2. Abbreviations Review acceptable and non-acceptable abbreviations Pharmacology book Fundamentals book Kee & Marshall Inside front cover Chapter 3, pg. 68-70
3. Rounding NOTE: Don’t round until you have completely finished the problem Rounding within the problem will result in a close answer, but not an exact one
4. Rounding To round to the nearest tenth, carry out the division process to hundredths place (2 positions to the right of the decimal) 3/8 = 0.37 1/3 = 0.33 3/4 = 0.75
5. Rounding Next, look at the number in the hundredths place If the number is less than 5, then round down 0.33 rounds to 0.3 If the number is 5 or higher, then round up, 0.75 rounds to 0.8 0.37 rounds to 0.4
6. Volume and Concentration Meds are given to clients in some type of volume (ml, tablets, capsules, mEq, units, etc.) Concentration indicates the amount of medication in a given amount of solution (mg/ml, units/ml, mg/tablet, etc.)
7. Conversions Remember a conversion = 1 It can be used in an equation with either number as the numerator or denominator The unit of measure is BEFORE THE NUMBER in the apothecary system The unit of measure is AFTER THE NUMBER in the metric and household systems
8. Common Metric Conversions Metric: 1 kg = 2.2 pounds (#) 1 kg = 1000 g 1 mg = 1000 mcg 1 g = 100 mg 2.54 cm = 1 inch
9. Other Common Conversions Apothecary: 1 grain = 60 mg Remember ss = ½ grain Household: 1 teaspoon = 5 ml 30 ml = 1 ounce 3 teaspoons = 1 tablespoon
10. Basic Formula D x V = amount to be given H 1 D = desired dose (what client is supposed to receive) H = dosage you have on hand V = volume or vehicle that the dosage on hand is in ‘D’ and ‘H’ must be in the same unit of measurement
11. Setting up Problems Use the label factoring method (dimensional analysis – DA). This method uses labels with the numbers to arrive at the correct answer (Kee pg. 92- 104) Determine unit of measurement for answer Set up problem until labels cancel out and you are left with correct label for the answer
12. Dosages based on Weight Drugs may be ordered based on the weight of the client (amount of mg of the drug per kg of weight) When converting weight in pounds to weight in kilograms, the number is approximately less than ½ of the weight in pounds 110 # = 50 kg; 220# = 100 kg; 140# = 63.6 kg
13. Divided Doses You may have a problem that asks you to calculate the entire amount of drug that is to be given in a 24 hour period A problem may give you the amount of drug the client is to receive in 24 hours and ask you to calculate an individual dose
14. Reconstitution of a Drug A problem might give you a great deal of information about reconstituting a drug – how much diluent, vial size, etc. (Kee pg. 186) The bottom line is to recognize the final concentration Order for 1.5 g of penicillin IM q6h. The pharmacy sends a vial labeled penicillin 5 g/vial in dry form. Reconstitute with 5.6 ml of sterile water to yield 1000 mg/ml. How much should be given?
15. Hints for Taking Quizzes Read the directions completely Decide the unit of measure needed for the correct answer Read the problem again after you decide on the answer. Is the answer logical? Check calculations more than once on calculator Read the directions again