Math and Dosage Calculations for Health Care 3rd Edition by James Whaley, Kathryn Booth, Booth Kathryn

Exercise 70

In Exercises 19, determine if the dosage ordered is safe. If the order is safe, then find the amount to administer. Assume that the patients have impaired renal functions.
The patient: 85-year-old male, 6 ft 1 in. tall, 210 lb, CL CR of 64 mL/min. Ideal weight should be 195 lb.
Ordered: Cartrol 2.5 mg po q24h
On hand: Cartrol 2.5 mg/tablet
According to the package insert, the usual dosage interval for 2.5 mg is as follows: for patients with creatinine clearance above 60 mL/min, 24 h; for 20 to 60 mL/min, 48 h; and for less than 20 mL/min, 72 h.