a) An infant (body weight 2.4 kg) is prescribed total parenteral nutrition. The parenteral nutrition formula contains 55 ml of dextrose 10% in a total volume of 550ml to be infused over 24 hours. (molecular weight of dextrose = 180)

What is the rate of dextrose infusion (in mg/kg/min)? (3 marks)

b) How many millilitres of 85% (w/w) phosphoric acid having a density of 1.71 g/ml should be used in preparing 3.8L of 0.25% (w/v) phosphoric acid solution to be used for bladder irrigation? (3 marks)

c) A child (body weight 60lbs) required a dose of 8 mg/kg of ampicillin. Given that a 5 ml dose is to be given, what volume of water must be added when the powder is reconstituted? Instruction on the label indicates that dilution to 150 ml (by adding 111 ml) gives 250 mg ampicillin per 5 ml. (4 marks)

d) The desired steady-state concentration of drug X is 5 mg/L. Clearance of drug X is 30 L/h and its volume of distribution is 150L.

i) What infusion rate will be necessary to reach the target concentration? 2 marks

ii) How long will it take to reach steady state? 2 marks

iii) What loading dose will be required to instantaneously achieve steady state? 2 marks

e) You are asked to prepare 30 ml of an eye drop with the following formula (4 marks)

Phenacaine hydrochloride              1%

Oxytetracycline hydrochloride       15mL

Boric acid                                          qs

Purified water                                  30 mL

Make isotonic solution

The 1% solution of oxytetracycline hydrochloride is already isotonic.

How many grams of boric acid should be used in compounding the above eye drop? (sodium chloride equivalent of phenacaine hydrochloride = 0.2, oxytetracycline hydrochloride = 0.12, boric acid = 0.52)