Calculations I

Question 1

What are some of the different ways that drugs can be measured?

Answer 1

• Weight [g, mg, kg…]
• Volume [L, mL…]
• Concentrations [% strength, ratio, PPM]

Question 2

What does 1 Teaspoon equal in Milliliters?

Common Conversion

Answer 2

• 5 mL

Question 3

What does 1 Tablespoon equal in milliliters?

Common Conversion

Answer 3

• 15 mL

Question 4

What does 1 fl oz equal in Milliliters?

Common Conversion

Answer 4

• 30 mL

Question 5

What does 1 cup equal in both Ounces and Milliliters?

Common Conversion

Answer 5

• 8 oz
• 240 mL

Question 6

What does 1 pint equal in both Ounces and Milliliters?

Common Conversion

Answer 6

• 16 oz
• 480 mL

Question 7

What does 1 Quart equal in both Pints and Milliliters?

Common Conversion?

Answer 7

• 2 Pints
• 960 mL

Question 8

What does 1 Gallon equal in both Quarts and Milliliters?

Common Conversion

Answer 8

• 4 Quarts
• 3840 mL

Question 9

What does 1 Kilogram equal in Pounds?

Common Conversion

Answer 9

• 2.2 Pounds

Question 10

What does 1 Ounces equal in Grams?

Common Conversion

Answer 10

• 28.4 g

Question 11

What does 1 Pound equal in both Grams and Ounces?

Common Conversion

Answer 11

• 454 g
• 16 oz

Question 12

What does 1 grain equal in Milligrams?

Common Conversion

Answer 12

• 65 mg

Question 13

Example Questions:

A prescription reads: “take 2 tsp PO Q6H x 7 days”. How many milliliters must be dispensed to complete 7 days of therapy?

Answer 13

• 280 mL

Question 14

Example Question:

If 1 ounces = 30 mL, how many Milliliters of sterile water will remain after 50 mL are used from a 16 ounce bottle?

Answer 14

• 430 mL

Question 15

What is the most important thing to note about rounding during calculations?

Answer 15

• 5, 6, 7, 8, 9 = ROUND UP
• 0, 1, 2, 3, 4 = ROUND DOWN

Question 16

Example Question:

A pediatric patient is receiving 5.25 mL of a drug every 4 hours. How many Milliliters will need to be required for the entire day? Round to the nearest whole number.

Answer 16

• 32 mL

Question 17

Example Questions:

A patient requires 410.9 mg of a drug daily. The daily dose will be divided for BID administration. How many milligrams will the patient receive BID? Round to the nearest whole number?

Answer 17

• 205 mg BID

Question 18

Example Question:

Enoxaparin 56.5 mg was ordered for a patient. The hospital rounds enoxiparin doese to the nearest 10 mg. What dose should be dispensed?

Why?

Answer 18

• 60 mg
• Rounding the Tenth spot

Question 19

Example Question:

A patient is 5’2” tall. What is her height in centimeters? Round to the nearest whole number.

Answer 19

• 157 cm

Question 20

What are Prooptions and what is important to know about setting up the equation?

Answer 20

• Two Fractions that are set equal with one variable having a X in its spot
• The units for the numberator MUST match and the units for the Demonator mUST match [(1 Apple/2 Peach) = (X Apple/5 Peach)]

Question 21

What are Dimensonal Analysis and what is important to know about setting up this equation?

Answer 21

• What we were taught in school
• 1000 mg x (1g / 1000 mg) x ….

Question 22

Example Question:

A patient weights 176 pounds. What is the patients wieght in Kilograms

Work it both ways: Proportion and Dimensional Anaylsis

Answer 22

• 80 kg

Question 23

Example Questions:

How many Milliliters are in 5 liters?

Answer 23

• 5000 mL

Question 24

Example Question

How many Decliters are equal to 200 Milliliters

Answer 24

• 2 dL

Question 25

# Example Questions: How many **nanograms** are equal to **5 kg**?

Answer 25

- 5 trillion ng

Question 26

# Example Question: How many **grams** are equal to **50,000,000 Nanograms**?

Answer 26

- 0.05 g

Question 27

# Example Question: A pharmacist receives this prescription for hydrocondone/acetaminphen. how many **tablets** should be dispensed? ## Footnote **Hydrocodone/Actaminophen 5/325 mg #12 Sig: i-ii tabs PO q4-6h PRN pain x 2 days**

Answer 27

- 12 tablets - WRITTEN for 12

Question 28

# Example Question: How many **milliliters** of mylanta suspension are contained in each dose of the prescription below? Round to the nearest **whole number**? ## Footnote - Belladonna Tincture [10 mL] - Phenobarbital [60 mL] - Mylanta Susp. qs. ad [120 mL] - Sig: 5 ml BID

Answer 28

- 2 mL

Question 29

# Example Question A pharmacist receives a prescripton for **"Vigamox 0.5% Dispense 3 mL 1gtt TID OU x 7 days"**. How any **drops** will the patient used per day?

Answer 29

- 6 drops per day

Question 30

# Example Question A 7-year-old male child [**48 pounds**] presents to the urgent care clinic with a fever of 102 F and Nausea/Vomiting that started the previous day. He will revceive an **Acetaminophen 5 grain** suppository for the fever. A pharmacist receives a prescription for the suppository with the instructions: **use 1 PR Q4-6H PRN TEMP > 102 F**. How many **Milligrams per Kilogram** will the child receive per dose? Round to the nearest **whole number**.

Answer 30

- 15 mg/kg

Question 31

# Example Question A phamacist received the SMX/TMP prescription and dispensed **3 oz** to the patient. How many **days** of therapy will the patient be short? **Use 30 mL for 1 fl oz**. ## Footnote **SMX/TMP 200-5 mg/5ml sig: 1 tsp PO BID x 10 days, until all taken**

Answer 31

- 10 mL = 1 day

Question 32

# Example Question A pharmacist has tablets that contain **0.25 mg of levothyroxine** per tablet. The tablets will be crushed and mixed with glycerol and water to prepare a prescription for a child weighing **36 pounds**. How many **levothyroxine tablets** will be needed to compound the following prescription: ## Footnote - Levothyroxine Liq. (0.1 mg/ml) - Disp. (60 mL) - Sig: 0.01 mg per kg PO BID

Answer 32

- 24 tabs of Levothyroxine needed

Question 33

# Example Question How many **Milligrams** of codeine will be contained in **each capsule**? ## Footnote - Codeine Sulfate (0.6 g) - Guaifenesin (1.2 g) - Caffeine (0.15 g) - M. ft. caps. no 24 - Sig: One cap TID PRN cough

Answer 33

- 25 mg of codeine per capsule

Question 34

# Example Question: How many **grains** of aspirin will be contained in **each capsule**? Round to the nearest **tenth**. ## Footnote - Aspirin (6 g) - Phenacetin (3.2 g) - Caffeine (0.48 g) - M. ft. no. 20 caps - Sig: One cap Q8H PRN pain

Answer 34

- 4.6 grains/capsule

Question 35

# Example Question A **45 milliliter** nasal spray delivers **20 sprays per milliliters** of solution. Each spray contains **1.5 mg** of active drug. How many **milligrams** of drug are contain in the **45 mL** package?

Answer 35

- 1350 mg of active drug

Question 36

# Example Question A metered-dose inhaler provides **90 micrograms** of albuterol sulfate with each inhalation. The canister provides **200 inhalations**. If the patient uses the **entire canister**, how many **milligrams** will the patient have received?

Answer 36

- 18 mg

Question 37

# Example Question: **Digoxin** injection is supplied to in ampules of **500 mcg per 2 ml**. How many **milliliters** must a nurse administer to provide a dose of **0.2 mg**?

Answer 37

- 0.8 mL

Question 38

# Example Question If **one 10 mL vial** contains **0.05 g of diltiazem**, how many **milliliters** should be administered to provide a **25 mg** dose of diltiazem?

Answer 38

- 5 ml

Question 39

What are some of the **drug-dose** conversions that we **MUST** know for the NAPLEX ## Footnote Will go into more detail in the coresponding chapters

Answer 39

- Aminophylline/Theophylline [Asthma] - Calcuim Salts [Osteoporsis, Menopause, Testosterone; Calc IV] - Insulin [Diabetes] - Iron Salts [Anemia] - Lithium Salts [Bipolar Disorders; Calc II] - Loop Diuretics [HF] - Opiods [Pain] - Potassium Cholirde [HF; Calc II] - Statins [Dyslipidemia] - Steroids - IV:P conversions

Question 40

# Example Questions The Pharmacist is consulted to convert a patient form **prednisione 10 mg PO BID** to an equivalent dose of **Oral dexamethasone** given one daily. What is the equivalent daily dose? **Prednisione 5 mg = Dexamethasone 0.75mg**

Answer 40

- 3 mg of dexamethasone daily

Question 41

What is important to know about **ratios** in pharmacu calcutions?

Answer 41

- How ingredients should be mixed - X and Y mixed in 3:1 = 3 parts X and 1 part Y

Question 42

# Example Question How many **grams** fo bacitracin and nystatin are required to prepare **150 g of a 2:3** topical bacitracin:nystatin onitment?

Answer 42

- 60 g of Bacitracin - 90 g of Nystatin

Question 43

What is the way that we convert a **decimal to a precent** and a **precent to a decimal**?

Answer 43

- D to P = **MULTIPLE** by 100 - P to D = **DIVIDE** by 100

Question 44

# Example Question HT is a 16-year-old female who complains of weakness, fatigue, and heavy menstrul periods> She is diagnosed with anemia. HT takes **ferrous sulfate 220 mg** once daily. How many **milligrams** of elemental iron does HT receive form the supplement? **Ferrous Sulfate is 20% Elemtent Iron**

Answer 44

- 44 mg elemental iron

Question 45

# Example Question Calculate **3.5 squared**?

Answer 45

- 12.25

Question 46

# Example Question Calculate **2 to the power of 4**

Answer 46

- 16

Question 47

What dose **B-PEMDAS** mean withi the **Order of Operations**?

Answer 47

- **B**rackets - **P**arentheses - **E**xponents - **M**ultipy - **D**ivide - **A**dd - **S**ubtract ## Footnote Bruh, Please Excuse My Dear Aunt Sally

Question 48

# Example Question Sj is a famle patient in the internal medicine unit receiving treatment following a motor vehicle accident. Her medication includes **Lorazepam, Morphine & Phenytoin**. Her serum albumin is **1.8 g/dL** and her phenytoin level is **9.6 mcg/mL**. Her CrCl is **61 mL/min**. Calculate SJ's **Corrected Phenytoin** level (in mcg/mL) using the formula provided. Round to the nearest **one decimal place**.. ## Footnote Corrected Phenytoin = [(Total Phenytoin Measured)/((0.2 x Albumin) + 0.1))]

Answer 48

- 20.9 mcg/mL