Oral and ParenteralMedication
Unit
Chapter 6
Calculating Oral Medication Doses
Chapter 7
Syringes
Chapter 8
Preparation of Solutions
Chapter 9
Parenteral Medications
103
(Photodisc/Getty Images)
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Chapter
104
Learning Outcomes
After completing this chapter, you will be able to
1. Calculate simple problems for oral medications in solid and liquid form.
2. Calculate complex problems for oral medications in solid and liquid form.
3. Calculate doses for medications measured in milliequivalents. 4. Interpret drug labels in order to calculate doses for oral medication.5. Calculate doses based on body weight.6. Calculate doses based on body surface area (BSA) using a formula or a
nomogram.
I n this chapter you will learn how to calculate doses of oral medications in solid or liq-
uid form.You will also be introduced to problems that utilize body weight or body sur-
face area (BSA) to calculate dosages.
Calculating Oral Medication Doses
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Simple Problems 105
Simple Problems
In the calculations you have done in previous chapters, all the equivalents havecome from standard tables, for example, 60 mg gr 1. In this chapter, theequivalent used will depend on the strength of the drug that is available; forexample 1 tab 15 mg. In the following examples, the equivalent is found onthe label of the drug container.
Medication in Solid Form
Example 6.1The order reads Cymbalta (duloxetine HCl) 120 mg PO daily.Read the drug label shown in � Figure 6.1. How many capsules of thisantidepressant drug will you administer to the patient?
=
=
Convert 120 mg to capsules.
Cancel the milligrams and calculate the equivalent amount in capsules.
Because the label indicates that each capsule contains 30 mg, you use the
unit fraction
So, you would give 4 capsules by mouth once a day to the patient.
Example 6.2The prescriber orders Diovan (valsartan) 120 mg PO once daily for a pa-tient with hypertension. Read the drug label shown in � Figure 6.2 anddetermine how many tablets you would give to the patient.
1204
mg *1 cap
301
mg= 4 cap
1 cap30 mg
120 mg *
? cap? mg
= ? cap
120 mg = ? cap
� Figure 6.1Drug label for Cymbalta.
(Copyright Eli Lilly and Company. Usedwith permission).
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106 Chapter 6 Calculating Oral Medication Doses
Convert 120 mg to tablets.
Cancel the milligrams and obtain the equivalent amount in tablets.
Because 1 tab 40 mg, the unit fraction is
So, you would give 3 tablets by mouth daily to the patient.
Example 6.3Read the label in � Figure 6.3. The physician’s order is Lotrel 5 mg/20 mgPO daily. How many capsules of this antihypertensive drug should beadministered per day?
1203
mg *1 tab
401
mg= 3 tab
1 tab40 mg
=
120 mg *
? tab? mg
= ? tab
120 mg = ? tab
.PX
ET
OL 3N1
50-4040-8700
100 capsulesRx only
NDC 0078-0404-05
Lotrel® 2.5/10amlodipine besylate(equivalent to amlodipine 2.5 mg)benazepril HCl 10 mg
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(Reproduced with the permission of Novartis Pharmaceuticals.)
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� Figure 6.2Drug label for Diovan.
(Reproduced with the permission of Novartis Pharmaceuticals.)
Lotrel is a combination drug (see Figures 2.16 and 2.17 in Chapter 2)composed of amlodipine and benazepril; therefore, for computationalpurposes we need only address the first listed drug (amlodipine).
Since the order requires 5 mg of amlodipine, convert the 5 mg to capsules.
Cancel the milligrams and obtain the equivalent amount in capsules.
The label indicates that 1 capsule contains 2.5 mg of amlodipine.
5 mg *
? cap? mg
= ? cap
5 mg = ? cap
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Simple Problems 107
Therefore, the fraction is
So, you would give 2 capsules by mouth daily to the patient.
Example 6.4The order is codeine sulfate grain q4h prn pain. The label reads per tablet. How many tablets should you give a patient?In this problem you want to convert the grain to tablets.
Cancel the grain and determine the equivalent amount in tablets.
Because the fraction is
Since 2 tablets contain grain of codeine sulfate, you would give 2 tabletsby mouth every 4 hours as necessary for pain.
Medication in Liquid FormSince pediatric and geriatric patients, as well as patients with neurological con-ditions, may be unable to swallow medication in tablet form, sometimes oralmedications are ordered in liquid form. The label states how much drug iscontained in a given amount of liquid.
Example 6.5The physician orders Lexapro (escitalopram oxalate) 10 mg POonce daily. Read the label in � Figure 6.4 and determine the number ofmilliliters you would administer to the patient.
Convert 10 milligrams to milliliters.
Cancel the milligrams and calculate the equivalent amount in mL.
10 mg *
? mL? mg
= ? mL
10 mg = ? mL
12
gr12
*1 tab
gr14
=1 tab
24
= 1 tab ,24
= 1 tab *42
= 2 tab
1 tab
gr 14
1 tab = gr 14 ,
gr 12
= ? tab
12
gr 14
12 PO
52
mg *1 cap
2.51
mg= 2 cap
1 cap2.5 mg
NOTE
Some liquid oralmedications are suppliedwith special calibrateddroppers or oral syringesthat are used only for thesemedications (e.g., digoxinand Lasix).
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108 Chapter 6 Calculating Oral Medication Doses
� Figure 6.4Drug label for Lexapro.
(Courtesy of Forest Pharmaceuticals, Inc.)
� Figure 6.5Drug label for Omnicef.
(Reproduced with Permission of Abbott Laboratories.)
Because the label indicates that every 5 mL of the solution contains
5 mg of Lexapro, use the unit fraction
So, you would give 10 mL by mouth once a day to the patient.
Example 6.6The physician orders Omnicef (cefdinir) 500 mg PO q12h. Read thelabel in � Figure 6.5. Determine the number of mL you would adminis-ter to the patient.
10 mg *5 mL5 mg
= 10 mL
5 mL5 mg
Convert 500 milligrams to mg.
Cancel the milligrams and calculate the equivalent amount in milliliters.
500 mg *
? mL? mg
= ? mL
500 mg = ? mL
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Simple Problems 109
Because the label indicates that every 5 mL of the solution contains
123 mg of Omnicef, use the unit fraction
So, you would give 20 mL by mouth every 12 hours to the patient.
Medications Measured in MilliequivalentsSome drugs are measured in milliequivalents, which are abbreviated as mEq. Phar-maceutical companies label electrolytes in milligrams as well as milliequivalents.
Example 6.7The physician orders K-Tab (potassium chloride) 30 mEq PO daily.Read the label in � Figure 6.6 and determine how many tablets of thiselectrolyte supplement you should administer.
5004
mg *5 mL
1251
mg= 20 mL
5 mL125 mg
� Figure 6.6Drug label for K-Tab.
(Reproduced with Permission of Abbott Laboratories.)
In this problem you want to change 30 mEq to tablets.
You can do this on one line as follows:
Because the label indicates that each tablet contains 10 mEq, the unit
fraction is
So, you would administer 3 tablets of K-Tab by mouth once daily.
303
mEq *1 tab
10 mEq= 3 tab
1 tab10 mEq
30 mEq *
? tab? mEq
= ? tab
30 mEq ¡ ? tab
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110 Chapter 6 Calculating Oral Medication Doses
Complex Problems
Sometimes dosage calculations will require that multiplication by unitfractions be repeated one or more times. Recall that we examined complexproblems in Chapter 3.
For example, if each tablet of a drug contains 2.5 mg, how many tablets wouldcontain 0.0025 gram?It helps to organize the information you will need for the computation as follows:
Given quantity: 0.0025 mgStrength:Quantity you want to find: ? tab
You do not know the direct equivalence between grams and tablets.This is a complex problem because you need to convert 0.0025 g to
milligrams and then convert milligrams to tablets.
So the problem is First, you want to cancel grams (g). To do this you must use an equivalencecontaining grams to make a unit fraction with grams in the denominator.
From the equivalence the unit fraction is
After the grams are cancelled, only milligrams remain on the left side.Now you need to change the milligrams to tablets. From the strength
2.5 mg 1 tab, the unit fraction is
After cancelling the milligrams, only tablets remain on the left side.Now complete your calculation by multiplying the numbers.
So, 1 tablet contains 0.0025 g.
Example 6.8The physician’s order is aspirin (acetylsalicylic acid) 600 mg PO stat. Thelabel reads gr 5 per caplet. How many caplets of this antipyretic drugshould be given to the patient?
0.0025 g *1,000 mg
1 g*
1 tab2.5 mg
=2.5 tab
2.5= 1 tab
0.0025 g *1,000 mg
1 g*
1 tab2.5 mg
= ? tab
1 tab2.5 mg
=
0.0025 g *1,000 mg
1 g= ? tab
1,000 mg1 g
1 g = 1,000 mg,
0.0025 g = ? tab
0.0025 g ¡ ? mg ¡ ? tab
1 tab = 2.5 mg
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Complex Problems 111
Given quantity: 600 mgStrength:Quantity you want to find: ? cap
There is no direct equivalence between milligrams and caplets.This is a complex problem because you need to convert 600 mg to grainsand then convert grains to caplets.
First change milligrams to grains. To do this, you must use an equiva-lence containing milligrams to make a unit fraction with milligrams inthe denominator. From the equivalence the
unit fraction is
After the milligrams are cancelled, only grains remain on the left side. Now you need to change the grains to caplets. From the strength
the unit fraction is
Now complete your calculation.
So, you should give 2 caplets by mouth immediately to the patient.
Example 6.9The order is Diflucan (fluconazole) 0.4 gram PO daily. Read the labelshown in � Figure 6.7 and calculate the number of tablets of this anti-fungal drug that should be given to the patient.
Given quantity: 0.4 gStrength:Quantity you want to find: ? tab
In this problem you want to convert 0.4 gram to milligrams and thenconvert milligrams to tablets.
0.4 g ¡ ? mg ¡ ? tab
1 tab = 100 mg
600
10 mg *
gr 1 60
1 mg
*
1 cap gr 5
=
10 cap5
= 2 caplets
600 mg *gr 1
60 mg*
1 capgr 5
= ? cap
1 capgr 5
.gr 5 = 1 cap,
600 mg *gr 1
60 mg= ? cap
gr 160 mg
.
gr 1 = 60 mg,
600 mg ¡ gr? ¡ ? cap
1 cap = gr 5
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112 Chapter 6 Calculating Oral Medication Doses
� Figure 6.8Drug label for Tikosyn.
(Reg.Trademark of Pfizer Inc. Reproducedwith permission.)
You can do this on one line as follows:
Because 1,000 mg 1 g, the first unit fraction is
Because 100 mg 1 tab, the second unit fraction is
So, you should give 4 tablets by mouth once a day to the patient.
Example 6.10The order is Tikosyn (dofetilide) 0.5 mg PO b.i.d. Read the labelshown in � Figure 6.8. Calculate how many capsules of this antifungaldrug should be given to the patient. Although there are two strengthson the label (mcg and mg), calculate the problem using microgramstrength.
Given quantity: 0.5 mgStrength:Quantity you want to find: ? cap
1 tab = 125 mcg
0.4 g *1,000
10mg
1 g*
1 tab100
1mg
= 4 tab
1 tab100 mg
=
1,000 mg1 g
=
0.4 g *
? mg? g
*
? tab? mg
= ? tab
� Figure 6.7Drug label for Diflucan.
(Reg.Trademark of Pfizer Inc. Reproducedwith permission.)
NOTE
Although Example 6.10would be simpler using themilligrams, we will do thecalculation usingmicrograms in order topractice complex problems.For safety purposes, drugmanufacturers often placeboth microgram andmilligram concentrations ondrug labels.
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Complex Problems 113
In this problem you want to convert 0.5 milligrams to microgramsand then convert micrograms to capsules.
You can do this on one line as follows:
Because 1,000 mcg 1 mg, the first unit fraction is
Because 1 cap 125 mcg, the second unit fraction is
So, you should give 4 capsules by mouth twice a day to the patient.
Example 6.11The order is Daypro (oxaprozin) 1.8 g PO once daily each morning. Thedrug is supplied as 600 mg per caplet. How many caplets of this anti-arthritic drug should be given the patient?
Given quantity: 1.8 gStrength:Quantity you want to find: ? cap
In this problem you want to convert 1.8 grams to milligrams and thenconvert milligrams to caplets.
You can do this on one line as follows:
Because 1,000 mg 1 g, the first unit fraction is
Because 1 cap 600 mg, the second unit fraction is
So, you should give 3 caplets by mouth to the patient once a day in themorning.
1.8 g *1,000 mg
1 g*
1 cap600 mg
=18
6 cap
= 3 cap
1 cap600 mg
=
1,000 mg1 g
=
1.8 g *
? mg? g
*
? cap? mg
= ? cap
1.8 g ¡ ? mg ¡ ? cap
1 cap = 600 mg
0.5 mg *1,000
8mcg
1 mg*
1 cap125
1mcg
= 4 cap
1 cap125 mcg
=
1,000 mcg1 mg
=
0.5 mg *
? mcg? mg
*
1 cap? mcg
= ? cap
0.5 mg ¡ ? mcg ¡ ? cap
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114 Chapter 6 Calculating Oral Medication Doses
� Figure 6.10Drug label for Indocin.
(The labels for the products Indocin 25mgper 5mL are reproduced with permission ofMerck & Co., Inc., copyright owner.)
Example 6.12The physician orders Norvir (ritonavir) 0.6 g PO q12 hours. Read thelabel in � Figure 6.9 and determine the number of mL of this protease in-hibitor your patient would receive.
Given quantity: 0.6 gStrength:The quantity you want to find: ? mL
In this problem you want to convert 0.6 grams to milligrams and thenconvert milligrams to milliliters.
You can do this on one line as follows:
Because 1,000 mg 1 g, the first unit fraction is
Because 1 mL 80 mg, the second unit fraction is
So, you would give 7.5 mL by mouth to the patient every 12 hours.
Example 6.13The order is Indocin (indomethacin) 75 mg PO daily in 3 divided doses.Read the label in � Figure 6.10 and determine the number of teaspoonsof this antiinflammatory drug you should administer.
0.6 g *1,000 mg
1 g*
1 mL80 mg
=608
mL = 7.5 mL
1 mL80 mg
=
1,000 mg1 g
=
0.6 g *
? mg? g
*
? mL? mg
= ? mL
0.6 g ¡ ? mg ¡ ? mL
80 mg>mL
Given quantity: 75 mgStrength:The quantity you want to find: ? t
In this problem you want to convert 75 milligrams to milliliters and thenconvert mL to teaspoons.
75 mg ¡ ? mL ¡ ? t
25 mg per 5 mL
� Figure 6.9Drug label for Norvir.
(Reproduced with Permission of AbbottLaboratories.)
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Calculating Dosage by Body Weight 115
You can do this on one line as follows:
Because 25 mg 5 mL, the first unit fraction is
Because 5 mL 1 t, the second unit fraction is
Because the order specifies “3 divided doses”, the 3 t must be dividedinto 3 equal amounts over 24 hours. Therefore, each dose would be 1teaspoon (25 mg), and you would give 1 teaspoon of Indocin by mouthto the patient every 8 hours.
Calculating Dosage by Body Weight
Sometimes the amount of medication is prescribed based on the patient’s bodyweight. A patient who weighs more will receive a larger dose of the drug, anda patient who weighs less will receive a smaller dose of the drug.
Example 6.14The prescriber orders 15 milligrams per kilogram of a drug for a patientwho weighs 80 kilograms. How many milligrams of this drug should thepatient receive?
Body weight: 80 kgOrder:Find: ? mg
Convert body weight to dosage.
Since the order is 15mg/kg, you use the unit fraction
Therefore, the patient should receive 1,200 mg of the drug.
Example 6.15The prescriber orders Klonopin (clonazepam) 0.05 mg/kg PO daily in threedivided doses for a patient who weighs 60 kilograms. If each tablet contains1 mg, how many tablets of this anticonvulsant drug should the patient re-ceive per day? How many tablets would the patient receive per dose?
80 kg *
15 mg1 kg
= 1,200 mg
15 mg1 kg
80 kg (of body weight) *
? mg (of drug)? kg (of body weight)
= ? mg (of drug)
80 kg (of body weight) ¡ ? mg (of drug)
15 mg>kg
75 mg *5 mL25 mg
*1 t
5 mL=
7525
t or 3 t
1 t5 mL
=
5 mL25 mg
=
75 mg *
? mL? mg
*
? t? mL
= ? t
NOTE
In Example 6.13, the orderstates “in three divideddoses.”This instructs thepractitioner to separate thetotal daily dose into 3 equalparts over a 24-hour period.To ensure even distributionof the medication, thefrequency of the dosesshould also be regular andconsistent, so the drug isadministered every 8 hours.
NOTE
The expression 15 mg/kgmeans that the patient is toreceive 15 milligrams of thedrug for each kilogram ofbody weight.Therefore, youwill use the equivalent15 mg (of drug) 1 kg (of body weight).
=
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116 Chapter 6 Calculating Oral Medication Doses
Body weight: 60 kgOrder:Strength:Find: ? tab
When drugs are prescribed based on body weight, you generally start theproblem with the weight of the patient. You first change the single unit ofmeasurement, kilograms (kg of body weight), to another single unit of mea-surement, milligrams (mg of drug), and then convert the milligrams to tablets.
Because the order is for 0.05 mg per kg, the first unit fraction is
Since each tablet contains 1 mg, the second unit fraction is
The patient should receive 3 tablets of Klonopin by mouth per day in 3 di-vided doses, and therefore the patient should receive 1 tablet every 8 hours.
Example 6.16The physician orders Biaxin (clarithromycin) 7.5 milligrams per kilo-gram PO b.i.d. If the drug strength is 250 milligrams per 5 mL, howmany mL of this antibiotic drug should be administered to a patient whoweighs 70 kilograms?
Body weight: 70 kgOrder:Strength:Find: ? ml
Convert body weight to dosage.
Since the order specifies 7.5 mg per kg, the first fraction is
Since the strength is 250 mg per 5 mL, the second fraction is
The patient should receive 10.5 mL of Biaxin by mouth 2 timesper day.
70 kg *7.5 mg
kg*
5 mL250 mg
= 10.5 mL
5 mL250 mg
7.5 mLkg
70 kg *
? mg? kg
*
? mL? mg
= ? mL
70 kg ¡ ? mg ¡ ? mL
250 mg>5 mL7.5 mg>kg
60 kg *0.05 mg
1 kg*
1 tab1 mg
= 3 tabs
1 tab1 mg
0.05 mg1 kg
.
60 kg(of body weight)
*
? mg (of drug)? kg (of body weight)
*
? tab? mg (of drug)
= ? tab
60 kg (of body weight) ¡ ? mg (of drug) ¡ ? tab
1 tab = 1 mg0.05 mg>kg
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Calculating Dosage by Body Surface Area 117
Calculating Dosage by Body Surface Area
In some cases, body surface area (BSA) may be used rather than weight indetermining appropriate drug dosages. This is particularly true when calcu-lating dosages for children, those receiving cancer therapy, burn patients,and patients requiring critical care. A patient’s BSA can be estimated by usingformulas or nomograms.
BSA FormulasBody surface area can be approximated by formula using either a hand-held calculator or an online website. BSA, which is measured in squaremeters can be determined by using either of the following twomathematical formulas:
Formula for metric units:
Formula for household units:
Example 6.17Find the BSA of an adult who is 183 cm tall and weighs 92 kg.Because this example has metric units (kilograms and centimeters), weuse the following formula:
At this point we need a calculator with a square root key.
Therefore, the BSA of this adult is
Example 6.18What is the BSA of a man who is 4 feet 10 inches tall and weighs142 pounds?First you convert 4 feet 10 inches to 58 inches.
2.16 m2.
= 2.16256
= 24.6767
= A92 * 1833,600
BSA = Aweight in kilograms * height in centimeters3,600
BSA = Aweight in pounds * height in inches3,131
BSA = Aweight in kilograms * height in centimeters3,600
1m22,
NOTE
In Example 6.17, the metricformula for BSA was used,and in Example 6.18, thehousehold formula for BSAwas used. However, eachformula provided the BSAmeasured is square meters(m2 ). In this book, we willround off BSA to twodecimal places.
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118 Chapter 6 Calculating Oral Medication Doses
Because the example has household units (pounds and inches), we usethe following formula:
Therefore, the BSA of this adult is
NomogramsBSA can also be approximated by using a chart called a nomogram (� Figure 6.11).The nomogram includes height, weight, and body surface area. If a straight lineis drawn on the nomogram from the patient’s height (left column) to the patient’sweight (right column), the line will cross the center column at the approximateBSA of the patient. Before handheld calculators were used, the nomogram wasthe best tool available for determining BSA. Since electronic technology hasbeen incorporated into most health care settings to ensure more accurate mea-surements, nomograms are becoming obsolete.
In Example 6.17 we used the formula to calculate the BSA of an 183 cm,92 kg patient to be 2.16 m2. Now let’s use the adult nomogram to do thesame problem. In � Figure 6.12, you can see that the line from 183 cm to 92kg intersects the BSA column at about 2.20 m2.
In Example 6.18, by using the formula we calculated the BSA of a 4 ft10 in, 142 lb patient to be 1.62 m2. If we use the adult nomogram todetermine the BSA (� Figure 6.13), we get 1.59 m2.
Example 6.19The physician orders of a drug PO once daily. How many mil-ligrams of the drug would you administer to an adult patient weighing88 kg with a height of 150 cm?
The first step is to determine the BSA of the patient. This can be done byformula or nomogram.
Using the formula, you get
Using the adult nomogram, you get 1.81 m2. So, you can use either1.91 m2 or 1.81 m2 as the BSA. If you choose to use 1.81 m2, you wantto convert BSA to dosage in mg.
BSA:Order:Find: ? mg
1.81 m2*
? mg
m2 = ? mg
1.81 m2= ? mg
40 mg>m21.81 m2
= 1.91 m2 = 23.6667
BSA = A88 * 1503,600
40 mg>m2
1.62 m2. = 1.62187
= 226,305
= A142 * 583,131
BSA = Aweight in pounds * height in inches3,131
NOTE
Whether formulas ornomograms are used toobtain body surface area,the results are onlyapproximations.Thisexplains why we obtainedboth 2.16 m2 (using theformula) and 2.20 m2 (usingthe nomogram) as the BSAfor the same patient inExample 6.17. This alsooccurred in Example 6.18,where the BSA was 1.62 m2
(using the formula) and 1.59 m2 (using thenomogram).
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Calculating Dosage by Body Surface Area 119
cm 200 79 inch78777675747372
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cm 100
HEIGHT
2.80 m2
2.70
2.60
2.50
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2.30
2.20
2.10
2.001.951.90
1.85
1.80
1.75
1.70
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1.00
0.95
0.90
0.86 m2
BODY SURFACE AREA
330 lbkg 150
145140
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66 lb
WEIGHT
� Figure 6.11Adult nomogram.
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120 Chapter 6 Calculating Oral Medication Doses
cm 200 79 inch78777675747372
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HEIGHT
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2.001.951.90
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1.75
1.70
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1.30
1.25
1.20
1.15
1.10
1.05
1.00
0.95
0.90
0.86 m2
BODY SURFACE AREA
330 lbkg 150
145140
135
130
125
120
115
110
105
100
95
90
85
80
75
70
65
60
55
50
45
40
35
kg 30
320310300290
280270
260
250
240
230
220
210
200
190
180
170
160
150
140
130
120
110
105
100
95
90
85
80
75
70
66 lb
WEIGHT
� Figure 6.12Nomogram for Example 6.17.
OLSEMC06_103-137hr2 6/12/06 2:53 PM Page 120
Calculating Dosage by Body Surface Area 121
cm 200 79 inch78777675747372
7170
69
68
67
66
6564
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39 in
195
190
185
180
175
170
165
160
155
150
145
140
135
130
125
120
115
110
105
cm 100
HEIGHT
2.80 m2
2.70
2.60
2.50
2.40
2.30
2.20
2.10
2.001.951.90
1.85
1.80
1.75
1.70
1.65
1.60
1.55
1.50
1.45
1.40
1.35
1.30
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1.20
1.15
1.10
1.05
1.00
0.95
0.90
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BODY SURFACE AREA
330 lbkg 150
145140
135
130
125
120
115
110
105
100
95
90
85
80
75
70
65
60
55
50
45
40
35
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320310300290
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260
250
240
230
220
210
200
190
180
170
160
150
140
130
120
110
105
100
95
90
85
80
75
70
66 lb
WEIGHT
� Figure 6.13Nomogram for Example 6.18.
OLSEMC06_103-137hr2 6/12/06 2:53 PM Page 121
122 Chapter 6 Calculating Oral Medication Doses
Since the order is the unit fraction is
If you use the BSA of 1.91 m2, the calculations are similar.
So, if you use 1.81 m2, you would administer 72.4 mg. However if youuse 1.91 m2, you would administer 76.4 mg of the drug to the patient.
Example 6.20The prescriber ordered of a drug PO stat for a patient whohas a BSA of 1.65 m2. The “safe dose range” for this drug is 20 to 40 mgper day. Calculate the prescribed dose in milligrams and determine if it iswithin the safe range.
BSA:Order:Find: ? mg
You want to convert the BSA of 1.65 m2 to the number of milligrams ordered.
Because the order is 30 mg per m2, the unit fraction is
The safe dose range is 20–40 mg per day.
So, the dose prescribed, 49.5 mg, is higher than the upper limit (40 mg) ofthe daily “safe dose range.” Therefore, the prescribed dose is not safe, andyou would not administer this drug. You would consult with the prescriber.
Example 6.21The order is Trexall (methotrexate) PO q12h for three doses.How many scored 5 mg tablets of this antineoplastic drug would you ad-minister to patient with a BSA of 2.29 m2?
BSA:Order:Strength:Find: ? tab
Convert the body surface area to tablets.
2.29 m2*
? mg
m2 *
? tab? mg
= ? tab
2.29 m2¡ ? mg ¡ ? tabs
1 tab = 5 mg3.3 mg>m2
2.29 m2
3.3 mg>m2
1.65 m 2
*
30 mg
m 2 = 49.5 mg
30 mg
m2
1.65 m2*
? mg
m2 = ? mg
1.65 m2= ? mg
30 mg>m2
1.65 m2
30 mg>m2
1.91 m 2
*
40 mg
m 2 = 76.4 mg
1.81 m 2
*
40 mg
m 2 = 72.4 mg
40 mg
m240 mg>m2,ALERT
Before a medication isadministered, it is theresponsibility of the healthcare practitioneradministering themedication to check thesafe dosage andadministration range for thedrug in the Physicians’ DeskReference (PDR), in adesignated drug book, orwith the pharmacist.
OLSEMC06_103-137hr2 6/12/06 2:53 PM Page 122
Case Study 6.1 123
Because the order is the first unit fraction is
Because 1 scored tablet contains 5 mg, the second unit fraction is
The patient should receive scored tablets of Trexall by mouth every12 hours for 3 doses.
112
2.29 m 2 *3.3 mg
m 2 *1 tab5 mg
= 1.51 tabs
1 tab5 mg
.
3.3 mg
m2 .3.3 mg>m2,
SummaryIn this chapter, you learned the computations nec-essary to calculate dosages of oral medications inliquid and solid form.
Calculating doses for oral medications in solidand liquid form■ The label states the strength of the drug
(e.g., ).■ Sometimes oral medications are ordered in
liquid form for special populations such aspediatrics, geriatrics, and patients withneurological conditions.
■ Special calibrated droppers or oral syringes that are supplied with some liquid oral medica-tions may be used to administer only those medications.
■ Some drugs, such as electrolytes, are measured inmilliequivalents (mEq).
Calculating doses by body weight■ Dosages based on body weight are generally
measured in milligrams per kilogram ■ Start calculations with the weight of the patient.■ Medications may be prescribed by body weight in
special populations such as pediatrics and geriatrics.■ It is crucial to ensure that every medication adminis-
tered is within the recommended safe dosage range.
Calculating doses by body surface area■ Body surface area (BSA) is measured in square
meters (m2).■ Start calculations with the BSA of the patient.■ BSA is determined by using either a formula or a
nomogram.■ BSA may be utilized to determine dosages for spe-
cial patient populations such as those receivingcancer therapy, burn therapy, and for patients re-quiring critical care.
(mg/kg).
15 mg/mL10 mg/tab,
Mr. M. is a 68-year-old male patient with a pastmedical history of diabetes mellitus Type II andsevere ischemic cardiomyopathy. He reportedthat for 6 weeks he had been experiencingshortness of breath and fatigue with moderateactivity, difficulty sleeping at night, and has aweight gain of 5 lbs, even though he describedhis appetite as poor. There is no evidence ofsmoking or illegal drug use. Upon examination,the practitioner noted periorbital edema and bi-
lateral pitting edema in both lower extremi-ties. His present weight is 154 lb and his vitalsigns are BP T 98.4, P 104, and R 28.Mr. M. was admitted for intravenous supportand aggressive diuresis.
His orders are as follows:■ Complete CBC and SMA18■ Coronary angiogram; ECG; stress perfusion
scan; chest X-ray.
160>100,
4+
Case Study 6.1
OLSEMC06_103-137hr2 6/12/06 2:53 PM Page 123
124 Chapter 6 Calculating Oral Medication Doses
Practice Reading LabelsCalculate the following doses using the labels shown. You will find the answers in Appendix A in the backof the book.
1. Lopressor (metoprolol) 0.05 gram __________ tab 2. Wellbutrin (bupropion hydrochloride) 200 mg ________ tab==
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■ Low-salt diet (2 g day)■ Lasix (furosemide) 80 mg PO stat■ Lasix (furosemide) 60 mg PO q12h to begin
12 hours after the stat dose■ Digoxin 0.25 mg PO once daily■ Micro-K 10 Extencaps (potassium chloride)
20 mEq PO daily■ Diabinese (chlorpropamide) 125 mg PO each
morning with breakfast■ Colace (docusate sodium) 100 mg PO t.i.d.■ Ativan (lorazepam) 3 mg PO HS■ Fluid restriction 1,500 mL 24 h■ Strict intake and output■ Foley catheter to bedside drainage
1. The patient drank 650 mL of H2O, 150 mL ofcranberry juice, and 200 mL of ginger ale dur-ing the 7 A.M. to 7 P.M. shift. How many mL offluid may the patient can be given over thenext 12 hours?
2. At 8 P.M., Mr. M.’s wife fed him cups of anorganic brand of chicken broth, which con-tains 390 mg salt in each 1 cup serving.(a) How many mL of chicken broth did the
patient receive? (b) How many grams of salt did he consume?(c) How much more salt should Mr. M. con-
sume for the remainder of the day?
3. The diuretic drug Lasix (furosemide) is avail-able in 20 mg tablets.(a) How many tablets will you administer for
the stat dose?(b) How many tablets will the patient have re-
ceived within the first 20 hours?4. How many milliequivalents of the electrolyte
supplement micro-K will the patient have re-ceived after 5 days of therapy?
5. Colace (docusate sodium), a stool-softeningdrug, is supplied as an oral liquid, 20 mg 5 mL.(a) How many times a day does the patient re-
ceive this medication?(b) How many mL would the patient receive
in two days?6. The available strength of Ativan (lorazepam)
is 1 mg tab. How many tablets of this sedativecontain the prescribed dose?
7. The cardiac drug digoxin is supplied in the fol-lowing strengths: 50 mcg, 100 mcg, and 200 mcgtablets. Which combination of tablets wouldyield the least number of tablets that woulddeliver the prescribed dose?
8. Mr. M. remains hospitalized for one week.(a) How many milligrams of Diabinese (chlor-
propamide) would he have received by theend of the first seven days?
(b) The Diabinese is available in 250 mg scoredtablets. How many tablets would Mr. M.have received by the end of the seven days?
>
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OLSEMC06_103-137hr2 6/12/06 2:54 PM Page 124
Practice Reading Labels 125
3. Cymbalta (duloxetine HCl) 0.04 g ____________ cap
4. Prozac (fluoxetine) 40 mg ____________ mL
5. Ery-Tab (erythromycin) 0.666 g ____________ cap
6. Gleevec (amatinib mesylate) 800 mg ____________ tab
7. Symbyax (olanzapine fluoxetine) 12mg 50mg ________ cap
8. quinidine gluconate 20 mg ____________ mL
9. Epivir (lamivudine) 0.6 g ____________ tab
10. Retrovir (zidovudine) 100 mg ____________ mL
11. Lanoxin (digoxin) 125 mcg ____________ mL
12. Lanoxicap (digoxin) 0.2 mg ____________ cap=
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4153827 A000747 Rev. 3/03 240 mL
=
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Manufactured under agreement from Shire PharmaceuticalsGroup plcBasingstoke, UK
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OLSEMC06_103-137hr2 6/12/06 2:54 PM Page 125
126 Chapter 6 Calculating Oral Medication Doses
13.Toprol –XL (metoprolol succinate) 0.4 g ____________ tab
14. Plendil (felodipine SR) 5 mg ____________ tab
15. Atacand HCT (candesartan cilexetil) 16 mg ___________ tab
16. Prilosec (omeprazole) 80 mg ____________ cap
17. Lopressor (metoprolol) 0.05 mg ____________ mL
18. Lotrel (amlodipine) 5/20 mg ____________ cap
19. Sandostatin (octreotide) 0.1 mg ____________ mL
20. Diovan (valsartan) 0.08 g ____________ mL
21. Norvir (ritonavir) 130 mg ____________ mL
22. Zonegran (zonisamide) 75 mg ____________ cap=
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metoprolol tartrate injection, USP5 mg per 5 mLFor Intravenous Use Rx only(5 mL ampul)Mfd. by: Novartis Pharma Stein AGStein, Switzerland forNovartis Pharmaceuticals Corp.East Hanover, NJ 0793685052702 © Novartis484270 US 484275
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OLSEMC06_103-137hr2 7/12/06 2:29 PM Page 126
Practice Reading Labels 127
23. Avandia (rosiglitazone) 8 mg ____________ tab
24. Lanoxin (digoxin) injection 400 mcg ____________ mL
25. Epivir (lamivudine) 300 mg ____________ tab
26.Valtrex (valocyclovir) 2 grams ____________ caplets
27. Clorazil (clozapine) 150 mg ____________ tab
28. Halcion (triazolam) 0.25 mg ____________ tab
29. Clozaril (clozapine) 75 mg ____________ tab
30.Vibramycin 100 mg ____________ mL
31. Cipro (ciprofloxacin) 0.5 g ____________ tab
32. Lithium Carbonate 900 mg ____________ tab
33. Levitra (vardenafil) 2500 mcg ____________ tab=
=
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Manufactured under agreement from Shire PharmaceuticalsGroup plcBasingstoke, UK
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OLSEMC06_103-137hr2 7/12/06 2:29 PM Page 127
34. Zometa (zoledronic acid) 4 mg ____________ mL
35. Norvasc (amlodipine) 10 mg ____________ tab
36. Detrol (tolterodine) 4 mg ____________ tab
37. Zyvox (linezolid) 400 mg ____________ mL
38. Provera (medroxyprogesterone) 20 mg ____________ tab
39. Zyvox (linezolid) 0.6 g ____________ tab
40. Zoloft (sertraline) 200 mg ____________ tab
41. Glucotrol XL (glipizide) 10 mg ____________ tab
42. Norvasc (amlodipine) 5 mg ____________ tab
43. OxyContin (oxycodone) 80 mg ____________ tab=
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OLSEMC06_103-137hr2 7/12/06 2:30 PM Page 128
Practice Reading Labels 129
44. Strattera (atomoxetine) 75 mg ____________ cap
45. Zithromax (azithromycin) 1,000 mg ____________ mL
46. Atarax (hydroxyzine) 50 mg ____________ tab
47.Terramycin (oxytetracycline HCl) 500 mg ____________ tab
48. Cardura (doxazosin) 16 mg ____________ tab
49. Rimadyl (carprofen) 75 mg ____________ tab
50. Biaxin (clarithromycin) 0.5 gram ____________ tab
51. Celexa (citalopram) 20 mg ____________ tab
52. naproxen 375 mg ____________ mL
53. methadone HCl 8 mg ____________ mL=
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OLSEMC06_103-137hr2 6/12/06 2:55 PM Page 129
54. torsemide 20 mg ____________ tab
55.Vistaril 75 mg ____________ mL
56. prednisone 80 mg ____________ tab
57. diclofenac 100 mg ____________ tab
58. Avelox (moxifloxacin HCl) 0.4 g ____________ tab
59. Emend (aprepitant) 0.08 g ____________ cap
60. Crixivan (indinavir sulfate) 0.8 g ____________ cap=
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130 Chapter 6 Calculating Oral Medication Doses
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OLSEMC06_103-137hr2 6/12/06 2:55 PM Page 130
Practice Sets 131
Practice Sets
The answers to Try These for Practice, Exercises, and Cumulative Review ap-pear in Appendix A at the end of the book. Ask your instructor for answers tothe Additional Exercises.
Try These for PracticeTest your comprehension after reading the chapter.
1. The order is Accupril (quinapril HCl) 30 mg PO b.i.d.(a) Read the label in � Figure 6.14 to determine how many tablets of this
antihypertensive drug you will administer.(b) Express the daily dose in grams.
� Figure 6.15Drug label for Erythromycin.
(Reproduced with Permission of AbbottLaboratories.)
2. The physician orders Trexall (methotrexate) PO twice per weekto treat leukemia. How many milligrams would you administer in oneweek if the patient is 150 centimeters tall and weighs 70 kg?
3. The physician ordered E.E.S (erythromycin ethylsuccinate) 300 mg POq6h. Read the label in � Figure 6.15. How many mL of this antibacterialdrug will the patient receive in 24 hours?
25 mg>m2
4. A physician’s order reads: Lyrica (pregabalin) 50 mg PO t.i.d. The bottlecontains 25-mg capsules. How many capsules of this anticonvulsive med-ication would you administer in 24 hours?
5. The physician orders Mellaril (thioridazine HCl) 80 mg PO t.i.d. for a pa-tient with schizophrenia. If you have 10, 15, and 50 mg nonscored tabletsto chose from, which combination of tablets would contain the exactdosage with the smallest number of tablets?
Workspace
� Figure 6.14Drug label for Accupril.
(Reg.Trademark of Pfizer Inc. Reproduced withpermission.)
OLSEMC06_103-137hr2 6/12/06 2:55 PM Page 131
132 Chapter 6 Calculating Oral Medication Doses
ExercisesReinforce your understanding in class or at home.
1. Paxil (paroxetine HCl) 40 mg PO daily has been ordered for your patient.Each tablet contains 0.02 gram. How many tablets of this antidepressantwill you prepare?
2. The physician prescribes 500 mcg of Baraclude (entecavir) per day via NG(nasogastric tube) for a patient with chronic hepatitis B virus infection.The oral solution contains 0.05 mg of entecavir per milliliter. How manymL of this antiviral medication would you deliver?
3. The order reads Prilosec (omeprazole) 40 mg PO once daily for 4 weeks.Read the drug label in � Figure 6.16 and determine the total number ofdelayed-release capsules of this antacid drug you would administer to thepatient over the entire treatment period.
4. The prescriber ordered Precose (acarbose) 75 mg PO t.i.d. with meals. The medication is available in 25 mg tablets. How many tablets of this
glucosidase inhibitor (antidiabetic agent) will you give your patient in 24 hours?
5. Toprol-XL (metoprolol succinate) extended-release tablets 200 mg POdaily has been prescribed for a patient. After reading the label in� Figure 6.17, how many tablets of this antihypertensive drug would thepatient have received after 7 days?
a
� Figure 6.17Drug label for Toprol-XL.
(Courtesy of AstraZeneca Pharmaceuticals LP.)
6. Keftab (cephalexin) is prescribed for an elderly patient who weighs 40 kilograms. The order is 50 milligrams per kilogram PO in two equallydivided doses. Each tablet contains 500 mg. How many tablets of thiscephalosporin antibiotic will the patient receive per dose?
Workspace
� Figure 6.16Drug label for Prilosec.
(Courtesy of AstraZeneca Pharmaceuticals LP.)
OLSEMC06_103-137hr2 6/12/06 2:55 PM Page 132
Practice Sets 133
Workspace7. Zyvox (linezolid) 600 mg PO q12h has been prescribed for an elderly pa-
tient with pneumonia. Read the label in � Figure 6.18 and determine howmany milliliters of the antibacterial suspension you would administer.
� Figure 6.18Drug label for Zyvox.
� Figure 6.19Drug label for Antivert.
(Reg.Trademark of Pfizer Inc. Repro-duced with permission.)
8. A patient is scheduled to receive 0.015 g of a drug by mouth every morn-ing. The drug is available as 7.5 mg tablets. How many tablets would youadminister?
9. A patient with osteoarthritis is ordered Voltaren (diclofenac sodium) 150 mgPO per day in 3 divided doses. There are 25-milligram tablets available.How many tablets will you give in a single dose?
10. An elderly patient with depression is ordered Aventyl (nortriptyline HCl) 25 mgPO t.i.d. The label reads Aventyl Oral Solution How many mLwill you administer?
11. Antivert (meclizine HCl) 25 mg PO once daily for three days has been or-dered for a patient with a history of motion sickness who is planning ex-tensive traveling. Read the information on the label in � Figure 6.19 andcalculate the number of scored tablets that the patient will receive whenthe prescription is completed at the end of the three days.
10 mg>5 mL.
12. The physician orders 7.5 mg of Tranxene SD (clorazepate dipotassium) POt.i.d. for an elderly patient with extreme anxiety. This drug is availablein 15 mg scored tablets. How many tablets would the patient receive in24 hours?
13. A patient develops a mild skin reaction to a transfusion of a unit of packedred blood cells and is given 75 milligrams of Benadryl (diphenhydramineHCl) PO stat. The only drug strength available is 25 mg capsules. Howmany capsules will you give?
14. The physician orders two Tylenol #3 (codeine 30 mg, acetaminophen300 mg) PO every 6 hours for a postpartum patient experiencing discom-
OLSEMC06_103-137hr2 7/12/06 2:41 PM Page 133
134 Chapter 6 Calculating Oral Medication Doses
fort from afterpains. How many milligrams of acetaminophen will thepatient have received by the end of the day?
15. The physician orders Detrol LA (tolterodine tartrate) 4 mg PO daily for apatient with an overactive bladder. Read the label in � Figure 6.20 anddetermine how many tablets you will give this patient.
� Figure 6.20Drug label for Detrol LA.
16. A patient with difficulty sleeping is medicated for insomnia with 0.25 g POat bedtime of a sedative drug. The drug is available as 500 mg per scoredtablet. How many tablets will you administer to your patient?
17. The physician orders Coumadin (warfarin sodium) 6.5 mg PO every otherday from Monday through Sunday. How many milligrams of Coumadinwill your patient receive in that week?
18. A physician is treating a patient for H. influenzae. He writes the followingprescription:
Vantin (cefpodoxime proxetil) 200 mg PO q12h for 14 days
Read the label in � Figure 6.21 and determine how many mL you will givethis patient.
� Figure 6.21Drug label for Vantin.
19. The physician orders Deltasone (prednisone) PO daily as partof the treatment protocol for a patient with leukemia.(a) How many milligrams of this steroid drug would you administer if the
patient is 5 feet 6 inches tall and weighs 140 pounds?(b) The drug is supplied in 50 mg per tablet. How many tablets will you
administer?20. The antibiotic, Zithromax (azithromycin), is ordered to treat a patient
with a bacterial exacerbation of Chronic Obstructive Pulmonary Disease(COPD). The order is:
Zithromax (azithromycin) 500 mg PO as a single dose on day one, followed by 250 mg once daily on days 2 through 5
How many milligrams will the patient receive by the completion of theprescription?
60 mg>m2
Workspace
OLSEMC06_103-137hr2 7/12/06 2:42 PM Page 134
Practice Sets 135
WorkspaceAdditional ExercisesNow, test yourself!
1. A drug (40 mg PO daily) has been ordered for your client. Each tablet con-tains 0.02 grams. How many tablets of this drug will you prepare?
2. The physician ordered a drug (0.55 mg kg PO). The patient weighs 32kilograms. The drug is supplied with a strength of Calculatethe number of milliliters you would administer.
3. Glucophage (metformin) 850 mg PO ac breakfast and dinner has been pre-scribed for your client. What is the patient’s daily dose expressed in grams?
4. Prescriber’s order:
Micronase (glyburide) 5 mg PO with breakfast
Each tablet contains 2.5 mg. How many tablets will you prepare?
5. Ditropan XL (oxybutynin chloride) 20 mg per day PO for 5 days has beenprescribed for a patient. Each tablet contains 5 mg. How many tablets ofthis anticholinergic medication will the patient receive by the end of thetreatment?
6. Norvasc (amlodipine) 5 mg PO once daily for 7 days has been ordered fora patient with angina. Each tablet contains 0.0025 grams. How manytablets will you administer to this patient for the week?
7. Vasotec (enalapril maleate) 7.5 mg PO daily has been prescribed. Tabletsavailable are 2.5 mg, 5 mg, 10 mg, and 20 mg. Which combination oftablets would yeld the least number of tablets that would deliver this ACE-inhibiting antihypertensive drug?
8. Alprazolam 0.5 mg PO t.i.d. has been prescribed for your client. Read theinformation on the label in � Figure 6.22. How many mL of this antianxi-ety drug will you administer to your patient?
30 mg>mL.>
9. A patient is to receive 0.01 g PO qhs of a drug. Each tablet contains 0.005 g.How many tablets will you administer to your patient?
10. Order:
Coumadin (warfarin sodium) 2.5 mg PO Monday, Wednesday, and Friday and 1 mg PO Tuesday, Thursday, Saturday, and Sunday
How many milligrams of Coumadin will your patient receive in one week?
� Figure 6.22Drug label for Alprazolam Intensol.
(Courtesy of Roxane Laboratories Inc.)
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136 Chapter 6 Calculating Oral Medication Doses
11. A drug (0.5 g PO stat) has been ordered for your patient. Each tabletcontains 0.25 gram. How many tablets of this drug will you give toyour patient?
12. Decadron (dexamethasone) 3 mg PO q12 h has been ordered for a patient.The drug is supplied in 1.5 mg tablets. Calculate the number of tablets ofthis steroid that the patient will receive in 24 hours.
13. Physician’s order:
furosemide 80 mg PO daily
The drug is supplied in 20 mg tablets. What would the patient’s daily dosebe if it were expressed in grams?
14. Physician’s order:
Pavabid (papaverine) 300 mg PO q12h
Each tablet contains 0.15 g. How many tablets would you administer?
15. Prescriber’s order:
Motrin (ibuprofen) 600 mg PO q8h for five days only
Each caplet contains 200 mg. How many caplets will you give this patientin the 5 days?
16. The antigout medication colchicine 1.2 mg PO q1h for 8 doses has beenordered. Each tablet contains 0.6 mg. How many milligrams of colchicinewill the patient receive in eight hours?
17. Physician’s order:
Cytovene (ganciclovir) 500 mg PO q3h while awake
The drug is available in 250 mg capsules. How many capsules will youadminister?
18. The physician ordered Retrovir (zidovudine) PO, an antiviral drug usedfor the treatment of CMV retinitis. The order is every 8 hours.The patient weighs 60 kg and is 140 cm in height. How many milligramsof this drug will you give the patient per day? (Use the formula for BSA.)
19. Physician’s order: Cytoxan (cyclophosphamide) 3 mg kg twice weekly.The client weighs 148 lb. The drug is supplied in 50 mg tablets. Howmany tablets will you prepare?
20. Physician’s order: prednisone 40 mg PO q12h for 5 days for a patient withacute asthma. The drug is supplied in 20 mg tablets. How many tabletswill you give this patient?
Cumulative Review Exercises
Review your mastery of earlier chapters.
1. Physician’s order: atropine sulfate gr PO now
Each tablet contains 0.4 mg. How many tablets will you prepare for yourpatient? _________
1/150
>
160 mg>m2
Workspace
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Cumulative Review Exercises 137
Workspace2. Lorabid (loracarbef) 400 mg PO q12h. The label reads 200 mg in 5 mL.
How many mL will you give your patient? _________
3. Azithromycin 0.2 g PO has been ordered. Convert this dose to grains._________
4. 0.4 g _________ mg
5. 2.5 liters _________ milliliters
6. 7 lb 11 oz _________ g
7. 1 pint _________ cups
8. The order reads of a drug PO. The patient weighs 72 kg and is70 in tall. The label reads How many mL will you administerto this patient? Use the nomogram to estimate the BSA.
9. A physician orders Tylenol (acetamenophen) 650 mg PO q8h. The labelreads as follows: Each capsule contains 325 mg. How many capsules willyou give this patient?
10. The order reads Tenormin (atenolol) 100 mg PO daily. Each tablet con-tains 0.025 g. How many tablets will you prepare?
11. The physician orders Parlodel (bromocriptine mesylate), 7.5 mg PO b.i.d.with meals. Each tablet contains 2.5 mg. How many tablets of this anti-Parkinsonian drug will you prepare?
12. A patient must receive 60 mEq of potassium chloride PO stat. Each tabletis labeled How many tablets will you prepare?
13. 200 mg _________ g
14. A patient must receive Videx (didanosine) PO. The patientweighs 90 kg. How many tablets will the patient receive if each tablet con-tains 100 mg?
15. 1 t _________ mL=
2.2 mg>kg
=
20 mEq>tab.
50 mg>mL.267 mg>m2
=
=
=
=
Animated examples, interactive practice questions with animated solutions, and challenge tests for thischapter can be found on the Prentice Hall Dosage Calculation Tutor that accompanies this text.Addi-tional, unique, interactive resources and activities can be found on the Companion Website.
MediaLinkwww.prenhall.com/olsen
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