Appleton Pharmaceutical Calculations Flashcards
(65 cards)
1
Q
- Micro, nano, atto, and mega are prefixes associated with which of the following measuring
systems?
I. Avoirdupois
II. metric
III. Systeme International
(A) I only
(B) III only
(C) I and II only
(D) II and III only
(E) I, II, and III
A
- (D) The metric system is used exclusively in
most nations in the world except the United
States. The prefixes in the metric system are
based on increasing or decreasing magnitudes
of 10, 100, or 1000. Converting from
one set of quantities to another simply requires
the movement of decimal points. For
example, converting 1 kg to g requires moving
the decimal point three places to the
right. The metric system has been expanded
into the Systeme International (SI) measuring
system that encompasses all types of measures.
2
Q
- One hundred (100) micrograms equals (C)
I. 100,000 nanograms
II. 0.1 milligrams
III. 0.001 grams
(A) I only
(B) III only
(C) I and II only
(D) II and III only
(E) I, II, and III
A
- (C) In this example, consider one microgram
as equaling 1000 nanograms; thus, 100 mcg =
100,000 ng.
Since 1 milligram equals 1000 mcg, 100
mcg equals 0.1 mg. If 1 mg equals .001 gram,
0.1 mg or 100 mcg equals 0.0001 g. It may be
clearer if one solves this conversion using dimensional
analysis.
3
Q
- A patient’s serum cholesterol value is reported as 4 mM/L. This concentration expressed
in terms of mg/dL will be (mol. wt. (E) 770mg
cholesterol =386)
(A) 0.154 mg/dL
(B) 1.54 mg/dL
(C) 154 mg/dL
(D) 596 mg/dL
(E) 1540 mg/dL
A
- (C) An increasing number of laboratory test
values and drug doses are being reported in
terms of millimoles (mM). Weight quantities
expressed in molar amounts allow a more realistic
evaluation of the actual number of
drug molecules present, for example, when
comparing salts of a drug. In this problem,
the mM/L concentration is converted by recognizing
that 1 mole of cholesterol weighs
386 g and 4 mmoles equals 0.004 moles.
386 x .004 moles = 1.544 g or 1540 mg/L
1540 mg/L = 154 mg/dL
4
Q
- What is the minimum amount of a potent
drug that may be weighed on a prescription
balance with a sensitivity requirement of 6
mg if at least 98% accuracy is required?
(A) 6mg
(B) 120mg
(C) 180mg
(D) 200mg
(E) 300mg
A
- (E) The minimum weight that can be measured
on any balance can be determined if
the balance’s sensitivity requirement (SR)
and the acceptable percentage of error has
been established. The equation is
SR = (minimum weighable amount) x
(acceptable error)
In this problem, the SR was given as 6 mg
and an accuracy of at least 98% or an error of
not more than 2% is permissible.
(23:35)
100mL
1dL = 4mg/dL
6 mg = (x mg) (2%)
6 mg = (x mg) (0.02)
x=300mg
5
Q
- The upper therapeutic drug concentration for
(C) I and II only vancomycin is considered to be 40 microgram/ml
Express this value in terms of mg/dL.
(A) 0.04mg/dL
(B) 0.44 mg/dL
(C) 4mg/dL
(D) 40 mg/dL
(E) 400 mg/dL
A
- (C) Because 1000 )..I.g = 1 mg and 100 mL = 1
dL, 40 )..I.g/mL = 0.04 mg/mL = 4 mg/dL
Note that when dimensional analysis is
used, all of the units cancel except those appropriate
for the final answer.
6
Q
- Calculate the dose of a drug to be adminis-
(A) I only tered to a patient if the dosing regimen is
(B) III only listed as 2 mg/kg/day. The patient weighs 175 lb.
(A) 78mg
(B) 160mg
(C) 140mg
(D) 350mg
(E) 770mg
A
- (B) Because 1 kg = 2.2 lb
~
175 lb x 2.2 lb x
2mg
kg
160mg
7
Q
- The adult dose of a drug is 250 mg. What
would be the approximate dose for a 6-year old child weighing 60 lb? (Use Young’s Rule.)
(A) 60 mg
(B) 85 mg
(C) 100 mg
(D) 125 mg
(E) 180 mg
A
8
Q
- A package insert lists a drug dose for a
neonate as being 10 mcg/kg/day. The age
range for a neonate is considered to be
(A) birth to 1 month
(B) 1 month to 6 months
(C) 1 month to 1 year
(D) birth to 1 week
(E) 1 year through 5 years
A
9
Q
- The child’s dose of a drug is reported as 1.2
mg/kg body weight. What is the appropriate
dose for a child weighing 60 lb?
(A) 6 mg
(B) 9 mg
(C) 32 mg
(D) 72 mg
(E) 126 mg
A
10
Q
- The infusion rate of theophylline established
for a neonate is 0.08 mg/kg/hr. How many
mg of drug are needed for a 12-hr infusion
bottle if the body weight is 161b?
(A) 0.58 mg
(B) 14 mg
(C) 30 mg
(D) 150 mg
(E) 7mg
A
11
Q
- How many mg of codeine phosphate are being
consumed daily by a patient taking the
following prescription as directed?
Rx
Codeine Phosphate 200mg
Dimetapp Elix q.s 120ml
Sig: :5 i ti.d. p.c. & h.s.
(A) 6.25 mg
(B) 8.25 mg
(C) 19 mg
(D) 25 mg
(E) 33 mg
A
12
Q
- How many mg of codeine base is in each
dose of the cough product used in Question
11? (Mol. wts: codeine = 299; codeine phosphate
=406)
(A) 6 mg
(B) 8 mg
(C) 11 mg
(D) 16 mg
(E) 24 m
A
The relationship between codeine and
codeine phosphate is easily seen when
viewed as a chemical reaction
13
Q
- The directions intended for the patient on a
prescription read 1/1 tbsp ac and hs for 10
days.1/ What is the minimum volume the
pharmacist should dispense?
(A) 160 mL
(B) 200 mL
(C) 400 mL
(D) 600 mL
(E) 800 mL
A
- (0) One tablespoonful (tbsp) delivers 15 mL
of liquid. In this prescription, the patient is
receiving four doses per day for 10 days.
Therefore,
15 mL x 4 doses x 10 days = 600 mL total
14
Q
The USP contains nomograms for estimating
body surface area (BSA) for both children
and adults. Which of the following measure-
ments must be known in order to use this
nomogram?
(A) age and height
(B) age and weight
(C) height and creatinine clearance
(D) height and weight
(E) weight and sex
A
15
Q
The adult dose of a drug is 200 mg. What is
an appropriate dose for an 8-year-old child
whose BSA is calculated to be .6 m2?
Rx
Codeine Phosphate
Dimetapp Elix
Sig: :5 i ti.d. p.c. & h.s.
(A) 6.25 mg
(B) 8.25 mg
200mg
q.s. 120 mLBlood pressure measurements were made for
1 week on five patients with the following
averages:
Patient 1 2 3 4 5
B.P. 140/70 160/84 180/88 190/90 150/70
What is the median systolic pressure?
(A) 80
(B) 83
(C) 84
(D) 160
(E) 164
A
16
Q
- Blood pressure measurements were made for
1 week on five patients with the following
averages:
Patient 1 2 3 4 5
B.P. 140/70 160/84 180/88 190/90 150/70
What is the median systolic pressure?
(A) 80
(B) 83
(C) 84
(D) 160
(E) 164
A
17
Q
- Using the above data, determine the approxi-
mate average diastolic blood pressure value.
(A) 80
(B) 84
(C) 100
(D) 115
(E) 160
A
18
Q
- After 1 month of therapy, all of the patients
listed in Question 16 had a systolic blood
pressure reduction of 10 mm with a standard
deviation (SD) of 5 mm. What percentage of
patients had a reduction between 5 and 15
mm?
(A) 20%
(B) 40%
(C) 50%
(D) 70%
(E) 90%
A
19
Q
Lanoxin Pediatric Elixir contains 0.05 mg of
digoxin per mL. How many micrograms
(mcg) are there in 3 mL of the elixir?
(A) 0.0015
(B) 0.015
(C) 0.15
(D) 1.5
(E) 150
A
20
Q
A pharmacist adds 1 pint of Alcohol USP to 1
L of a mouthwash formula. What is the new
percentage of alcohol present if the origi-
nal mouthwash was labeled as 12% V /V
ethanol?
(A) 30%
(B) 38%
(C) 45%
(D) 57%
(E) 59%
A
21
Q
A prescription calls for the dispensing of a
4% Pilocar solution with the directions of “gtt
i au TID.” How many mg of pilocarpine hy-
drochloride is being used per day? Assume
that the dropper is calibrated to deliver 20
drops to the mL.
(A) 4mg
(B) 6 mg
(C) 12 mg
(D) 24 mg
(E) 60 mg
A
22
Q
The adult intravenous (IV) dose of zidovu-
dine is 2 mg/kg q 4 h six times daily. How
many mg will a 180-lb patient receive daily?
(A) 12 mg
(B) 164 mg
(C) 650 mg
(D) 980 mg
(E) 2160 mg
A
23
Q
A pharmacist dilutes 100 mL of Clorox with
sufficient water to make one quart of solu-
tion. Express the concentration of sodium
hypochlorite in the final dilution as a W/V
ratio. (Commercial Clorox contains 5.25%
W/V sodium hypochlorite.)
(A) 1/10
(B) 1/90
(C) 1/100
(D) 1/180
(E) 1/200
A
24
Q
Cocaine HCl
Tetracaine HCl 2%
Epinephrine HCl
Sodium Chloride injection
4%
O.5mL
1/2000
qs4mL
How many mg of cocaine HCl is in the final
solution?
(A) 400 mg
(B) 4 mg
(C) 20 mg
(D) 8 mg
(E) 160 mg
A
25
How many mL of Adrenalin HCl Solution
(0.1%) may be used to prepare the solution?
(A) 0.002 mL
(B) 0.04 mL
(C) 1 mL
(D) 2mL
(E) 5 mL
26
Parenteral Admixture Order
For: Alex Sanders Room: M 704
(A) .8
(B) 1.5
(C) 8
(D) 10
(E) 50
Cefazolin sodium 400 mg in 100 mL N IS
Infuse over 20 minutes q 6 hr ATC for 3 days
Available in the pharmacy are cefazolin
sodium I-gram vials with reconstitution di-
rections of 2.5 mL. SWFI will give 3.0 mL of
solution.
26. How many mL of the reconstituted solution
are required for each day of therapy?
(A) 1.2 mL
(B) 4.8 mL
(C) 3 mL
(D) 6 mL
(E) 12 mL
27
What infusion rate in mL/min should the
nurse establish for each bottle?
(A) 0.15 mL/min
(B) 0.28 mL/min
(C) 1.1 mL/min
(D) 2 mL/min
(E) 5 mL/min
28
An ICU medical order reads "KCl 40 mEq in
1 liter N/S. Infuse at 0.5 mEq/min." How
many minutes will this bottle last on the pa-
tient?
(A) 20
(B) 80
(C) 500
(D) 1000
(E) 2000
29
The attending physician changes the flow
rate of the above solution (KCl 40 mEq/1 L
N IS) to 2 mEq per hour. What will be the ap-
proximate flow rate in mL/minute?
(A) .8
(B) 1.5
(C) 8
(D) 10
(E) 50
30
An administration set delivers 60 drops to
the mL. How many drops per minute are
needed to obtain 20 units of heparin per
minute if the IV admixture contains 15,000
units per 250 mL of normal saline?
(A) 20
(B) 40
(C) 60
(D) 80
(E) 120
31
Dopamine (Intropin) 200 mg in 500 mL of
normal saline at 5 ).!g/kg/min is ordered for
a 155-lb patient. What is the final concentra-
tion of solution in ().!I mL?
(A) 0.4 ).!g/mL
(B) 2.5 ).!g/mL
(C) 40 ).!g/mL
(D) 400 ).!g/mL
(E) 25 ).!g/mL
32
Referring to Question 31, at what rate
(mL/min) should the solution be infused to
deliver the desired dose of 5 ).!g/kg/min?
(A) 0.35 mL/min
(B) 0.40 mLImin
(C) 0.88 mL/min
(D) 2.0 mL/min
(E) 5.0 mL/min
33
A 250-mL infusion bottle contains 5.86 g of
potassium chloride (KCl). How many mil-
liequivalents (mEq) of KCl are present? (Mol.
wt. KCl =74.6)
(A) 12.7mEq
(B) 20 mEq
(C) 78.5 mEq
(D) 150 mEq
(E) 157 mEq
34
A solution contains 1.5 mEq of calcium per
100 mL. Express the solution's strength of
calcium in terms of mg/L. (The atomic
weight of calcium is 40.)
(A) 30 mg/L
(B) 60 mg/L
(C) 150 mg/L
(D) 300 mg/L
(E) 600 mg/L
35
Calcium chloride (CaCl2 • 2H20) has a for-
mula weight of 147. What weight of the
chemical is needed to obtain 40 mEq of cal-
cium? (Ca =40.1; Cl =35.5; H20 =18)
(A) 0.80 g
(B) 2.22 g
(C) 1.47 g
(D) 2.94 g
(E) 5.88 g
36
A floor nurse requests a 50-mL minibottle to
contain heparin injection 100 units/mL. The
number of mL of heparin injection 10,000
units/mL needed for this order will be
(A) 0.1 mL
(B) 0.5 mL
(C) 1 mL
(D) 2.5 mL
(E) 5 mL
37
The estimated creatinine clearance rate for a
120-lb male patient is 40 mLImin. What
maintenance dose should be administered if
the normal dose was calculated to be 80 mg?
(Assume only renal elimination.)
(A) 60 mg
(B) 20 mg
(C) 120 mg
(D) 160 mg
(E) 240 mg
38
A nursing floor requests one pint of 50% Iso-
propyl alcohol as a rubbing compound. How
many mL of Isopropyl Rubbing Alcohol (70%
VIV) will be needed for compounding this
order?
(A) 170
(B) 342
(C) 480
(D) 672
(E) 684
39
A physician requests 1 lb of bacitracin oint-
ment containing 200 U of bacitracin per
gram. How many grams of bacitracin oint-
ment (500 UI g) must be used to make this
ointment?
(A) 182 g
(B) 200 g
(C) 227 g
(D) 362 g
(E) 400 g
40
Coal tar solution
Salicylic acid
Urea
Triamcinolone acetonide
Alcohol USP
Propylene glycol
5mL
aa5%
0.25 g
20mL
qs 120 mL
What weight of salicylic acid is needed to
prepare 1 pt of the formula listed?
(A) 11.8 g
(B) 12 g
(C) 23.7 g
(D) 24 g
(E) 25 g
41
What percent V IV concentration of alcohol
would be listed on the label?
(A) 8%
(B) 15.8%
(C) 16.7%
(D) 19%
(E) 20%
42
How many mL of triamcinolone acetonide
aqueous injection (40 mg/mL) could be used
to prepare 240 mL of the formula?
(A) 6.3 mL
(B) 12.5 mL
(C) 1.2 mL
(D) 10 mL
(E) 15 mL
43
Propylene glycol was purchased at a cost of
$24.00 per pound. What is the cost of 100 mL
of the liquid? (Specific gravity =1.04)
(A) $2.60
(B) $2.64
(C) $2.75
(D) $5.50
(E) $13.00
44
A pharmacist adds 2 mL of tobramycin injec-
tion (40 mg/mL) to 4 mL of tobramycin oph-
thalmic solution 0.3%. The concentration of
tobramycin in the final mixture will be
___ g/mL.
(A) 0.012
(B) 0.015
(C) 0.03
(D) 0.052
(E) 0.092
45
A hospital clinic requests 2 lb of 2% hydro-
cortisone ointment. How many grams of 5%
hydrocortisone ointment could be diluted
with white petrolatum to prepare this order?
(A) 18.2 g
(B) 27.5 g
(C) 45.4 g
(D) 363 g
(E) 545 g
46
How many mL of glycerin would be needed
to prepare 1 lb of an ointment containing 5%
WIW glycerin? (The density of glycerin is
1.25 g/mL.)
(A) 1.2 mL
(B) 18.2 mL
(C) 22.7mL
(D) 24 mL
(E) 28.4 mL
47
A total parenteral nutrition (TPN) order re-
quires 500 mL of D30W. How many mL of
DsoW should be used if the D30W is not avail-
able?
(A) 125 mL
(B) 300 mL
(C) 375 mL
(D) 400 mL
(E) 200 m
48
How many grams of 1% hydrocortisone
cream must be mixed with 0.5% hydrocorti-
sone cream if one wishes to prepare 60 grams
of an 0.8% W/W preparation?
(A) 6 g
(B) 12 g
(C) 24 g
(D) 36 g
(E) 48 g
49
How many grams of pure hydrocortisone
powder must be mixed with 60 g of 0.5% hy-
drocortisone cream if one wishes to prepare a
2.0% W/W preparation?
(A) 0.90 g
(B) 0.92 g
(C) 0.30 g
(D) 1.2 g
(E) 1.53 g
50
How much sodium chloride is needed to ad-
just the following prescription to isotonicity?
(The E value for sodium thiosulfate is 0.31.)
Rx
Sodium thiosulfate
1.2%
Sodium chloride
qs
Purified water qs 100ml
(A) 0.37 g
(B) 0.45 g
(C) 0.53 g
(D) 0.31 g
(E) 0.90 g
51
How much additional sodium chloride
should be added to the following prescrip-
tion to maintain isotonicity? (Zincfrin is an
isotonic solution)
(A) 0.135 g
(B) 0.4 g
(C) 0.54 g
(D) 0.9 g
(E) None (because Sterile Water for Injection
is already isotonic)
52
How many mg of sodium chloride are
needed to adjust 30 mL of a 4% cocaine HCl
solution to isotonicity. The freezing point de-
pression of a 1% solution of cocaine Hel is
.09 degrees.
(A) 62
(B) 83
(C) 108
(D) 120
(E) 270
53
Estimate the milliosmolarity (mOsm/L) for
normal saline. (Na =23; Cl =35.5)
(A) 150 mOsm/L
(B) 300 mOsm/L
(C) 350 mOsm/L
(D) 400 mOsm/L
(E) 600 mOsm/L
54
How many milliosmoles are present in a so-
lution prepared by dissolving 1000 mg of
sodium chloride in 100 mL DsW? (Na =23; Cl
=35.5; hydrous dextrose =198)
(A) 30
(B) 60
(C) 150
(D) 300
(E) 600
55
How many grams of glacial acetic acid
(99.9% W/W) must be added to 1 gallon of
purified water to prepare an irrigation solu-
tion containing 0.25% W/V acetic acid?
(A) 1.2 g
(B) 9.5 g
(C) 12 g
(D) 20 g
(E) 95 g
56
How much elemental iron is present in every
300 mg of ferrous sulfate (FeS04 • 7HzO)?
[Atomic weights: iron = 55.9; S = 32; 0 = 16;
H =1. Iron has valences of +2 and +3.]
(A) 30 mg
(B) 60 mg
(C) 110 mg
(D) 120 mg
(E) 164 mg
57
The USP states that 1 g of a chemical is solu-
ble in 10 mL of alcohol. What is the percent-
age strength of a saturated solution of this
chemical if alcohol has a sp. gr. of 0.80?
(A) 10.0% W/V
(B) 10.0% W/W
(C) 11.1% W/V
(D) 11.1% W/W
(E) 12.5% W/V
58
What is the decay constant (k) of the ra-
dioisotope 3Zp if its half-life is 14.3 days? (As-
sume that radiopharmaceuticals follow first-
order kinetics.)
(A) 0.048/ day
(B) 0.07/ day
(C) 0.097/ day
(D) O.l/day
(E) 0.15/ day
59
A radiopharmacist prepares a solution of
99mTc (40 mCi/mL) at 6:00 AM. If the solution
is intended for administration at 12:00 noon
at a dose of 20 mCi, how many mL of the
original solution are needed? (The half-life of
the radioisotope is 6 hours.)
(A) 0.5 mL
(B) 1.0 mL
(C) 1.5 mL
(D) 2.0 mL
(E) 5.0 mL
60
60. What concentration of the original 99mTc solu-
tion described in Question 59 will remain 24
hours after its original preparation?
(A) 15 mCi
(B) 10 mCi
(C) 7.5 mCi
(D) 5.0 mCi
(E) 2.5 mCi
61
Rx
Magnesium carbonate
15g
Citric acid (anhydrous)
27.4g
Syrup
60ml
Purified water qs to 350ml
How many grams of magnesium is present in
every 350 mL dose? (Mg = 24.3; Carbonate =
60)
(A) 2.5
(B) 4.32
(C) 6.08
(D) 6.7
(E) 8.6
62
What percent W/V of hydrated citric acid
could be listed in a formula if the anhydrous
citric acid is not available? The hydrated
form of citric acid contains 10% water. (Mole-
cular weight citric acid, anhydrous = 192
g/mole; water =18 g/mole)
(A) 7.0
(B) 7.8
(C) 8.7
(D) 24.7
(E) 30.4
63
A nursing home patient is experiencing diar-
rhea from his enteral nutritional solution,
which has an osmolarity of 520 mOsm/L.
How many mL of purified water are needed
to reduce 500 mL of this solution to an osmo-
larity of 300 mOsm/L?
(A) 290 mL
(B) 310 mL
(C) 360 mL
(D) 500 mL
(E) 870 mL
64
The level of iron impurities in a water sample
is 2 mg per liter. Express this concentration in
terms of ppm.
(A) 0.2 ppm
(B) 2ppm
(C) 20 ppm
(D) 200 ppm
(E) 2000 ppm
65
The concentration of mercury in a water sam-
ple is reported as 5 ppm. Express this concen-
tration as a percentage.
(A) 0.00005%
(B) 0.0005%
(C) 0.005%
(D) 0.05%
(E) 0.5%
