Quiz 1 Flashcards
(17 cards)
What’s the formula for calculating volume from stock strength?
V = (Prescribed dose × Volume of stock) / Stock dose
Convert 0.4 g to mg.
0.4 g = 400 mg
What is 1% w/v expressed in mg/mL?
10 mg/mL
How many mL would you give for 75 mg from stock 100 mg in 2 mL?
(75×2)/100 = 1.5 mL
Calculate the infusion rate (mL/hr): 500 mL over 4 hours.
500 ÷ 4 = 125 mL/hr
Child weighs 22 kg. Dose is 10 mg/kg/day in two divided doses. What is one dose?
(22×10)/2 = 110 mg
What’s the concentration (mg/mL) of 0.5% lidocaine?
0.5% = 5 mg/mL
What does ‘first-pass metabolism’ refer to?
Metabolism of drug by liver before reaching systemic circulation
What is a drug’s half-life?
Time for plasma concentration to reduce by 50%
Which organ is primarily responsible for drug excretion?
Kidneys
How do ACE inhibitors lower blood pressure?
They inhibit angiotensin I to II conversion, causing vasodilation
What’s a key pharmacokinetic concern in elderly patients?
Reduced renal/hepatic function and polypharmacy risk
What is CYP450 inhibition likely to cause?
Increased drug levels due to reduced metabolism
What’s the mechanism of action of beta-blockers?
Block beta-adrenergic receptors to reduce heart rate and BP
Why might morphine dosing need adjustment in renal failure?
Active metabolites accumulate, increasing risk of toxicity
Which antibiotic class requires dose adjustment in renal impairment?
Penicillins (and most aminoglycosides)
What’s the danger of combining warfarin with NSAIDs?
Increased bleeding risk (both affect clotting pathways)
