Pharmaceutical Calculations

Q: A 250-mL infusion bottle contains 5.86 g of potassium chloride (KCl). How many milliequivalents (mEq) of KCl are present? (Mol.wt. KCl =74.6)

(a) :  12.7mEq
(b) :  20 mEq
(c) :  78.5 mEq
(d) :  150 mEq
(e) :  157 mEq
Answer:  78.5 mEq
Explanation:   1 equivalent weight of KCl = 74.6 g, therefore, 1 milliequivalent (mEq) = 74.6 mg 1 mEg x mEg 74.6 mg 5860 mg x= 78.5 mEq fh. 1- (mEg) (mol. wt.) mg 0 c emlCa - (valence) Or the problem may be solved by using the equation (23:159) 5860 = (x) (74.6) mg (1) x= 78.5 mg

Q: The adult dose of a drug is 250 mg. What would be the approximate dose for a 6-year-old child weighing 60 lb? (Use Young's Rule.)

(a) :  60 mg
(b) :  85 mg
(c) :  100 mg
(d) :  125 mg
(e) :  180 mg
Answer:  85 mg
Explanation:  Young's Rule relates a child's dose to the child's age. Age (yr) x Adult dose (Age [yr] + 12) 6 (6 + 12) x 250 mg Dose = 83.3 or 85 mg Child's dose = Child's dose = Although well intended, rules like Young's (child's age), Cowling's (age at next birthday divided by 24), Clark's (weight divided by average weight of an adult [150 lb]) are only rough estimates. Pharmacists should check the literature for individual drug dosing for children. In some instances, the child's dose will be similar to th

Q: A hospital clinic requests 2 lb of 2% hydrocortisone ointment. How many grams of 5% hydrocortisone ointment could be diluted with white petrolatum to prepare this order?

(a) :  18.2 g
(b) :  27.5 g
(c) :  45.4 g
(d) :  363 g
(e) :  545 g
Answer:  363 g
Explanation:   Two pounds would contain 454 x2= 908g of ointment. The final preparation would contain 908 gx 2% = 18.18 g of pure hydro-cortisone. Because the available hydrocorti- sone ointment is 5% strength, one would need ~-~ 100 g- x g x = 363.2 g of the 5% ointment Or, using the equation (Ql) (C1) = (Qz) (Cz) (908 g) (2% WjW) = (x g) (5% WjW) x = 363.2 g

Q: One hundred (100) micrograms equals I. 100,000 nanograms II. 0.1 milligrams III. 0.001 grams

(a) :  I only
(b) :  III only
(c) :  I and II only
(d) :  II and III only
(e) :  I, II, and III
Answer:  I and II only
Explanation:  1 mg 1g_ 100 mcg x 1000 mcg x 1000 mg - 0.0001 g In this example, consider one microgram as equaling 1000 nanograms; thus, 100 mcg = 100,000 ng. Since 1 milligram equals 1000 mcg, 100 mcg equals 0.1 mg. If 1 mg equals .001 gram, 0.1 mg or 100 mcg equals 0.0001 g. It may be clearer if one solves this conversion using di- mensional analysis.

Register now to view all Question's

Sign in OR Sign Up


Back to top