Pharmacy Math and Calculations 1/2 +3/4 5/6+ 6/5 3 2/ /4 7/8 2/3 1/2 1/4 5 5/8 2 2/ ,

Transcription

1 Perform the necessary functions. Pharmacy Math and Calculations /2 +3/4 5/6+ 6/5 3 2/ /4 7/8 2/3 1/2 1/4 5 5/8 2 2/ , Solve for x 4x = 250 5x+6 = 2x +48 x =

2 Express each as a decimal 50% = 4/5 = 43/2 = 7/9 = 7/10 = 300/1000 = 1/10,000 = 3 2/3 = Solve 4% of % of 3 12% of % of 81 5% of % of 50 Round to the nearest whole number Round to the nearest tenth Convert the minutes to hours 20 min. 45 min. 50 min 30 min

3 Convert hours to nearest minute 0.5 hr 0.75 hr 0.66 hr 0.23 hr Write these decimals as a fraction Solve for x x -32 = 5(6 x 48) 2(x-3) (x +2) = 500 (x + 3) (x-3) ½ x = 5x + 10 Solve You have 4 oz of Benadryl elixir if you are asked to make 1:2 solution of Benadryl to Maalox how much Maalox should you use and what will the final volume be?

4 Convert the Following 425 mg to kg 5 ml to tsp 0.8 mg to g 30 ml to oz 380 lb to kg 4 oz to ml 3.28 kg to lb 2 L to ml 2.97 kg to g 3 tsp to ml 1.5L to ml 2 tbsp to ml 6.3 lb to kg 6 tbsp to oz 5lb 2 oz to kg 3 cc to ml 4 lb 1 oz to oz 50 ml to oz 20 ml to dl 497 ml to L Solve showing your work You need to make an IV with 40 meq of KCl; if you have a vial of KCl with a concentration of 2 meq /ml how many mls of KCl should you add to make the IV?

5 You need to make a Rocephin IV for a child. The dose is 350 mg, if you dilute a 500 mg vial of Rocephin to give a concentration of 100 mg/ml how many mls are needed for the dose? A patient is to get a dose of Gentamicin 5 mg/kg, if they weigh 150 lb. what it the dose of Gentamicin?(round to nearest 10 mg) If Gentamicin comes in a concentration of 40 mg/ml how many mls should they get? If you add the dose to a 100 ml bag of 0.5NS what is the final concentration? ER calls wanting Lovenox 1 mg/kg for a pt. who weights 280 lbs. If we dose to the nearest 10 mg what is the dose of Lovenox? You have a TPN order for 12 mmoles/liter of potassium phosphate. The TPN compounder requires that the potassium phosphate be entered in meq not mmoles. The bottle of potassium phosphate is labeled 3 mmoles/ml and 4.4 meq /ml. How many meq of potassium phosphate should be entered?

6 What does a patient weigh in kg if they weigh 398 lbs.? A patient needed Concerta 54 mg every morning. The hospital only has 27 mg tablets, how many should the patient take? You have an order for Pediapred 1-2 mg/kg bid for 5 days. Pediapred is 6.7mg/5ml what should the dose be in mg and ml for a child who weighs 30 lbs.? How many mls would be needed for the 5 days? (round to nearest ml) The doctor writes for a patient to have 2.5 mg of digoxin. Digoxin comes as 0.125mg and 0.25mg tablet, usual adult dose to 0.5mg daily. How many tablets for the dose? Is that a problem? You need to make an IV of Tobramycin 280 mg, if the concentration is 40mg/ml how many mls of Tobramycin do you need to add to the bag of ½ NS for the dose?

7 You have an order for a dose of 23.8 mg of a drug that comes in a concentration of 2.5 mg/ml how many mls do you need for the dose? How many grams of boric acid are required to prepare 250 ml of 5 % (w/v) solution? There is an order for zinc oxide cream and nystatin cream in a 4:1 ratio. How many grams of each will be needed for make 100 grams? If you use 15 ml of vancomycin 50mg/ ml to make an IV piggy back, what is the dose? If the solution bag has 500mls what is the final concentration?

8 There is an order for a baby to receive 4 mg/kg of Gentamicin. The baby weighs 2859 g. How many mg of Gentamicin should you use?(round to nearest mg) If the concentration of Gentamicin is 10 mg/ml and you are to have a total final volume of 3 ml how many mls of Gentamicin and mls of ½ NS will you use? A vial of 20,000,000 units of penicillin g is diluted with 50 ml of NS. How many units in 1ml? How many mls are needed for a dose of 4,000,000 units? You have an order for prednisone 40 mg bid 2 day, then Prednisone 30 mg bid 2 days, then 20 mg bid 2 day, then 10 mg bid 2days, then 10 mg daily 2 days, and then stop. If you only use 10 mg tablets how many will be needed? How many mls of a 50% dextrose solution do you needed for a 25 g dose?

9 How many meq of sodium bicarbonate in 150 ml if it comes 8.4%, 50mEq/ 50ml? You have an order for paclitaxel 270 mg, if it comes in a concentration of 6 mg/ml how many mls are needed for the dose? You needed to make an epidural fentanyl 2 mcg/ml in 0.2% ropivicaine 100 ml. How many mcg of fentanyl do you need? If fentanyl is 100mcg/ml how many mls of fentanyl do you need? You need to batch 5 fentanyl PCAs; if each contains 300mcg of fentanyl how many mls of fentanyl will you use? (fentanyl 100mcg/2ml)

10 Fill in the following chart Drug Maximum concentration Dose Minimum Volume Vancomycin 5mg/ml 1750 mg Ampicillin 100mg/ml 280 mg Acyclovir 7mg/ml 750 mg Claforan 100mg/ml 118 mg Rocephin 40mg/ml 750 mg Convert to military time 3:15 am 15:30 pm 5:00 pm midnight 10:00 am 8:45 pm Convert from military time to regular time

11 HELPFUL INFORMATION Roman Numerals ss =1/2 L or l = 50 I or I =1 C or c = 100 V or v = 5 D of d = 500 X or x = 10 M or m = 1000 A List of the Metric Prefixes Multiplier Prefix Symbol Numerical Exponential yotta Y 1,000,000,000,000,000,000,000, zetta Z 1,000,000,000,000,000,000, exa E 1,000,000,000,000,000, peta P 1,000,000,000,000, tera T 1,000,000,000, giga G 1,000,000, mega M 1,000, kilo k 1, hecto h deca da no prefix means: deci d centi c milli m micro nano n pico p femto f atto a zepto z yocto y

12 Measurement Conversion Tables Approximate Measures: Liquids 1 fl oz = 30 ml 1 cup (8 fl oz) = 240 ml 1 pint (16 fl oz) = 480 ml 1 quart (32 fl oz) = 960 ml 1 gallon (128 fl oz) = 3800 ml 1 teaspoon = 5 ml 1 tablespoon = 15 ml Approximate Measures: Weights 1 oz = 30 g 1 lb (16 oz) = 480 g 15 grains = 1 g 1 grain = 60 mg Apothecary Equivalents: Weight 1 scruple = 20 grains (gr) 60 grains = 1 dram 8 drams = 1 ounce 1 ounce = 480 grains 16 ounces = 1 pound (lb) Exact Equivalents 1 g = grains 1 grain = 64.8 mg 1 ml = minims 1 Minim = 0.06 ml 1 oz = g 1 lb = g ( kg) 1 kg = 2.2 lb 1 fluid oz (fl oz) = ml 1 pint (pt) = ml 1 quart (qt) = ml 0.1 mg = 1/600 grain (gr) 0.12 mg = 1/500 gr 0.15 mg = 1/400 gr 0.2 mg = 1/300 gr 0.3 mg = 1/200 gr 0.4 mg = 1/150 gr 0.5 mg = 1/120 gr 0.6 mg = 1/100 gr 0.8 mg = 1/80 gr 1 mg = 1/65 gr 1 kg = 1000 g 1 g = 1000 mg 1 mg = 1000 mg Apothecary Equivalents: Volume 60 minims = 1 fluidram 8 fluidrams = 1 fluid ounce 1 fluid ounce = 480 minims 16 fluid ounces = 1 pint (pt)

13 TEMPERATURE 1 C degree = 1.8 F degrees 1 F degree = 5/9 C degrees Fahrenheit to Centigrade or Celsius: ( F 32) X 5/9 = C Centigrade or Celsius to Fahrenheit: ( C X 9/5) + 32 = F Measurement Equivalents 1 tablespoon (tbsp) = 3 teaspoons (tsp) 1 cup = 48 teaspoons 1 cup= 16 tablespoons 8 fluid ounces (fl oz) = 1 cup 1 pint (pt) = 2 cups 1 quart (qt) = 2 pints 4 cups = 1 quart 1 gallon (gal) = 4 quarts 16 ounces (oz) = 1 pound (lb) 1 milliliter (ml) = 1 cubic centimeter (cc) 1 inch (in) = 2.54 centimeters (cm) English-Metric Measurement Conversions Equivalent Metric-English Measures UNIT ENGLISH to METRIC METRIC to ENGLISH Length Volume Weight 1 mile = 1.61 kilometers 1 yard = meter 1 foot = meter 1 inch = 2.54 centimeters 1 gallon = 3.79 liters 1 quart = liter 1 pound = kilogram 1 ounce = grams 1 kilometer =.62 mile 1 meter = 1.09 yard 1 meter = 3.28 feet 1 centimeter = in 1 liter = gallon 1 liter = 1.06 quarts 1 kilogram = 2.2 pounds 1 gram = ounce

14 The following table summarizes the relationship between regular and military time. Regular Time Military Time Regular Time Military Time Midnight 0000 Noon :00 a.m :00 p.m :00 a.m :00 p.m :00 a.m :00 p.m :00 a.m :00 p.m :00 a.m :00 p.m :00 a.m :00 p.m :00 a.m :00 p.m :00 a.m :00 p.m :00 a.m :00 p.m :00 a.m :00 p.m. 11:00 a.m :00 p.m Concentration Expressed as a Percentage (w/w) Percent weight-in-weight (w/w) is the grams of a drug in 100 grams of the product. 10% (W/W) NaCL in 100 grams of solution contains 10 grams NaCl (w/v) Percent weight-in-volume (w/v) is the grams of a drug in 100 ml of the product. 10% (W/V) NaCl in 100 ml of solution contains 10 grams NaCl (v/v) Percent volume-in-volume (v/v) is the milliliters of the drug in 100 ml of the product. 10% (V/V) wintergreen oil in 100 ml of alcohol contains 10 ml of wintergreen oil