Naplex Chapter 11 Drug Interactions

Front 1

what is a substrate

Back 1

drugs that are metabolized by the CYP 450 enzyme

Front 2

enzyme inhibitors have what affect on a drug?

what about a pro-drug

Back 2

will inhib metab, thus drug conc increases

a prodrug wont be converted to active form, conc decreases

Front 3

what are p-glycoproteins?

Back 3

efflux transporters found in gut...pump drugs out of blood into the gut

Front 4

name 2 meds that are p-glycoproteins substrates

Back 4

dabigatrin
rivaroxaban

if given with a p-gp inducer/inhibitor these meds will be affected

Front 5

define a strong inhibitor

Back 5

causes a 5 fold increase in drug plasma conc

Front 6

define a moderate inhibitor

Back 6

causes greater than or equal to 2 fold increase, but less than 5 fold

Front 7

common medications that induce...

Back 7

Barbies Smokey car goes real phast
phenobarb
smoking
carbamazepine
grisefluovin
rifampin
phenytoin

Front 8

common inhibitors

Back 8

PACMAN G

Protease inhibitors
azoles (fluconazole, itraconazole)
cimetidine
macrolides (not azithromycin)
amiodarone
non DHP CCB -diltiazem and verapamil
Grapefruit juice

Front 9

medications that interact with amiodarone

Back 9

anything that causes QT prolongation- TCA
negative chronotropics-BB, nonDHP CCB
grapefruit juice

**if starting these, lower there dose by 30-50%: warfarin, digoxin, quinidine
use lower doses of simvastatin, lovastatin, and atorvastatin

Front 10

azole antifungal interactions

Back 10

all are 3A4 inhib.

itra and keto are pH dependent, incre pH, dec absorp.- so avoid H2A, PPI's

Front 11

digoxin interactions

Back 11

renally cleared-so dec dose in renal impairment

hypoaKalemia and hyperCalemia may increase digoxin toxicity

avoid use with non-DHP CCB, azole antifungals,

Front 12

grapefruit interactions

Back 12

statins and CCB - even though not much evidence to support this- Simva, Atorv, Lova

but big interaction with amiodarone-avoid

Front 13

what increases Li levels?

what decreases lvls?

Back 13

100% renally cleared

increases- dec in Na, NSAIDs, ARBs, ACEI's

decreases- incr in Na, caffeine, theophylline

Front 14

what are some other meds to avoid with Li

Back 14

Li increases 5HT, so avoid SSRI's, TCAs, linezolid, triptans

Front 15

MAO-I interactions

Back 15

avoid SSRI, triptans, linezolid, tramadol, PSE

avoid tyramines- aged meats, cheeses, beers, wine

Front 16

NSAID interactions

Back 16

all increase BP, including Celebrex

they increase bleeding, less with Celebrex

avoid with Li use and renal impairment

Front 17

all NSAIDs can cause...

exception?
which causes most?

Back 17

CV toxicity (MI)- ASA is the exception

COX2 selective are pro-thrombotic and have highest risk-Celebrex

Front 18

meds that decrease OC's-for idiots, OC stands for oral contraceptives

Back 18

this really isn't true for abx if you look into the literature

abx- amp, grise, sulfonamides, tetracycline

anticonvulsants- barbituates, carbamazepine, phenytoin
smoking

Front 19

what anti-viral meds should not be used with OCs

Back 19

ritonavir
atazanavir
lopinavir
nelfinavir
nevirapine

Front 20

fluroquinolone interactions

Back 20

anything with multivalent cations- antacids, MVI, Ca, Fe, aluminum, Magnesium- these will decrease FQ

FQ- increase warfarin, sulfonylureas, and QT prolonging drugs (moxiflox prolongs the most)

Front 21

probenacid and NSAIDs have what effect on FQ

Back 21

increase FQ levels

Front 22

rifampin interactions

Back 22

amps stuff, so inducer

decreases warfarin levels, dec INR

Front 23

simvastatin, atorvastatin, and lovastatin (SAL) are metabolized by..

Back 23

3A4, atorvastatin is metabolized less by 3a4 than the others

Front 24

rosuvastatin interactions

Back 24

warfarin, durr
cyclosorin will increase the statin
gemfibrozil- myopathies

Front 25

tetracycline interactions

Back 25

absorption impaired by antacids, divalent cations'
pepto, bile acid resins
separate by 1-2 h before or taken 4 H after tetracycline

Front 26

theophylline interactions

Back 26

3a4 substrate
1st order kinetics, then MM kinetics-be careful

increased by 3a4 inhib, and allopurinol, erythromycin

theo will decrease Li levels

Front 27

warfarin PK interactions

Back 27

its 2C9 substrate

avoid rifampin (large dec in INR) and crap tons of other meds

2c9 inhib-bactrim, amiodarone, abx- all increase INR

Front 28

warfarin pharmacodynamics interactions

Back 28

GI bleeds- use with NSAIDS, aspirin, but INR is within normal range

SSRIs can increase bleeds, without increasing INR

Front 29

dabigatrin interactions

Back 29

avoid rifampin and P-gp inducers

reduce dose if given with ketoconazole

use with P-gp inhibitors ( verapamil, clarithromycin, amiodarone) does not require a dose reduction

Front 30

therapeutic range for carbamazepine

Back 30

4-12 mcg/ml

Front 31

li therapeutic range

Back 31

0.6-1.2 mEq/L

Front 32

phenytoin therapeutic range

Back 32

10-20 mcg/ml

Front 33

theophylline therapeutic range

Back 33

5-15 mcg/ml

Front 34

digoxin therapeutic range

Back 34

0.8-2.0 ng/ml Afib

0.5-0.9 ng/ml CHF

Front 35

valproic acid range

Back 35

50-100 mcg/ml

but in psych world don't see mood stab effects till >125

Front 36

warfarin range

Back 36

2-3, 2.5-3.5 if mechanical mitral valve

Front 37

which med will increase bleeds but not the INR
A)ibuprofen
B)celecoxib ( Celebrex)
C) Both

Back 37

ibuprofen