Pharmaceutical Calculations 2

Get our new Pharmacy Calculations book here: http://www.lulu.com/shop/pharmacy-cpa/the-ultimate-pharmacy-calculations-guide/paperback/product-21648531.html GPhC Exam Question Blog http://gphcexam.pharmacycpa.com/ Facebook Group https://www.facebook.com/groups/13009... Free online GPhC Exam Questions http://pharmacycpa.com/login/index.php 20 Calculation Questions in 20 minutes From Pharmacycpa.com 1. Mr Green, a 50 year old man weighing 70 kg, requires an oral loading dose of digoxin. Which one of the following should be suggested to aim for a plasma concentration of 1.5 micrograms/litre? You are given that the Volume of Distribution, Vd, per kg body weight is 6 litres; the Salt Factor S = 1; the Bioavailability F= 0.7; and the formula, where Cp is the Target Plasma Concentration: Loading dose = (VdxCp) / (SxF) A A total dose of 1200 micrograms in four divided doses B A total dose of 500 mcg as stat dose C total dose of 900 mcg as stat dose D total dose of 500mcg in two divided doses E total dose of 900 mcg as tds. 2. A patient is admitted to hospital following an overdose ofkuroxacillin. The drug's half-life is 8.5 hours. A toxic plasma concentration of 52 microgram/mL is measured. How long, in hours, will it take for the plasma concentration to fall to 3.25 microgram/mL? (You may assume that the absorption and distribution is complete and the elimination is described by a I st order process.) A 10 B 23 C 34 D 42 E 50 3. A pharmacist is required to send 100 mL of an aqueous solution of chlorhexidine gluconate which when diluted 1 in 10 produces a 1 in 1000 solution. The pharmacist has available an aqueous stock solution of 20% w/v chlorhexidine gluconate. The correct formula will be A chlorhexidine gluconate concentrate 1 mL, water to 100 mL B chlorhexidine gluconate concentrate 2 mL, water to 100 mL C chlorhexidine gluconate concentrate 5 mL, water to 100 mL D chlorhexidine gluconate concentrate 10 mL, water to 100 mL E chlorhexidine gluconate concentrate 20 mL, water to 100 mL C - 1 in 1000 = 0.1 in 100, ie 0.1 % w/v So concentration of solution to be made is 10 x this, ie 1% So pharmacist must dilute the concentrate (20%) by a factor of 20 So s/he needs 5 ml of concentrate to 100ml of final product 5ml water to 100ml. 5ml of 20% contains 0.2 x 5 = 1g 4. How much potassium permanganate would be needed in order to prepare 500 mL of a 1 in 200 solution? A 200 mg B 500 mg C 1 g D 2.5 g E 5g 5. You are required to prepare 10 powders each weighing 200 mg and containing 5 mg of a drug. The only form of the drug that is available is 30 mg tablets. You will require A two tablets made up to 1.2 g with lactose = 60mg in 1200 B two tabs made up to 2.0g with lactose = 60 in 2000 = C two tablets made up to 2.4 g with lactose = 60 in 2400 = 0.025 D two tablets made up to 3.0 g with lactose = 60 in 3000 = 0.02 E one tablet made up to 2.4 g with lactose = 30 in 2400 = 0.0125 10 x 200 overall weight is 2g 10 x 5 active = 50mg in 2000 = 0.025 60mg in 2400mg = 0.025 60mg in 3000mg = 0.02 6. Which one of the following is the usual dose of oral salbutamol to recommend for a one year old child of average weight for his/her age? A 2.5 mg q.d.s. B 2.0 mg q.d.s. C 1.5 mg q.d.s. D. 1.0 mg q.d.s. E 0.5 mg q.d.s. 7. The ward pharmacist is asked what volume of Potassium Chloride Solution, Strong should be added to a 500 mL bag of sodium chloride 0.9% infusion to produce a concentration of 12 mmol of potassium per L (MR potassium chloride =75). The volume of Potassium Chloride Solution, Strong required is A 0.6 ml B 1.2 ml C 1.8 ml D 2.4 ml E 3.0ml The following questions concern the following quantities of Sodium Bicarb A 0.15 g B 1.5 g C 15 g D 150 g E 1500g Select the correct quantity when preparing... 8. 300 mL of Aromatic Magnesium Carbonate mixture, BP 9. 6 kg of Magnesium Trisi1icate oral powder, compound, BP 10. 3 L of Kaolin and Morphine mixture, BP