NAPLEX Flashcards
specific gravity units
g/ml
SCE or E value units
g NaCl/g drug
mEq to mg or mg to mEq
mg = (mEq)(molecular weight/valence) mEq = (mg)(valence/molecular weight)
BSA equation
square root of: (cm)(kg)/3600
BMI equation
kg/(m^2)
magnesium stearate in compounding
glidant/lubricant
sodium lauryl sulfate in compounding
surfactant to neutralize static charge
adsorbant powders
used to keep powders dry (eutectic mixtures - lower melting point when mixed than either component alone)
magenium oxide, magnesium carbonate, kaolin
emulsifiers
acacia, agar, carbomers, glyceryl monostearate, pectin, PEG, sodium lauryl sulfate, sorbitan lipophilic esters, sorbitan hydrophilic esters
levigating agents
glycerin, mineral oil, PEG, propylene glycol
drugs that cause photosensitivity
carbamazepine, diuretics (thiazide and loop), methotrexate, oral and topical retinoids, quinolones, st. john’s wort, sulfa abx, tacrolimus, tetracyclines, voriconazole
drugs that cause TTP
clopidogrel, ticlopidine
drugs that cause severe skin reactions
allopurinol, lamotrigine, penicillins, phenytoin, piroxicam, sulfamethoxazole
Cl calculations
Cl = Rate of elimination / concentration
Cl = F*dose / AUC
for IV, F = 1
F (bioavailability) calc
F = 100 * (AUC(extravascular)/AUC(IV)) * (Dose(IV)/Dose(extravascular))
k (elimination rate constant) calc
k = Cl/Vd
t1/2 calc
t1/2 = 0.693/k
loading dose calculation
LD = (desired conc)(Vd)/F
CYP inducers
PS-PORCS (big inducers) phenytoin smoking phenobarbital oxcarbazepine rifampin carbamazepine st. john's wort
CYP inhibitors
g pacman (big inhibitors) grapefruit PIs (protease inhibitiors) Azole antifungals C - cyclosporine, cimetidine, cobicistat Macrolides (NOT azithromycin) Amiodarone non-DHP CCBs (dilt and verapamil)
genetic testing strongly recommended prior to starting therapy
abacavir (including Epzicom and Triumeq): HLA-B5701 due to risk of fatal hypersensitivity - must test all patients prior to starting and withhold if positive
Carbamazepine: HLA-B1502 due to SJS or TEN risk - must test all asian patients and withhold if positive
Trastuzumab, adotrastuzumab emtansine: HER2 overexpression is required for use - do not use if negative
Cetuximab: KRAS - drug is not effective in patients with colorectal cancer who have a KRAS mutation - only use if KRAS negative
azathioprine: TPMT - no TPMT activity can lead to increased risk of severe myelosuppression; if TPMT low or absent, start at very low dose or use alt therapy