c.They have good precision.
b.They are neither precise nor accurate.
In pharmacy, roman numerals are most likely to be encountered when reading a prescription. Convert the following pharmacy-related examples as directed in the problem. Refer to Appendix A (Parts of a Prescription), and Appendix C (Frequently Used Prescription Abbreviations and Medical Terminology), for more information.
4 fluid ounces
7 ounces
12 ounces
1 ½ teaspoonsful
2 teaspoonsful
2 drops
CCXX tablets
XXXVI capsules
XLIV tablets
iii tsp
ss fl ounces
v mL
Disp #45
Disp 28 tablets
Disp 16 ounces
0.125 mg; units, tenths, hundredths, thousandths
0.5 mL; units, tenths
0.375 g; units, tenths, hundredths, thousandths
0.02389 g; units, tenths, hundredths, thousandths, ten-thousandths, hundred-thousandths
4; units
55; tens, units
675; hundreds, tens, units
12,463; ten thousands, thousands, hundreds, tens, units
11.7
22.4
100.4
49.7
123 mL
1.5 mL
0.5 mL
17.5 mL
Patrick should weigh 2,680 mg of salicylic acid.
Yes, she can draw the amoxicillin suspension up to half-way between the 3.4-mL line and the 3.6-mL line.
12. Dr. Leland calculates that his patient needs a dose of phenobarbital, based on body weight, of 144.58 mg to be given twice a day. Phenobarbital is available in a concentration of 4 mg/mL, so you will need to draw up 36.145 mL for each dose. A 60-mL syringe has 1-mL calibration markings. To what volume should you round to measure as accurately as possible?
The volume should be rounded to 36 mL for accurate measuring.
Promethazine with codeine
Disp: viii fl oz
She sees a 16-fluid ounce bottle that appears to be about half full on the shelf. How many ounces of promethazine with codeine will be left after the prescription is filled?
If she dispenses 8 ounces, as ordered, there will be no promethazine with codeine left after filling the prescription. Half of a 16-ounce bottle is 8 ounces.
Prednisone 1 mg/mL
Disp: 10 day supply
Sig: 3 mg (3 mL) p.o. daily
How much prednisone will Rich dispense in order to provide 10 days’ worth of medication?
If 3 mg (3 mL) are given every day, then 3 mL/day × 10 days = 30 mL total needed.
Vicodin tablets
Disp # XLVIII
Jenny has only one bottle of 100 tablets left and has another prescription for 24 tablets. If she dispenses the Vicodin as ordered here, will she have enough left to fill the second prescription?
XLVII = 48
100 tablets – 48 tablets = 52 tablets
She will have enough to fill both prescriptions.
Morphine Sulfate 2 IV Q 2 h prn pain. If patient becomes overly sedated give Narcan .4 mg SC q 15 min prn excess sedation, up to 3 doses.
Find the sum.
19 + 18 = 37 patients
Find the difference.
100 – 59 = 41 bottles
Find the product.
Find the quotient.
Three hundred 250-mg tablets of vitamin C are to be distributed equally among 150 patients.
300 ÷ 150 = 2 tablets each, no leftovers
1000 ÷ 30 = 33 vials with 10 tablets left over
Simplify each fraction.
Find the product. Write each product in its simplest form.
Find the quotient. Write each quotient in its simplest form.
Find the quotient. Write each quotient in its simplest form.
Find the sum or difference. Write each in the simplest form.
Find the sum or difference. Write each in its simplest form.
Rewrite the mixed number as an improper fraction.
Rewrite the improper fraction as a mixed number.
Find the product.
Find the quotient.
Find the sum.
Rewrite the fraction as a decimal fraction.
Dr. Denton prescribes one tablet of pseudoephedrine 60 mg to be taken twice daily for 1 month. How many tablets should be dispensed?
60 tablets
Dr. Gohan N. Sumi directs patient Nora Maki to take one capsule of Augmentin XR 875 mg 2 times a day for 10 days. How many capsules should be dispensed?
2 capsules/day × 10 days = 20 capsules
Mrs. Johnson is asked to give her daughter Pam three-fourths of a teaspoonful of Bactrim suspension 2 times a day for 14 days. The pharmacist fills the order with a bottle of 20 teaspoonfuls. Is this enough to last for 14 days?
No, she needs 21 teaspoonfuls.
Wanda Hu gets three prescriptions filled every month. Although her insurance company provides prescription coverage, she pays a copay for each prescription. For her birth control tablets she pays $25.00, for her albuterol inhaler she pays $15.00, and for her Advair inhaler she pays $85.00 each month. What is the average copay Wanda pays?
$25.00 + $15.00 + $85.00 = $125.00/3 = $41.67
At the class picnic hot dog eating contest, the senior class representative eats 12 hot dogs in 15 minutes, while the junior class contestant can only manage 8 hot dogs in 15 minutes.
Seniors: 12 hot dogs/15 minutes or 0.8 hot dogs per minute
Juniors: 8 hot dogs/15 minutes or 0.53 hot dogs per minute
Senior
Jon is returning to college and will not come home until fall break in 2 months. He has an inhaler that contains 200 metered doses. His doctor told him to take two inhalations twice daily. Does his inhaler contain enough doses to last until he returns home?
2 inhalations × 2 per day = 4 metered doses per day
4 metered doses × 60 days = 240 metered doses needed
Therefore, no, one inhaler containing 200 metered doses will not last Jon until he returns home for fall break.
Complete the table.
Fraction | Decimal | Percent |
---|---|---|
1/2 | 0.5 | 50% |
3/8 | 0.375 | 37.5% |
3/4 | 0.75 | 75% |
3/5 | 0.60 | 60% |
1/4 | 0.25 | 25% |
2/5 | 0.40 | 40% |
To replenish required stock levels, a pharmacy technician needs to divide 2,000 g of zinc oxide ointment into several differently sized jars. Ten 60-g jars, eleven 90-g jars, and six 30-g jars are filled.
10(60 g) + 11(90 g) + 6(30 g) = 600 g + 990 g + 180 g = 1770 g
20/59 = 0.34 when rounded to two decimal places
For questions 3–7, choose the most appropriate metric unit of length, weight, or volume from the following options: m, cm, L, mL, g, kg, or mg.
100 mL
334 mcg
198 cm
333 mg
955 g
3 kg
1,800 mg
108,000 mcg
0.5 kg
5.04 mg
0.000278 g
4.54 m
267 cm
0.2 L
4,170 mL
300 mL = 0.3 L
0.3 L + 4 L + 1.5 L = 5.8 L
5.8 L × 1,000 mL/L = 5,800 mL
3,012 mg and 3.012 g
444 mcg = 0.444 mg
0.444 mg + 45.5 mg = 45.944 mg
45.944 mg × 1,000 mcg/mg = 45,944 mcg
0.8 L and 800 mL
3,000 mg = 3 g
3 g – 3 g = 0 g
3,000 mg – 3,000 mg = 0 mg
2,500 mg = 2,500,000 mcg
2,500,000 mcg – 1,000 mcg = 2,499,000 mcg
2,499,000 mcg × 1 mg/1,000 mcg = 2,499 mg
75 mL = 0.075 L
1 L – 0.075 L = 0.925 L
0.925 L × 1,000 mL/L = 925 mL
1,330,000 mg
0.275 L
1 m
0.00512 g
0.125 mg × 1,000 mcg/mg = 125 mcg. This is the correct dose.
0.75 mg
800 mcg
2.326 L
0.5 kg
2,840 mg
8.1 mg (rounded)
15 mL = 1/2 fl oz (30 mL/oz)
15 mL × 1 tsp/5 mL = 3 tsp
16 oz/pt × 30 mL/oz = 480 mL
480 mL × 1 L/1,000 mL = 0.48 L
1 qt/2 pt × 1/2 pt = 1/4 qt
1/4 qt × 960 mL/qt × 1 L/1,000 mL = 0.24 L
0.25 L × 1,000 mL/L = 250 mL
250 mL × 1 fl oz/30 mL = 8.3 fl oz
14.2 g
170.3 g
42.6 g
Solution: Convert each quantity to mL and compare.
1,000 mL
6
30 mL
3
15 mL
2
1 mL
1
480 mL
4
960 mL
5
8 mL
120 mL
1,920 mL
360 mL
30 mL
7.5 mL
1.3 qt
1.25 L × 1,000 mL/L × 1 qt/960 mL = 1.3 qt
240 mL
30 mL/fl oz × 8 fl oz = 240 mL
4 tsp
20 mL × 1 tsp/5 mL = 4 tsp
6 fl oz
180 mL × 1 fl oz/30 mL = 6 fl oz
2
1
3
4
5
6
0.4 lb × 454 g/lb × 1,000 mg/g = 181,600 mg
1.1 kg × 1,000 g/kg × 1,000 mg/g = 1,100,000 mg
8 oz × 28.4 g/oz × 1,000 mg/g = 227,200 mg
20 gr × 1 g/15.4 gr × 1,000 mg/g = 1,299 mg
4.7 kg
9.5 kg
48 lb
170.7 lb
61.4 kg
120.2 kg
Theresa should pull an 8-fl-oz bottle from the shelf. Given that 1 fl oz = 30 mL (approximately), an 8-fl-oz bottle would be required to prepare a 240-mL suspension.
145 lb × 1 kg/2.2 lb = 66 kg
130 mg
3.25 mL
The person who did the calculation multiplied pounds × 2.2 lb/kg instead of dividing. Mrs. Jones actually weighs 51.4 kg.
273 mg, likely rounded to 275 mg
45 lb × 1 kg/2.2 lb = 20 kg (rounded) × 2 mg/kg = 40 mg
40 mg × 1 mL/10 mg = 4 mL
20 mg/kg × 30 kg = 600 mg
15 mg/kg × 30 kg = 450 mg
1/150 gr = 0.007 gr
65 mg/1 gr = x/0.007 gr
x = 0.45 mg
The 0.4-mg tablet is the correct choice.
15 mL
5 mL
5.2 pt
16.7 fl oz
(2 × 4 fl oz) + 6 fl oz = 14 fl oz
240 mL + 180 mL + 120 mL = 540 mL
540 mL × 1 oz/30 mL = 18 fl oz
14 fl oz + 18 fl oz = 32 fl oz dispensed
32 fl oz × 30 mL/fl oz = 960 mL
0.6 mg/tablet × 25 tablets = 15 mg nitroglycerin in one bottle
15 mg × 1 gr/65 mg = 0.23 gr per bottle of 0.6 mg nitroglycerin
1/4 gr × 65 mg/gr = 16.25 mg
1/2 gr × 65 mg/gr = 32.5 mg
1 gr = 65 mg
1 1/2 tsp = 7.5 mL
7.5 mL × 4 times/day = 30 mL/day
30 mL/day × 8 days = 240 mL needed for 8 days
240 mL = 8 fl oz
2 tsp = 10 mL needed per day
10 mL × 10 days = 100 mL must be dispensed
2300 is 11:00 p.m. Therefore, medication should be given at 11:00 p.m., 3:00 a.m., 7:00 a.m., 11:00 a.m., 3:00 p.m., and 7:00 p.m.
2345 and 0015, respectively
1600 − 1200 = 4:00 p.m.
The first dose was given at the correct time; the second should have been given at 5:00 p.m. and the third at 9:00 p.m.
2100 is 9:00 p.m. (first dose). Subsequent doses should be given at 0300 (3:00 a.m.), 0900 (9:00 a.m.), 1500 (3:00 p.m.), and at 2100 (9:00 p.m.).
37°C
°F = (1.8)°C + 32 = 37.6(1.8) + 32 = 99.7°F
Between 704°C and 1,204°C
°F = −40(1.8) + 32 = −40°F
−123.2°F
68°F
Between 68°F and 77°F
°C = (59 – 32)/1.8 = (27)/1.8 = 15°C
(86 – 32)/1.8 = (54)/1.8 = 30°C
Between 15°C and 30°C
−20°C and −10°C
°F = 1.8(–32) + 32 = −26°F
°F = 1.8(–26) + 32 = −15°F
Between −26°F and −15°F when rounded
Yes, that would be a temperature of −23°C.
°C = (–50) – 32/1.8 = −46°C
49°C
°F = 1.8(2) + 32 = 36°F
°F = 1.8(8) + 32 = 46°F
Refrigerator temperatures range from 36°F to 46°F; therefore, the medication should be refrigerated.
−50°C and −15°C
Patient name and address
Name, formulation, and strength of the medication
Quantity of the medication to dispense
Directions to the patient (route of administration, frequency of administration)
Date written (time in institutional setting, if applicable)
Prescriber name and address
Prescriber signature
Prescriber license classification
a sufficient quantity
up to
of each
by mouth
IV push
intramuscular
topical
Take one (1) tablet by mouth two times a day.
Take two (2) capsules by mouth every 6 hours for 7 days.
sig: 20 units sc qAM
Inject 20 units (0.2 mL) under the skin every morning.
sig: gtts iii a.s. t.i.d. × 5 d. Place cotton in L canal
Instill three (3) drops into the left ear three times a day for 5 days. Place cotton in the left ear canal after the drops.
1.1 + 3 + 5 = 9 2. 2 + 4 + 6 = 12
3. 2 × 12 = 24 4. 24 + 9 = 33
Could be valid
1. 2 + 5 + 3 = 10 2. 7 + 4 + 8 = 19
3. 2 × 19 = 38 4. 38 + 10 = 48
Could be valid
1. 5 + 0 + 3 = 8 2. 7 + 4 + 8 = 19
3. 19 × 2 = 38 4. 38 + 8 = 46
Could be valid
Each dose is 15 mL. 6 doses × 15 mL = 90 mL/day × 5 days = 450 mL
cap
susp.
p.c.
BID
u.d.
NKA
At bedtime.
How much insulin will the patient use in 1 week?
He or she will use 105 units or 1.05 mL.
0.15 mL/day × 28 days = 4.2 mL used
10 mL − 4.2 mL = 5.8 mL remaining
The following information is missing from this prescription: the volume to be dispensed, the route of administration (it is safe to assume that it is to be given by mouth because it is ordered as a teaspoonful), and the duration of therapy.
Instill two (2) drops in the left eye four times a day while awake.
Take one (1) tablespoonful (15 mL) by mouth every 4 hours as needed for cough or congestion.
Place one (1) tablet under the tongue as needed for chest pain. May repeat every five (5) minutes for a total of 3 doses if chest pain persists.
Take two (2) capsules by mouth twice a day for blood pressure.
ounce
before meals and at bedtime
every eight (8) hours
as needed
both ears
a sufficient quantity
Rx: Azithromycin 250-mg tablets
Disp: 5 days’ supply
Sig: tabs ii now, then i tab daily
2 (now) + (1 tab/day × 4 d) = 6 tablets
Every 12 hours = 2 doses per day
2 doses/day × 7 days/week × 6 weeks = 84 doses
Amoxicillin susp. 400 mg/5 mL
320 mg (4 mL) Q8H × 7 days
Amoxicillin 400 mg/5 mL for suspension is available in 50 mL, 75 mL, and 100 mL bottles. Which size will be dispensed?
4 mL/dose × 3 doses/day = 12 mL/day
12 mL/day × 7 days = 84 mL; therefore, the 100-mL bottle is necessary
Patient A: Hydromorphone 1 mg Q4H prn moderate pain
Patient B: Hydromorphone 1 mg Q2H prn moderate to severe pain
Patient C: Hydromorphone 0.5 mg Q3H for pain
Assume that each patient will take the maximum dose allowed. There are 12 vials available in the unit. Partial vials cannot be saved for another dose.
26; Patient A needs 6 vials, Patient B needs 12 vials and Patient C needs 8 vials to last for one 24 hour period.
26 − 12 = 14
24 hr/day × 1 dose/2 hr = 12 doses/day
3 doses/day
24 hr/day × 1 dose/8 hr = 3 doses/day
24 hr/day × 1 dose/4 hr = 6 doses/day
2 doses/day
24 hr/day × 1 dose/6 hr = 4 doses/day
one BID for acne
disp: 1 month’s supply
2 doses/day × 30 days = 60 capsules
q3h prn diarrhea, max 6/days
disp: 1 week’s supply
6 tablets/day × 7 days = 42 tablets
Week 1: 86 tablets; Week 3: 93 tablets
Week 2: 120 tablets; Week 4: 112 tablets
103 (rounded)
125 − 7 = 118 tablets
Sig: Inhale two (2) puffs by mouth twice a day
Disp: 12 g (120 metered dose actuations)
Total quantity dispensed = 120 puffs (metered dose acutations)
2 puffs/dose × 2 doses/day (BID) = 4 puffs per day
Days’ supply = 120 puffs/4 puffs per day = 30 days’ supply
Sig: Take one (1) tablet by mouth twice a day
Disp: 180 tabs
Total quantity dispensed = 180 tabs
1 tab/dose × 2 doses/day (BID) = 2 tabs per day
Days’ supply = 180 tabs/2 tabs per day = 90 days’ supply
Sig: Inject 0.3 mL (30 units total) under the skin before meals
Disp: 2 10-mL vials
Total quantity dispensed = 20 mL (2 10-mL vials)
0.3 mL/dose × 3 doses/day (ac) = 0.9 mL per day
Days’ supply = 20 mL/0.9 mL per day = 22 days’ supply (rounded)
Total quantity dispensed = 150 mL
5 mL/dose (1 tsp) × 2 doses per day = 10 mL per day
Days’ supply = 150 mL/10 mL per day = 15 days’ supply
x = 200
x = 12
x = 460
30x + 15 = 615
30x + 15 – 15 = 615 – 15
30x = 600
x = 20
Let x equal the number of individual prescriptions that can be dispensed.
Let x equal the number of 250-mg tablets needed to fill the 10-day prescription.
Let x equal the number of grams of diazepam the patient will take in 30 days.
Let x equal the number of milligrams of furosemide the patient will take in 7 days.
Let x equal the number of milligrams of metformin the patient will take in 30 days.
Let x equal the number of tablets needed to fill the prescription. Estimate 45 to 50 tablets (3 tablets twice a day = 6 per day for 7 days plus extras).
Let x equal the number of milligrams of tetracycline taken over 30 days. Estimate 50,000 mg.
Let x equal the number of 25-mg sertraline tablets dispensed. By estimating two tablets for 7 days, three tablets for 7 days, and four tablets for 16 days, approximately 100 sertraline 25-mg tablets are needed.
Let x equal the number of bottles that remain after two-thirds are removed. Estimate 50.
Let x equal the number of milliliters of active ingredient. Estimate 60 mL (25% of 250 mL).
Let y equal the number of milliliters of flavoring syrup. Estimate 25 mL (10% of 250 mL).
Let z equal the number of milliliters of water. Estimate 250 mL – 60 mL (active ingredient) – 25 mL (flavoring syrup) = 165 mL of water.
240 tablets
8 capsules each containing 0.0325 g
12 capsules each containing 0.015 g
18 capsules each containing 0.0008 g
Do you have enough active ingredient to prepare all the capsules? If so, how many grams of active ingredient are left after you prepare all the capsules?
Let x equal the number of grams of active ingredient that are left.
x = 2 – 8(0.0325) – 12(0.015) – 18(0.0008)
x = 1.5456 g
Yes, you have enough active ingredient to prepare all the capsules. There will be approximately 1.5 grams of active ingredient remaining.
0.45 g diphenhydramine hydrochloride
28 tablets
1,050 mg
Let x equal the number of acetaminophen tablets needed for 5 days.
x = (1,000 mg × 4 times daily × 5 days of treatment)/500-mg tablets
The patient must buy a bottle of acetaminophen 500 mg that contains a minimum of 40 tablets.
Let x equal the number of milligrams of warfarin taken in 3 months.
x = (5 mg/day)(90 days)
x = 450 mg
The patient takes 450 mg of warfarin in 3 months.
6 c potatoes/8 servings
475 miles/10.5 gal
$6.99/12 oz
900 cal/1 double cheeseburger
1:10,000
3:100
1:3
3/4
1/10
9/1,000
2/3
Tetracycline 250 mg/cap
Phenobarbital 20 mg/5 mL
Amikacin 250 mg/mL
Enalapril 10 mg/tab
Source: Reprinted with permission of Hospira, Inc.
20 mg/mL
Source: Reprinted with permission of Pfizer, Inc.
40 mg/mL
units
40 mg/4 mL = 10 mg/x
x = 1 mL
1 g/10 mL = 0.5 g/x
x = 5 mL
1:1,000 means 1 g/1,000 mL and 1:10,000 means 1 g/10,000 mL, so 1:1,000 contains more epinephrine per milliliter.
Because 1 g = 1,000 mg, 1,000 mg/10,000 mL = x/10 mL
x = 1 mg
1.4 mL
400 mg/5 mL = 300 mg/x
x = 3.75 mL
24 hr/day × 1 dose/6 hr = 4 doses/day
3.75 mL/dose × 4 doses/day = 15 mL/day or 150 mL in 10 days
Dispense the 200-mL bottle
2.25 g sodium chloride in 250 mL normal saline
125 mg/5 mL = 250 mg/x
x = 10 mL
10 mL/dose × 2 doses/day = 20 mL/day
240 mL/bottle × 1 day/20 mL = 12 days/bottle
Read 1 is to 10,000 as 5 is to x. Equation may be rewritten 1/10,000 = 5/x, or solved as follows: 1(x) = 5 (10,000)
x = 50,000
x (10 mL) = 1 g (350 mL)
x = 35 g
x (500 mcg) = 750 mcg (2 mL)
x = 3 mL
3 (162) = 18 (x)
x = 27
x (100 units) = 15 units (1 mL)
x = 0.15 mL
f. 100 mg/x = 5 g/10 mL
Given that 5 g = 5,000 mg, x (5,000 mg) = 10 mL (100 mg)
x = 0.2 mL
292.5 g/130,000 tabs = 2.25 mg/tab
1 tablet weighs 37.5 mg
0.5 mg active ingredients/37 mg filler, or 1:74
2,030 cal/8 pieces = x/3 pieces
x = 761.25 cal
1,040 cals/260 g carbs = 4 cal/g carbohydrate
2,030 total cal – 1,040 cal (from carbs) = 990 cal from fat
990 cal/110 g fat = 9 cal/g fat
Erythromycin 2 g
Hydroxypropyl cellulose 2 g
Ethyl alcohol 70% qs 100 mL
The pharmacy technician must prepare a pint of the gel.
2 g/100 mL = x/480 mL
x = 9.6 g erythromycin
9.6 g hydroxypropyl cellulose
8 fl oz × 30 mL/fl oz = 240 mL
200 mg/5 mL = x/240 mL
x = 200 mg (48) = 9,600 mg or 9.6 g guaifenesin
pseudoephedrine 40 mg/5 mL = x/240 mL
x = 40 mg (48) = 1,920 mg or 1.92 g pseudoephedrine
10 mL/dose × 3 doses/day = 30 mL/day
30 mL/day × 1 bottle/240 mL = 1 bottle/8 days
250 mg/10 mL = 125 mg/x mL
x (250 mg) = 125 mg (10 mL)
x = 5 mL/8 hr
5 mL × 3 doses per day (q 8 hr) = 15 mL needed per day
250 mg/10 mL = x mg/15 mL
x (10 mL) = 15 mL (250 mg)
x = 375 mg/day
15 mL/day × 10 days = 150 mL of Augmentin suspension are needed
1 fl oz/30 mL = x fl oz/150 mL
x (30 mL) = 150 mL (1 fl oz)
x = 5 fl oz
Therefore, the pharmacy technician would need to obtain an empty medication bottle from the shelf that would contain 5 fl oz of medication. In a community pharmacy practice, this most likely would mean that the pharmacy technician would obtain an 8-fl-oz bottle from the shelf to prepare the medication (assuming only 4-fl-oz and 8-fl-oz bottles are available within this range).
2 mg/mL = 40 mg/x mL
x (2 mg) = 40 mg (1 mL)
x = 20 mL/syringe
20 mL/syringe × 100 syringes = 2,000 mL
2 mg/mL = x mg/2,000 mL
x (1 mL) = 2,000 mL (2 mg)
x = 4,000 mg/bulk bottle
Convert the 4,000 mg to the equivalent amount of grams. For this example, use another proportion equation to solve the conversion.
4,000 mg/x g = 1,000 mg/g
x (1,000 mg) = 4,000 mg (1 g)
x = 4 g/bulk bottle
You will provide 37.5-mg tabs because they require the least amount of tablet splitting, thereby being safest and most convenient for the patient.
1.5 of the 37.5 mg tablets = 56.25 mg
12.3 kg
12.3 kg (0.15 mg/kg) = 1.8 mg
0.92 mL
19 lb × 1 kg/2.2 lb = 8.64 kg
8.64 kg × 80 mg/kg = 691 mg
1 g/50 mL = 0.691 g/x
x = 35 mL
This volume would be prepared across two divided doses (ie, two 17.5 mL doses).
10 mL
5 mL every day for 4 days
30 mL
40 mg/1 mL = 60 mg/x
x = 1.5 mL
40 mg/1 mL = 100 mg/x
x = 2.5 mL
40 mg/mL × 30 mL/vial = 1,200 mg/vial
Amount remaining = 1,200 mg − amount used
Amount used = 60 mg (2) + 100 mg + 80 mg (3) = 460 mg used
1,200 mg − 460 mg = 740 mg remaining
4.5 tablets needed, so you must dispense 5 tablets
Take 1.5 tablets (150 mg) by mouth daily for 3 days
16 lb × 1 kg/2.2 lb = 7.3 kg
7.3 kg × 10 mg/kg = 73 mg
100 mg/5 mL = 73 mg/x
x = 3.7 mL (rounded)
97.7 kg
6.4 kg
80 kg
35.5 kg
60.9 lb
248.6 lb
121 lb
71.1 lb
0.27 mL
0.58 mL
0.07 mL
1.93 m2
2.52 m2
2.39 m2
1.09 m2
0.65 m2
10,000 units/1 mL = 22,500 units/x
x = 2.25 mL
8 days
1.51 m2 × 4 mg/m2 = 6.04 mg or 6 mg (rounded) vinblastine/wk
At 8 inhalations/week, one canister will last 25 weeks. She only needs one canister.
125 mcg = 0.125 mg, 100 mcg = 0.1 mg
Total mg/day = 0.125 mg + 0.175 mg + 0.1 mg + 0.075 mg = 0.475 mg
8 days
7 bags with 4 mL of penicillin G left over
1.56 m2 × 1.4 mg/m2 = 2.2 mg
Blood sugar of 270 mg/dL − goal blood sugar of 110 mg/dL = excess blood sugar of 160 mg/dL
160 points sugar excess × 1 unit/40 points excess = 4 extra units
Total Humalog dose = 5 usual units + 4 units for excess = 9 units
A physician has ordered Trileptal suspension 300 mg/5 mL for a boy with a seizure disorder. The child is to receive 10 mg/kg/day initially, in two divided doses, with the dose to be increased gradually over time. The child weighs 66 lb.
66 lb × 1 lb/2.2 kg = 30 kg
30 kg × 10 mg/kg/day = 300 mg/day divided into 2 doses = 150 mg/dose
15 mg/kg/day, 225 mg/dose
300 mg/5 mL = 450 mg/x
x = 7.5 mL
Rx: Trileptal suspension 300 mg/5 mL, 1-month supply
Sig: 450 mg BID
What volume of the drug should the pharmacy supply to last 1 month?
15 mL/day × 30 days = 450 mL
24.1 lb × 1 kg/2.2 lb = 10.9 kg
10.9 kg × 50 mg/kg/day = 545 mg/day, 275 mg/dose
a. 0.15
15 parts per 100 or 15%
b. 22/100
22%
c. 0.63
63%
d. 3/4
0.75 or 75%
e. 1.1
110%
f. 17/24
0.71 or 71% (rounded)
a. 0.75
75%
b. 33/100
33%
c. 0.81
81%
d. 5/8
62.5%
e. 1.2
120%
f. 3/25
12%
a. mg/g = w/w
b. g/mL = w/v
Source: Reprinted with permission from Hospira, Inc., Lake Forest, IL.
a. 5% (w/v)
5 g/100 mL
b. 24% (w/w)
24 g/100 g
c. 0.1% (v/v)
0.1 mL/100 mL
0.9 g/100 mL
0.75 mL/100 mL
10 g/100 g
48 g
120 mL of sterile water plus 120 mL of 6% hydrogen peroxide will make 240 mL of 3% hydrogen peroxide.
a. How many milligrams of timolol are in a 10-mL bottle of 0.25% solution?
0.25 g/100 mL × 10 mL/bottle = 0.025 g/bottle = 25 mg/bottle
b. How many milligrams of timolol are in a 15-mL bottle of 0.5% solution?
0.5 g/100 mL × 15 mL/bottle = 0.075 g/bottle = 75 mg/bottle
60 mg/mL = 6,000 mg/100 mL = 6 g/100 mL = 6%
b. How much of the cream base is needed for this product?
454 g total − 13.62 g hydrocortisone = 440.38 g base
c. Is this a w/w or w/v problem?
w/w
a. How many grams of dextrose will the patient receive in 1 hour?
6.25 g/hr
b. How many grams of dextrose will the patient receive in 1 day?
150 g/day
1 mg/mL = 100 mg/100 mL or 0.1 g/100 mL = 0.1%
2.25 g/250 mL = 0.9%
a. What is the final concentration of dextrose in the 1-L bag?
Final solution contains 125 g/1,000 mL or 12.5% dextrose.
Final solution contains 35 g/1,000 mL or 3.5% amino acid.
Use the alligation alternate method to determine 10 parts of 5% dextrose and 5 parts of 20% dextrose/500 mL 10% dextrose.
333.3 mL of 5% dextrose and 166.7 mL of 20% dextrose = 500 mL of 10% dextrose
y = 1.54 mL of 13% phenobarbital solution
6/8 or 3/4
Ibuprofen 60 × 200 mg = 12,000 mg = 12 g
Pseudoephedrine 60 × 30 mg = 1,800 mg = 1.8 g
For patients with stomatitis (mouth sores or inflammation), the hospital where you work prepares a mouthwash called “magic mouthwash,” which contains the following ingredients:
Hydrocortisone 100 mg/2 mL: 2 mL
Nystatin suspension: 30 mL
Viscous lidocaine 2%: 50 mL
Diphenhydramine elixir 12.5 mg/5 mL qs ad: 240 mL
Hydrocortisone 100 mg/2 mL = 2 mL × 0.75 = 1.5 mL
Nystatin suspension = 30 mL × 0.75 = 22.5 mL
Viscous lidocaine 2% = 50 mL × 0.75 = 37.5 mL
Diphenhydramine elixir = 118.5 mL
MWQ = 250 mg
250 mg
250 mg
0.5 mg/mL = x/10 mL
x = 5 mg
10 mg/1 mL = 5 mg/x
x = 0.5 mL of the morphine sulfate 10 mg/mL concentration
10 mL total − 0.5 mL morphine = 9.5 mL of normal saline
0.5 mg/mL = 0.25 mg/x
x = 0.5 mL
(5 mg x 100)/4 = 125 mg
10 mg/20 mL = 125 mg/x
x = 250 mL
120 tablets/bottle × 650 mg/tablet × 1,000 bottles = 78,000,000 mg = 78,000 g = 78 kg
120 tablets/bottle × 500 mg/tablet × 1,000 bottles = 60,000,000 mg = 60,000 g = 60 kg
% error = ( | 260 mg − 264 mg | / 264 mg ) × 100 = ( 4 / 264 ) × 100
% error = 1.5%
The accuracy of the syringe or the accuracy of the graduated cylinder could account for the shortage. A graduated cylinder is generally considered less accurate than a syringe.
% error = ( | 42 mL − 45 mL | / 42 mL ) × 100 = ( 3 / 42 ) × 100
% error = 7.1%
50 mL – 45 mL = 5 mL displaced by powder
1 g/5 mL = 2 g/x
x = 10 mL
14 mL
4 mL/vial
0.4 mL
5 g
40 mg/1 mL
6.25 mL
15.4 mEq/100 mL NS
48 mL
4.2% = 4,200 mg / 100 mL × 1 mEq/84 mg × 10 mL/syringe = 5 mEq/syringe
5 mEq/10 mL = 0.5 mEq/1 mL
15 minutes (0.25 hour)
30 minutes (0.5 hour)
45 minutes (0.75 hour)
1 hour
3,000 mL/24 hr = x/1 hr
x = 125 mL, or 125 mL/hr rate
Calculate the time from 1700 to midnight and from midnight to 0900.
(2400 − 1700) + (0900 − 0000) = 7 + 9 = 16 hours
125 mL/hr × 16 hours = 2,000 mL
2,000 mL × 1 bag/1,000 mL = two 1-liter bags
1,200 gtt/hr × 1 hr/60 min = 20 gtt/min
4 g in 100 mL
First 100 mL will last 30 minutes + remaining 400 mL will last 8 hours
Total time 8.5 hours
10 hours
1,600 mcg/mL × 2 = 3,200 mcg/mL = 3.2 mg dopamine/mL × 100 mL bag = 320 mg × 1 mL/40 mg = 8 mL
400 mcg/min × 60 min/hr = 24,000 mcg/hr = 24 mg/hr
320 mg/bag × 1 hr/24 mg = 13.3 hours for one bag
First 4 hours, 1,000 mL, then 150 mL/hr × 2 hours, for a total of 1,300 mL
100 mL/hr × 24 hr/day = 2,400 mL. However, the IV is turned off for 2 hours each day, so 2,400 mL – 200 mL = 2,200 mL/day.
1 unit/mL, so 8 units/hr = 8 mL/hr; 8 × 4 hours = 32 mL; 6 mL/hr × 3 hours = 18 mL; 5 mL/hr × 7 hours = 35 mL
Total used = 85 mL with 15 mL remaining
125 mL/hr × 24 hours = 3,000 mL = 3 L
Therefore, three 1,000-mL 0.9% NaCl bags are needed for a 24-hour period.
20 mL/hr
0700 hours
1,000 mL – 500 mL (used in first 2 hours) = 500 mL remaining
500 mL/4 hr (remaining in 6 hours) = 125 mL/hr
Joe’s Pharmacy buys 30 Lipitor 80-mg tablets for $175.00 and sells those 30 tablets for $190.00. What is the gross profit on this transaction?
$190.00 – $175.00 = $15.00
Best Pharmacy buys 4-mg Avandaryl tablets at $350.00 per 100 tablets. The pharmacy then sells a bottle of 60 tablets for $300.00.
$210.00
$90.00
Good Neighbor Pharmacy buys 90 Naprosyn 250-mg tablets for $16.00. Good Neighbor’s markup rate on this item is 25%. What is the selling price for 90 Naprosyn 250-mg tablets?
$16.00 + 0.25($16.00) = $20.00
Joe’s Pharmacy buys fluconazole 100 mg for $350.00 for 30 tablets. It costs $5.00 to dispense 30 tablets, and a bottle of 30 tablets sells for $435.00. What is the net profit on this transaction?
$80.00
Wholesale Rx Inc. offers Best Pharmacy a 26% discount on Effexor 25-mg tablets. The regular wholesale price for 120 Effexor 25-mg tablets is $270.00. What price did the pharmacy pay for 120 Effexor 25-mg tablets?
$270.00 – 0.26($270.00) = $199.80
The wholesaler Meds R Us offers Neighborhood Pharmacy 30 Nexium 20-mg capsules for $165.00. The regular wholesale price for Nexium 20-mg capsules is $195.00 for 30 capsules. What discount rate is being offered?
15%
The regular price of Lipitor 40 mg is $98.50 for 60 tablets. The pharmacy gets a 14% discount when buying from a wholesaler.
$98.50 – 0.14($98.50) = $84.71
$95.48 – $84.71 – $5.00 = $5.77
The AWP for Drug D 60 mg is $150.00 for 30 tablets. Neighborhood Pharmacy can purchase Drug D 60 mg for $120.00 for 30 tablets. It costs the pharmacy $6.00 to dispense the tablets.
$126.00
$160.00
$34.00
The AWP for Actonel 35 mg is $130.00 for 12 tablets. Joe’s Pharmacy can purchase Actonel 35 mg for $115.00 for 12 tablets. It costs the pharmacy $4.00 to dispense the tablets.
$115.00 + $4.00 = $119.00
$130.00 + 0.03($130.00) + $2.00 = $135.90
$135.90 – $119.00 = $16.90
The AWP for Levoxyl 100 mcg is $54.00 for 100 tablets.
The AWP for Levoxyl 100 mcg is $54.00 for 100 tablets. Joe’s Pharmacy can purchase 90 tablets for $45.00. It costs Joe $4.00 to dispense a prescription for 30 tablets. The insurance company will reimburse AWP + 3% + $3.00 dispensing fee. What is Joe’s profit in filling a prescription for 30 tablets of 100-mcg Levoxyl?
Joe’s cost: ($45.00/90 tablets) × 30 tablets = $15.00
Joe pays: $15.00 + $4.00 = $19.00
Insurance pays: $16.20 + 0.03($16.20) + $3.00 = $19.69
Joe’s profit: $19.69 – $19.00 = $0.69
In January, the staff at Joe’s Pharmacy performs an inventory and discovers that the value of the inventory is $80,000.00. Six months later, the staff performs another inventory and the value is $100,000.00. Over the course of a year, Joe spends $360,000.00 purchasing items to sell at the pharmacy.
Ralph’s Pharmacy purchases sinus caplets for $4.54/60 and sells them for $6.81/60.
$2.27
50%
The regular wholesale price for anti-itch ointment is $5.25/oz. A pharmacy buys anti-itch ointment from Prescriptions R Us for $4.00/oz.
Medicaid reimburses Small’s Pharmacy at 250% of the average acquisition cost of amoxicillin suspension plus a $4.35 professional fee. Small’s Pharmacy pays $2.45 for a 100-mL bottle, and the average acquisition cost is $2.75. It costs Bud Small $3.50 to fill the prescription.
$5.95
$11.23
$5.28
Blue Shield reimburses Small’s Pharmacy AWP plus a $7.50 professional fee for filling a generic prescription. The AWP for 100 furosemide 40-mg tablets is $17.80. Bud Small buys 100 furosemide tablets for $14.90, and his cost for filling the prescription is $3.25.