Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

NAPLEX Review UWorld > Ch 3: Drug Interactions > Flashcards

Ch 3: Drug Interactions Flashcards

1
Q

Drugs w/ polyvalent cations or other binding properties

A

Antacids
Multivitamins
Sucralfate
Bild acid resins
Aluminum
Calcium
Iron
Magnesium
Zinc
Phosphate binders

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

Drugs w/ polyvalent cations or other binding properties should be separated from

A

Quinolones
Tetracyclines
Levothyroxine
Oral bisphosphonates

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

What are the major CYP3A4 inhibitors

A

Remember G <3 PACMAN

Grapefruit
<3
Protease inhibitors (PI), especially ritonavir (Norvir)
Azole antifungals (fluconazole, itraconazole, ketoconazole, posaconazole (Noxafil), voriconazole, and isavuconazonium (Cresemba))
Cyclosporine, cimetidine (Tagamet), cobicistat
Macrolides (clarithromycin (Biaxin) and erythromycin, but not azithromycin)
Amiodarone (and dronedarone (Multaq))
Non-DHP CCBs (diltiazem and verapamil)

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

Brand:Generic

Cardizem

A

diltiazem

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

Brand:Generic

Neoral

A

cyclosporine

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

What are the major CYP3A inducers

A

Remember SSR COPP

  • St. John’s Wort
  • Smoking
  • Rifampin (and rifabutin, rifapentine)
  • Carbamazepine (also an auto-inducer)
  • Oxcarbazepine (and eslicarbazepine)
  • Phenytoin
  • Phenobarbital
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Brand:Generic

Dilantin

A

phenytoin

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

P-gp

Substrates

A

Anticoagulants (apixaban, edoxaban, dabigatran, rivaroxaban)

Cardiovascular drugs (digoxin, diltiazem, carvedilol, ranolazine, verapamil)

lmmunosuppressants (cyclosporine, sirolimus, tacrolimus)

HCV drugs (sofosbuvir)

Others (atazanavir, colchicine, dolutegravir, posaconazole, raltegravir, saxagliptin)

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

P-gp

Inducers

A

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

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

P-gp

Inhibitors

A

Anti-infectives (clarithromycin, itraconazole, posaconazole)

Cardiovascular drugs (amiodarone, carvedilol, conivaptan, diltiazem, dronedarone, quinidine, verapamil)

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
11
Q

Enterohepatic recycling ↑ _

A

duration of action

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

Common Cardiovacular Drug Intxn

Amiodarone + Warfarin

A

If using warfarin 1st:
↓ warfarin dose 30-50%

Amiodarone inhibits CYP2C9, which metabolizes warfarin

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

Common Cardiovacular Drug Intxn

Amiodarone + Digoxin

A

If using digoxin 1st:
↓ digoxin dose 50%

Amiodarone inhibits P-gp, digoxin is a P-gp substrate → ↑ risk of bradycardia

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

Common Cardiovacular Drug Intxn: Digoxin + Loop Diuretics

What electrolytes do loops effect?

A

↓ K, Mg, Ca, & Na

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

Common Cardiovacular Drug Intxn: Digoxin + Loop Diuretics

What ↑ the risk of digoxin toxicity?

A

↓ K & Mg

↑ Ca

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

Common Cardiovacular Drug Intxn: Digoxin + Loop Diuretics

Drugs that ↓ HR

A

Amiodarone
Digoxin
BB
Clonidine
Diltiazem
Verapamil

Additive effects when use together. Monitor HR (normal: 60-100 BPM)

Also: dexmedetomide (Precedex)

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

Common Cardiovacular Drug Intxn: Statins + CYP3A4

Which statins ↑ levels of CYP3A4 substrates?

A

Lovastatin
Simvastatin
Atorvastatin

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

Common Cardiovacular Drug Intxn: Statins + CYP3A4

Which statins are contraindicated w/ strong CYP3A4 inhibitors?

A

Lovastatin
Simvastatin

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

Brand:Generic

Altoprev

A

lovastatin

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

Common Cardiovacular Drug Intxn

CYP2C9 inhibitors

A

Azole
Bactrim
Amiodarone
Metronidazole

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

Common Cardiovacular Drug Intxn

CYP2C9 inducers

A

rifampin
St. John’s wort
Phenobarbital
Phenytoin
Primidone

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

Common Cardiovacular Drug Intxn

What do CYP2C9 inhibitors cause warfarin to do?

A

↑ warfarin levels → ↑ INR & bleeding

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

Common Cardiovacular Drug Intxn

What do CYP2C9 inducers cause warfarin to do?

A

↓ warfarin levels → ↓ INR & clotting

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

Inhibitors ↑ substrate Drugs

Which opiods are metabolizedf by CYP3A4?

A

Fentanyl
Hydrocodone
Oxycodone
Methadone

Do NOT use w/ CYP3A4 inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
# Inhibitors ↑ substrate Drugs What drugs have specific instruction not to take w/ grapefruit?
amiodarone simvastatin lovastatin nifedipine tacrolimus
26
# Inhibitors ↑ substrate Drugs Valproate + Lamotrigine Intxn
Valproate ↓ lamotrigine metabolsim → ↑ risk of skin reactions ## Footnote Use starter kit w/ lower doses
27
# Inhibitors ↑ substrate Drugs MAO inhibitors
Isocarboxazid Phenelzine Tranylcypromine Rasagiline Selegiline Linezolid Methylene blue
28
# Inhibitors ↑ substrate Drugs How long is the washout period for MAO inhibitors?
2 weeks
29
# Inhibitors ↑ substrate Drugs Which MAO inhibitor is the exception for the normal washout period?
Fluoxetine: 5 weeks
30
# Inhibitors ↑ substrate Drugs Drugs/Foods that ↑ catecholamines (Epi, NE, DA)
bupropion SNRIs TCAs stimulants levodopa tyramine (from food) ## Footnote Can cause hypertensive crisis
31
# Inhibitors ↑ substrate Drugs Drugs/Foods that ↑ 5-HT
**Antidepressants**: SSRIs, SNRIs, TCAs, mirtazapine, trazodone, **Opioids & analgesics**: fentanyl, methadone, tramadol **Others**: buspirone, lithium, dextromethorphan (high doses), St. John's wort ## Footnote Can cause serotonin syndrome
32
# Brand:Generic Remeron
mirtazapine
33
# Inhibitors ↑ substrate Drugs CYP2D6 inhibitors
Amiodarone, fluoxetine, paroxetine, fluvoxamine
34
# Inhibitors ↑ substrate Drugs CYP2D6 substrates
codeine meperidine tramdol tamoxifen ## Footnote Just some examples
35
# Inhibitors ↑ substrate Drugs Calcineurin inhibitors should be avoided with? | (Tacrolimus, cyclosporine) ## Footnote Also mTOR kinase inhibitors (Sirolimus, everolimus)
CYP3A4 & P-gp inhibitors & inducers ## Footnote Inhibitors: ↓ drug substrate metabolism Inducers: ↑ risk of transplant rejection
36
# Inducers ↓ substrate Drugs Antiepileptic drugs CYP inducers
Phenytoin Phenobarbital Primidone Carbamazepine (self inducer) Oxcarbazepine ## Footnote Some CYP substrates: Oral contraceptives, other AEDs, carbamazepine
37
# Inducers ↓ substrate Drugs Inducer that interacts w/ CYP & P-gp substrates
Rifampin
38
# Inducers ↓ substrate Drugs CYP2D6 UMs
Prodrugs that are CYP2D6 substrates will be more **rapidly converted** → ↑ active drug concentration | Not in inducer ## Footnote Prodrugs: codeine, tramadol
39
# Inducers ↓ substrate Drugs Do not use codeine or tramadol for?
Children **< 12 y/o** or **< 18 y/o following tonsillectomy and/or adenoidectomy** (Contraindicated) OR **Breast-feeding mothers** (unless it is known she is not 2D6 UM)
40
# Inducers ↓ substrate Drugs Smoking Interacts with?
CYP1A2 substrates: Some Antipsychotics Antidepressants Hypnotics Anxiolytics Caffeine **Theophylline** **Wafarin** (**R-isomers**) | Smoking is an CYP1A2 inducer
41
# Additive Risk: Drugs that can cause Serotonergic Toxicity
Antidepressants MAO inhibitors Opioids Triptans Natural Products Others: buspirone, lithium dextromethrophan (high dose)
42
# Additive Risk: Serotonergic Toxicity Antidepressants
SSRIs SNRIs TCAs mirtazapine trazodone
43
# Additive Risk: Serotonergic Toxicity MAO inhibitors
Antidepressants: isocarboxazid, phenelzine, tranylcypromine Selective MAO-B inhibitors: selegiline, rasagiline Otheres: linezolid, methylene blue
44
# Additive Risk: Serotonergic Toxicity Opioids
Fentanyl Meperidine Methadone Tramadol Tapentadol
45
# Additive Risk: Serotonergic Toxicity Natural products
St. John's wort L-tryptophan
46
# Additive Risk: Serotonergic Toxicity Symptoms
Autonomic dysfxn: diaphoresis, N/V, hyperthermia Altered mental status: akathisia, anxiety, **agitation**, delirium Neuromuscular excitation: hyperreflexia, tremor, **rigidity**, tonic-clonic seizures ## Footnote Akathisia: inability to remain still
47
Drugs that ↑ bleeding risk
Anticoagulants Antiplatelets NSAIDs SSRIs SNRIs Natural products: 5Gs, Vit E, willow bark, fish oils (high doses) ## Footnote May or May not effect INR
48
Drugs that can cause hyperkalemia
**Renin-angiotensin-aldosterone system drugs** ACE, ARBs, aliskiren, Entresto, spironolactone, eplerenone (highest risk) **Potassium-sparing diuretis** amiloride, triamterene **Others** Salt substitutes (KCl), calcineurin inhibitors (tacrolimus, cyclosporine), Bactrim, canagliflozin, drospirenone-containing oral contraceptives
49
# Drugs that cause QT prolongation Antiarrhythmics
Class Ia, Ic, III
50
# Drugs that cause QT prolongation Anti-infectives
Antimalarials (hydroxychloroquine) Azole antifungals (except isavuconazonium) Lefamulin Macrolides Quinolones
51
# Drugs that cause QT prolongation Antidepressants
SSRIs (highest w/ citalopram, escitalopram) TCAs mirtazapine trazodone venlafaxine
52
# Drugs that cause QT prolongation Antipsychotics
1st gen: haloperidol, thioridazine 2nd gen: highest risk w/ ziprasidone
53
# Drugs that cause QT prolongation Antiemetics
5-HT3 receptor antagonists (ondansetron) droperidol metoclopramide promethazine
54
# Drugs that cause QT prolongation Oncology Meds
Androgen deprivation therapy (leuprolide) Tyrosine kinase inhibitors (nilotinib) oxaliplatin
55
# Drugs that cause QT prolongation Others
cilostzol denpezil fingolimod hydroxyzine loperamide ranolazine solifenacin methadone tacrolimus
56
# QT prolongation Citalopram dose
40 mg QD 20 mg QD for > 60 y/o
57
# QT prolongation Escitalopram dose
20 mg QD 10 mg QD for > 60 y/o
58
# QT prolongation DOC to treat arrhythmia in pts w/ HF?
amiodarone
59
# QT prolongation Which SSRI is the safest in pts w/ CVD?
sertraline
60
# QT prolongation What antiemetic should not be use for inpatient N/V?
droperidol
61
# CNS Depression What drugs are highest risk for fatality when used in combo?
Opiods + benzodiazepines | Or othe CNS depressants including **alcohol**
62
# CNS Depression Effects
**somnolence** **dizziness** **confusion**/**cognitive impairment** **altered consciousness**/deliriums gaint instability/imbalance/risk of **falls**/accidents
63
What drugs can cause ototoxicity? | Hearing loss, tinnitus, vertigo
**Aminoglycosides**: gentamicin, tobramycin, amikacin **Cisplatin** **Loop diuretics**: furosemide, bumetanide, ethacrynic acid **Salicylates**: aspirin, salsalte, magnesium salicylate **Vancomycin**
64
What drugs can cause nephrotoxicity? | ↑ SCr/BUN
**Anti-infectives**: aminoglycosides, amphotericin B, polymyxins **cisplatin** **Calcineurin inhibitors**: cyclosporine, tacrolimus **Loop diuretics**: furosemide, torsemide, bumetanide, ethacrynic acid **NSAIDs** **Radiographic-contrast dye**
65
What drug w/ cisplatin to protect kidneys?
amifostine (Ethyol)
66
# Anticholinergic Toxicity Antidepressants/antipsychotics
paroxetine TCAs 1st-gen antipsychotics
67
# Anticholinergic Toxicity Sedating antihistamines
diphenhydramine bromphenbiramine chlorpheniramine doxylamine hydroxyzine cyproheptadine meclizine
68
# Anticholinergic Toxicity Centrally-acting anticholinergics
benztropine trihexyphenidyl
69
# Anticholinergic Toxicity Muscle Relaxants
baclofen carisoprodol cyclobenzaprine
70
# Anticholinergic Toxicity Antimuscarinics | For urinary incontinence
oxybutynin darifenacin tolterodine
71
# Anticholinergic Toxicity Others
atropine belladonna dicyclomine
72
Who are at the highest risk of anticholinergic toxicity?
Elderly
73
Side effects of PDE-5 inhibitors & CYP3A4 inhibitors
HA dizziness flushing ↑ risk of falls/injury
74
When starting a PDE-5 inhibitors when a patient is already on a CYP3A4 inhibitor?
1/2 the starting dose of the PDE-5 inhibitor ## Footnote Same for PDE-5 inhibitors w/ alpha-1 blockers
75
PDE-5 inhibitors, _ , & _ causes vasodilation leading to hypotension/orthostasis
nitrates & alpha-1 blockers
76
PDE-5 inhibitors are CI w/?
Nitrates | Causes severe hypotension
77
CYP3A4 substrates
**Analgsics**: fentanyl, hydrocodone, methadone, oxycodone **Anticoagulants**: apixaban, rivaroxaban, R-warfarin **Cardiovascular drugs**: amiodarone, amlodipine, diltiazem, verapamil **Immunosupressants**: cyclosporine, tacrolimus, sirolimus **Statins**: atorvastatin, lovastatin, simvastatin **HIV drugs**: NNRTIs **PDE-5 inhibitors**: avanafil, sildanfil, tadlafil, vardenafil **Others**: ethinyl estradiol
78
CYP1A2 substrates
theophylline R-warfarin
79
CYP1A2 Inducers
Carbamazepine Phenobarbital Phenytoin Rifampin Smoking St. John's wort ## Footnote Also CYP2C9 inducers
80
CYP1A2 Inhibitors
Ciprofloxacin Fluvoxamine
81
CYP2C9 substrate
S-warfarin
82
CYP2C9 inhibitors
amiodarone fluconazole metronidazole Bactrim
83
CYP2C19 substrate
clopidogrel
84
CYP2C19 inhibitors
esomeprazole omeprazole
85
CYP2D6 substrates
Analgesics: codeine, meperidine, tramadol Antipsychotics/Antidepressants Others: tamoxifen
86
CYP2D6 inhibitors
amiodarone duloxetine fluoxetine paroxetine
87
# Brand:Generic Restoril
temazepam
88
# Brand:Generic Aggrenox
Acetylsalicylic acid + Dipyridamole | Blood thinner
89
# Brand:Generic Lotensin
Benazepril
90
# Brand:Generic Lotrel
Amlodipine / Benazepril
91
# Brand:Generic Yasmin
Drospirenone / Ethinyl estradiol ## Footnote Other Brands: Loryna, Vestura, Yasmin, Gianvi, YAZ, Nikki, Zarah, Syeda, and Ocella

NAPLEX Review UWorld (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions