A) A prescription requires the preparation of 2 g suppositories. Each one contains 20 mg of morphine sulphate and 200 mg of aspirin in theobroma oil base. Calculate the amount of each ingredient for 20 suppositories. The displacement values are: 1.6 for morphine sulphate and 1.1 for aspirin. Mould calibration is 1.05. (4 marks)
B) How many millimoles/L of chloride ion are contained in 1 litre of Potassium Chloride and Sodium Chloride infusion BP (the infusion fluid contains: potassium chloride 0.3%; sodium chloride 0.9%, molecular weight of potassium is 39, chloride is 35.5, and sodium is 23)? (3 marks)
C) A vial of a drug is labelled “10,000 units: to reconstitute, add 17 mL of sterile water for injection to obtain 500 units per ml”. How many mL of water must a pharmacist add if a 1000 units/mL concentration is needed? (3 marks)
D) Patient presents with pulmonary embolism (PE) with pre-existing poor and unstable renal function. Doctor prescribed unfractionated heparin (UFH) standard dose per protocol. Your hospital's UFH protocol for PE calls for 80 units/kg IV bolus (max 10,000 units), followed by continuous infusion of 18 units/kg/hour (max 1,800 units/hr). Patient weighs 206 lbs.
i) Your hospital stocks UFH for injection in 10,000 units in 2 ml vials. What is the dose to be administered for the bolus dose?
ii) Per your hospital's UFH protocol, UFH is to be diluted to 100 units/mL, in 250 ml bags for IV continuous infusion. You prepare two bags of UFH for IV infusion for the daily supply. How much volume of UFH stock solution is needed to prepare each bag of UFH for continuous infusion?
iii) What is the appropriate initial infusion rate, in mL/h?
E) Patient presents with a cerebral oedema so HYPERTONIC saline (sodium chloride 3% solution) intravenous infusion is prescribed. You have CONCENTRATED sodium chloride (“NaCl“) 23.4% (w/v) solution (30 mL/vial) for injection and normal saline (sodium chloride 0.9% for injection). Molecular weight of NaCl is 58.44 g/mol.
i) You are asked to prepare a 500 mL bag of HYPERTONIC saline for infusion, by diluting the CONCENTRATED NaCl solution with normal saline. For the bag, how much CONCENTRATED NaCl solution and normal saline is required respectively, in mL?
ii) What is the approximate osmolarity of the HYPERTONIC 3% NaCl solution in mOsmol/L?
F) Patient has congestive heart failure and is taking digoxin tablets. The patient is a 72 year old male, weighs 64 kg, he is 168 cm tall and his latest serum creatinine is 86 micromol per litre. The formulas to estimate digoxin's volume of distribution (Vd) and clearance(Cl) are listed below.
Vd (L) = (3.8 L/kilogram)*(Weight in kg) + (3.1 L/ mL/min)*(CrCl in mL/min)
CL (mL/min) = (0.33 mL/kg/min)*(Weight in kg) + 0.9*(CrCL in mL/min)
(Note: CrCl stands for creatinine clearance estimated by the Cockroft-Gault equation)
i) What is the expected steady-state plasma half life in hours?
ii) Patient is taking digoxin capsules 0.125 mg orally every other day. The expected bioavailability of the capsule is 95%. What is the expected steady-state average plasma digoxin concentration, in mcg/L?
G) A lady presents a prescription for morphine oral solution 0.3 mg/kg/dose Q4H around-the-clock for three days, for post-operative pain. Your pharmacy stocks morphine sulfate 10 mg/5 mL and 50 mg/5 mL alcohol-free oral solutions.
i) The prescription is for her 4 kg infant. Your pharmacy has 1 mL insulin syringes (calibration marks 0.01), and 3 mL oral syringes (calibration marks of 0.1 mL). What is an appropriate volume to be taken for each dose?
ii) What is the total volume to be dispensed?