of QT prolongation?

A

Androgen deprivation therapy (e.g. leuprolide)
Tyrosine kinase inhibitors (e.g. nilotinib)
Other: oxaliplatin

95
Q

What are some misc meds that increase risk of QT prolongation?

A

Cilostazol, donepezil, fingolimod, hydroxyzine, loperamide, ranolazine, solifenacin, methadone, tacrolimus

96
Q

What are some drug/drug classes that increase risk of CNS depression?

A

Opioids
Skeletal muscle relaxants
Antiepileptic drugs
Benzodiazepines
Barbiturates
Hypnotics
Antidepressants: mirtazapine, trazodone,
AntiHTN: propranolol, clonidine
Cannabis-related drugs: dronabinol, nabilone
Sedating antihistamines
Cough syrups with antihistamine or opioid
Some NSAIDs

97
Q

Which combo of drugs has highest risk for fatality d/t CNS depression?

A

Opioids + benzodiazepines or other CNS depressants (including alcohol)

98
Q

S/sx of CNS depression

A

somnolence, dizziness, confusion/cognitive impairment, altered consciousness/delirium, gait instability/imbalance/risk of falls/accidents

99
Q

Benzodiazepines are drugs of abuse and often prescribed inappropriately (for anxiety or insomnia). What are some appropriate indications?

A

Status epilepticus, alcohol withdrawal, as an antidote for stimulant overdose, prior to medical procedures, in acute high-anxiety situations for anticipatory emesis with chemo

100
Q

What are some patient counseling points for meds that can cause CNS depression?

A

Do NOT use alcohol
Do not operate car or other vehicles/machiens
Can increase risk of falls, confusion

101
Q

Do ER or IR formulations of opioids have greater risk of fatality when taken with alcohol?

A

ER formulations have higher risk – several become shorter-acting when taken with alcohol

102
Q

Avoid ____ (opioid) if pharmacogenomic profile is unknown (highest risk with CYP2D6 UMs)

A

Codeine

103
Q

Which drugs increase risk of ototoxicity?

A

Aminoglycosides: gentamicin, tobramycin, amikacin, others
Cisplatin
Loop diuretics (esp rapid IV admin): furosemide, bumetanide, ethacrynic acid
Salicylates: aspirin, salsalate, magnesium salicylate, others
Vancomycin

Consider audiology consult at start of treatment for baseline and monitor
Avoid using multiple ototoxic drugs at the same time if possible

104
Q

S/sx otoxicity

A

hearing loss, tinnitus, vertigo

105
Q

Which drugs increase risk of nephrotoxicity?

A

Anti-infectives: aminoglycosides, amphotericin B, polymyxins, vancomycin
Cisplatin
CNIs: cyclosporin, tacrolimus
Loop diuretics: furosemide, torsemide, bumetanide, eythacrynic acid
NSAIDs
Radiographic contrast dye

106
Q

If using cisplatin, use ___ to protect kidneys

A

amifostine (Ethyol)

107
Q

What are anticholinergic symptoms?

A

CNS depression, including sedation, and peripheral anticholinergic side effects of dry mouth, dry eyes, blurry vision, constipation, urinary retention

Highest risk in elderly

108
Q

Which drugs have anticholinergic toxicity risk?

A

Antidepressants/antipsychotics: paroxetine, TCAs, first-gen antipsychotics
Sedating antihistamines: diphenhydramine, brompheniramine, chlorpheniramine, doxylamine, hydroxyzine, cyproheptadine, meclizine
Centrally-acting anticholinergics: beztropine, trihexyphenidyl
Muscle relaxants: baclofen, carisprodol, cyclobenzaprine
Antimuscarinics (for urinary incontinence): oxybutynin, darifenacin, tolterodine
Others: atropine, belladonna, dicyclomine

109
Q

What is the risk of taking PDE-5i (sildenafil, tadalafil, avanafil, vardenafil) with CYP3A4 inhibitors?

A

Decreased PDE-5 inhibitor metabolism = increased side effects (headache, dizziness, flushing = increased risk of falls/injury)

If taking CYP3A4i, start with 50% of usual starting dose of PDE-5i

110
Q

What is the risk of taking PDE-5i with nitrates or alpha-1 blockers (non-selective (e.g. doxazosin, terazosin) or selective (e.g. tamsulosin))?

A

All cause vasodilation
Additive effects can cause to hypotension/orthostasis, dizziness and falls

With nitrates, severe hypotension can cause chest pain and CV events which can be fatal

111
Q

What is your recommendation for PDE-5i and nitrates?

A

Do NOT use together (contraindicated)

112
Q

What is your recommendation for PDE-5i and alpha-1 blockers?

A

Start with low dose when adding a drug for either class (e.g. if taking an alpha-1 blocker, start at half the usual PDE-5i dose)

113
Q

Common CYP3A4 substrate: Analgesics

A

Fentanyl, hydrocodone, methadone, oxycodone
Others: buprenorphine, diclofenac, meloxicam, tramadol

114
Q

Common CYP3A4 substrate: Anticoagulants

A

apixaban, rivaroxaban, R-warfarin

115
Q

Common CYP3A4 substrate: CV drugs

A

Amiodarone, amlodipine, diltizaem, verapamil
Others: bosentan, eplerenone, ivabradine, nifepdipine, quinidine, ranolazine, tolvaptan

116
Q

Common CYP3A4 substrate: Immunosuppressants

A

Cyclosporine, tacrolimus, sirolimus

117
Q

Common CYP3A4 substrate: Statins

A

atorvastatin, lovastatin, simvastatin

118
Q

Common CYP3A4 substrate: HIV drugs

A

Atazanavir, efavirenz, and other NNRTIs, ritonavir, ripranavir

119
Q

Common CYP3A4 substrate: PDE-5i

A

Sildenafil, tadalafil, vardenafil, avanafil

120
Q

Common CYP3A4 substrate: Misc

A

Ethinyl estradiol
Others: alfuzosin, aprepitant, aripiprazole, BZDs, brexpiprazole, buspirone, carbamazepine, citalopram, clarithromycin, colchicine, dapsone, dutasteride, erythromycin, escitalopram, felbamate, haloperidol, ketoconazole, levonorgestrel, mirtazapine, modafinil, ondansetron, progessterone, quetiapine, tamoxifen, trazodone, venlafaxine, zolpidem

121
Q

Common CYP3A4 inducers

A

PS PORCS: Phenytoin, smoking, phenobarbital, oxcarbazepine, rifampin, carbamazepine, St. John’s wort
Others: efavirenz, etravirine, primidone, rifabutin, rifapentine

122
Q

Common CYP3A4 inhibitors: anti-infectives

A

Clarithromycin, erythromycin, azole antifungals
Other: isoniazid

123
Q

Common CYP3A4 inhibitors: CV drugs

A

Amiodarone, diltiazem, verapamil
Others: dronedarone, quinidine, ranolazine

124
Q

Common CYP3A4 inhibitors: HIV drugs

A

Cobicistat, ritonavir, efavirenz and other protease inhibitors

125
Q

Common CYP3A4 inhibitors: misc

A

Grapefruit, cyclosporine
Others: aprepitant, cimetidine, fluvoxamine, haloperidol, nefazodone, sertralien

126
Q

Common CYP1A2 substrates

A

Theophylline, R-warfarin
Others: aldosteron, aprepitant, clozapine, cyclobenzaprine, duloxetine, ethinyl estradiol, fluvoxamine, methadone, mirtazapine, olanzapine, ondansetron, pimozide, propranolol, rasagiline, ropinirole, tizanidine, zolpidem

127
Q

Common CYP1A2 inducers

A

Carbamazepine, phenobarbital, phenytoin, rifampin, smoking, St. John’s wort
Others: ritonavir, primidone

128
Q

Common CYP1A2 inhibitors

A

Ciprofloxacin, fluvoxamine
Others: atazanavir, cimetidine, zileuton

129
Q

Common CYP2C8 substrates

A

Amiodarone, pioglitazone, repaglinide

130
Q

Common CYP2C8 inducers

A

Phenytoin, rifampin

131
Q

Common CYP2C8 inhibitors

A

Amiodarone, atazanavir, clopidogrel, gemfibrozil, ketoconazole, SMX/TMP, ritonavir

132
Q

Common CYP2C9 substrates

A

S-warfarin
Others: alosetron, carvedilol, celecoxib, diazepam, diclofenac, fluvastatin, glyburide, glipizide, glimepiride, meloxicam, nateglinide, phenytoin, ramelteon, tamoxifen, zolpidem

133
Q

Common CYP2C9 inducers

A

Carbamazepine, phenobarbital, phenytoin, rifampin, smoking, St. John’s wort
Others: aprepitant, primidone, rifapentin, ritonavir

134
Q

Common CYP2C9 inhibitors

A

Amiodarone, fluconazole, metronidazole, SMX/TMP
Others: atazanavir, capecitabine, cimetidine, efavirenz, etravirine, gemfibrozil, fluvoxamine, fluorouracil, isonazid, ketoconazole, oritavancin, tamoxifen, valproic acid, voriconazole, zafirlukast

135
Q

Common CYP2C19 substrates

A

Clopidogrel
Others: phenytoin, thioridazine, voriconazole

136
Q

Common CYP2C19 inducers

A

Carbamazepine, phenobarbital, phenytoin, rifampin

137
Q

Common CYP2C19 inhibitors

A

Esomepraozle, omeprazole
Others: cimetidine, efavirenz, etravirine, fluoxetine, fluvoxamine, isoniazid, ketoconazole, modafinil, topiramate, voriconazole

138
Q

Common CYP2D6 substrates

A

Codeine, meperidine, tramadol, tamoxifen
Others:
Analgesics: hydrocodone, methadone, oxycodone
Antipsychotics/antidepressants: aripiprazole, brexipiprazole, doxepin, fluoxetine, haloperidol, mirtazapine, risperidone, thioridazine, trazodone, TCA, venlafaxine
Others: atomoxetine, carvedilol, dextromethorphan, flecainide, methamphetamine, metoprolol, propafenone, propranolol

139
Q

Common CYP2D6 inhibitors

A

Amiodarone, duloxetine, fluoxetine, paroxetine
Others: bupropion, cimetidine, cobicistat, darifenacin, dronedarone, mirabegron, propafenone, quinidine, ritonvair, sertraline

NAPLEX 2024 (74 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions