Mock Paper 1 Flashcards
(22 cards)
Mrs A is being treated in the infectious-diseases unit for hospital-acquired pneumonia. The consultant wants to switch her to a high-dose continuous meropenem infusion because her creatinine clearance is > 120 mL min−1. Pharmacy protocol states the full 24-h dose of 2 g must be dissolved in sufficient diluent so that the final concentration is 0.08 mol L−1 to reduce line occlusion. Meropenem powder has a molecular weight of 383 g mol−1 and comes in 1 g vials. Nurses use standard 1-litre elastomeric pumps.
Calculate the total volume, in mL, of infusion solution required to achieve the 0.08 mol L−1 concentration. Give your answer to the nearest whole number.
65ml
2g/383g/mol = 0.0052219mol
0.0052219ml x L/0.08 = 0.0652737L
65ml
Your 45-bed orthopaedic ward uses cefuroxime surgical prophylaxis at 3 g day for 5 days per patient. Current stock is 750 mg vials costing £2.40 each; whole vials must be used (no sharing). A manufacturer offers 1.5 g vials at £3.95 each; again, whole vials only. An audit shows 120 orthopaedic patients start prophylaxis every month. The medicines optimisation team asks you to model the financial impact before approving the switch
Calculate the monthly saving, in £, if the ward changes to the 1.5 g vials. Give your answer to the nearest pound.
1020
3000/750 = 4 vials
4 x 2.4 x 5 x 120 = 5760
3000/1500 = 2 vials
2 x 3.95 x 5 x 120 = 4740
5760 - 4740 = 1020
A patient on the OPAT service needs a single 400 mg dose of teicoplanin for home administration. Teicoplanin is supplied only as 200 mg powder vials with a displacement volume of 0.28 mL per vial. Each vial is routinely reconstituted with 3 mL of water for injection.
For safety, the entire contents of two reconstituted vials are drawn into one syringe before any further dilution.
Calculate the total volume, in mL, that will be drawn into the syringe from the two reconstituted vials. Give your answer to two decimal places.
6.56ml
3 + 0.28 = 3.28 x 2 = 6.56
You have been asked to produce 350ml of a concentrated sulphuric acid, such that 7.5ml of this solution diluted to 1.5L would produce a 0.04% w/v solution.
What weight of sulphuric acid, in grams, is required for the concentrated solution?
28g
1500ml/ 7.5ml = 200 times
0.04% x 200 = 8%
8g in 100ml = 28g in 350ml
Surgical spirit contains 2.5% castor oil, 2% diethyl phthalate, 95%industrial methylated spirit, and 0.5% methyl salicylate. Diethyl phthalate 99% concentrate is used to produce surgical spirit.
What volume of diethyl phthalate 99% concentrate, in mL, is required to produce a batch of one thousand 200 mL bottles of surgical spirit?
Give your answer to the nearest whole number.
4040ml
200nl x 1000 = 20000ml
2ml in 100ml = 4000ml in 20000ml
99% concentrated = 100/99 = 1.01
4000ml x 1.01 = 4040ml
A 75kg man is to receive a loading dose of intravenous phenytoin. The loading dose is 20mg/kg (max 2g) given at a rate not exceeding 1mg/kg/minute (max 50mg per minute).
What is the minimum number of minutes over which his loading dose of phenytoin should be infused
Units = minute(s)
30mins
20mg x 75kg = 1500mg1500mg ÷ 50mg = 30mins
A 7-month-old girl weighs 7.3kg. She is being treated with meropenem 20mg/kg IV injection three times daily for urosepsis caused by Escherichia coli.Each 500mg vial of meropenem is reconstituted with 9.5mL Water for Injections BP. The displacement value for the 500mg vial is 0.5mL.
How many mL of the reconstituted injection are required for each dose? Give your answer to one decimal place.Units = mL
2.9ml
7.3kg x 20mg = 146mg/dose
9.5mL + 0.5mL = 10mL
500mg in 10mL = 50mg/mL146mg/50mg = 2.92mL = 2.9mL
Full amount of reconsitituted injection
You are a pharmacist working in a GP practice. A 59-year-old woman is on gliclazide 120mg modified release ONCE daily.BNF 87: ‘Dose equivalence and conversion: gliclazide modified release 30mg may be considered to be approximately equivalent in therapeutic effect to standard formulation gliclazide 80mg tablets.
Drug Cost
Gliclazide 30mg modified release tablets (28 tablets)£4.50
Gliclazide 80mg tablets (60 tablets)£1.50
If she were switched to standard release tablets, what would be the cost saving for 28-day treatment? Round your answer up to the
nearest pound.
Units = £
16 [ROUND UP]
1 day treatment = gliclazide 4 x 30mg m/r or 4 x 80mg standard release
28-day cost:
A, gliclazide 120mg m/r = £ 0.64 per day
0.64 x 28 = £17.92 for 28-day treatment
B, gliclazide 320mg standard tablets = £ 0.10 per day
(NB: standard release usually given as split dose e.g. 160mg BD)
0.10 x 28 = £2.80 for 28-day treatment
Cost saving: £17.92 - £2.80 = £15.12 = £16
A 36-year-old man on your ward has been prescribed sodium chloride infusion 0.9% w/v for electrolyte replacement. RMM of NaCl is 58.5
The junior doctor on the ward asks you how many mmol of sodium chloride are contained in a 2-litre bag of the 0.9%w/v solution.
Give your answer to the nearest 5 mmol
Units = mmol
310 mmol
ans: 307.692 [round to nearest 5, 308 ~ 310]
A 12-year-old child weighing 36kg is admitted to the accident and emergency department at the local hospital with acute adrenocortical insufficiency. The child is prescribed hydrocortisone by the consultant at a dose of 5mg/kg immediately and then repeated every six hours.
How many grams of hydrocortisone will the child receive in the first 20 hours? Give your answer to two decimal places.
Units = g
0.72g
Don’t forget the start dose (so multiple by 4)
A 50-year-old woman was admitted to your ward 3 days ago with an infective exacerbation of COPD. She was prescribed prednisolone 40mg once dailyalongside empirical antibiotic treatment. You receive her discharge letter and note the patient has been placed on a reducing dose of prednisolone. She has taken her dose already today and is now being discharged and advised to take 40mg for two more days. She should then reduce her dose by 5 mg every three days until she has stopped.
How many 5mg prednisolone tablets which the patient require to complete the reducing course?
Units = tablets
100
already taken 1 day (dont count that in)
You are working in a GP Practice and are looking at making cost savings across the regularly used drugs.
You notice that Movicol sachets cost £9.89 for 30 but Cosmocol sachets cost £4.10 for 30.
Your practice currently has 60 patients who are prescribed 60 Movicol sachets and 30 who are prescribed 30 Movicol sachets per 30 days.
1 month = 30 days
What is the expected cost saving, for all the patients at the practice over 180 days by undertaking a switch to Cosmocol? Give your answer to the nearest £5
Units = £
870
Step 1- Calculate cost saving per box
Movicol £9.89 – Cosmocol £4.10 = £5.79 saved per box
Step 2- Calculate cost saved for 180 days
180/30 = 6 cycles
Step 3- Calculate cost saved
30 x £5.79 = £173.760 x (£5.79 x 2 = £11.58) = £694.8
Add together £868.5
Round to nearest £5£870
You are working as a ICB pharmacist looking after two practices and have been asked to help the practices reduce expenditure on medicines.As a result, you are reviewing the use of ibuprofen 200mg orodispersible tablets, as these costs more than ibuprofen 200mg tablets at the equivalent dose of two tablets TDS.
Ibuprofen 200mg orodispersable
tablets sugar 219p/12
Ibuprofen 200mg tablets 326p/84
You have reviewed five patients from Practice A and eight patients from Practice B who are prescribed ibuprofen 200mg orodispersable tablets daily on repeat prescription. The practice has a repeat prescribing policy of 28 days treatment on a prescription.
What is the total saving for both practices for three repeats if 80% of suitable patients from Practice A and 50% of suitable patients from Practice B switch to using the ibuprofen 200mg tablets? Give your answer to the nearest twenty-five pounds.
Units = £
575
80% of A = 4
50% of B = 4
total of 8
219/12 - 326/84 = 0.1436905 pounds
0.143 x 8 x 28x 2 x 3 x 3 = 579 pounds
nearest 25 = 575
A newly qualified nurse asks for your advice on reconstituting a 2.25g vial of piperacillin/tazobactam (2g/0.25g). She is to reconstitute one vial to 10 mL using water for injection, and then add 1mL of this solution to a total final volume of 100mL with glucose 5%.
What is the concentration of the piperacillin component of this product in the infusion solution in mg/mL?
Units = mg/mL
2mg/ml
Question only asks about piperacillin
A 32-year-old woman is prescribed intravenous calcium gluconate to manage acute hypocalcaemia. The protocol advises administering 10 mmol of calcium as an IV infusion. The pharmacy stocks calcium gluconate 10 % solution, where each 10 mL ampoule contains 2.2 mmol of calcium ions.
Only whole ampoules can be used; partial ampoules are not permitted.
Calculate the total volume, in mL, of calcium gluconate 10 % solution required to deliver 10 mmol of calcium. Give your answer as a whole number.
50ml
Step 1 – Set up proportion
Each ampoule (10 mL) contains 2.2 mmol.
Find how many ampoules needed for 10 mmol:
10 / 2.2 = 4.545 ampoules
Step 2 – Round up (whole ampoules only)
Cannot use a partial ampoule, so round up to 5 ampoules
Step 3 –
Calculate total volume
5 x 10 = 50 mL
A 72-year-old man with cardiogenic shock is prescribed a continuous infusion of dobutamine. The target final concentration is 2,000 micrograms/mL in a 500 mL bag of glucose 5 %. The pharmacy stock available is dobutamine 50 mg/10 mL vials, with a displacement volume of 2 mL once diluted.
The final prepared bag must remain exactly 500 mL after adding the drug; no partial vials may be used, and no fluid may be discarded after injection (you may withdraw glucose before drug addition).
Calculate the number of full vials of dobutamine required to prepare the 500 mL bag. Give your answer as a whole number.
20 vials
Step 1 – Convert target concentration to mg/mL
2,000 micrograms/mL = 2 mg/mL (divide by 1000)
Step 2 – Calculate total amount of dobutamine needed
Target concentration = 2 mg/mL
Final bag volume = 500 mL
To find the total amount of drug needed, multiply the required concentration by the total volume:
2 x 500 = 1000mg
Each millilitre must contain 2 mg, and the bag contains 500 mL in total, therefore, 1000 mg of dobutamine is needed.
Step 3 – Calculate number of vials needed
1000mg / 50mg = 20 vials
20 vials
The respiratory ward is reviewing its inhaler stock to optimise both clinical outcomes and cost. Currently, the ward dispenses beclometasone 100 micrograms inhalers costing £4.20 each, delivering 200 doses per inhaler. A new beclometasone 200 micrograms inhaler is proposed, priced at £5.80 each, delivering 120 doses per inhaler. Patients are prescribed 400 micrograms twice daily.
You are asked to calculate the monthly cost difference per patient between using the current inhaler and the new inhaler, assuming each patient uses the correct number of inhalers needed per month.
Calculate the 30-day cost difference per patient between the two inhaler options. Give your final answer to the nearest pound.
3 pounds
Step 1 – Calculate daily dose requirement
400 x 2 = 800 micrograms per day
Step 2 – Work out doses needed per month
800mcg x 30 = 24,000 micrograms per month
Step 3 – Calculate how many inhalers needed for 100 microgram strength
200 doses x 100mcg = 20,000 micrograms per inhaler
Monthly inhaler requirement = 24,000 / 20,000 = 1.2 inhalers
Thus, each patient needs 2 inhalers per month (you cannot dispense part of an inhaler).
2 x £4.20 = £8.40 per month
Step 4 – Calculate how many inhalers needed for 200 microgram strength
120 doses x 200mcg = 24,000 micrograms per inhaler 1 inhaler covers the full monthly requirement exactly. 1 x £5.80 = £5.80 per month
2025 – PharmX Calculations Mock Exam Answers
Step 5 – Calculate cost difference
£8.40 - £5.80 = £2.60 saving
£3 saved per patient rounded to the nearest pound
A 52-year-old woman is admitted to the high-dependency unit following severe COPD exacerbation. She is started on a continuous intravenous aminophylline infusion at a rate of 65 mg/hour.
After 72 hours, her steady-state theophylline plasma concentration is measured at 11 micrograms/mL. Her weight is 68 kg, and she has normal liver and renal function.
You are informed that the average theophylline clearance (Cl) is 0.04 L/hr/kg.
Using this information, calculate her theophylline clearance in litres per hour (L/hour). Give your answer to one decimal place.
2.72 L/hr
0.04 x 68 = 2.72 L/hour
2.7 L/hour rounded to one decimal place
A specialist prescriber has started a 32-year-old patient on agomelatine to treat their depression. This medicine is to be taken at bedtime and has an elimination half-life of 1.5 hours.
How many minutes will it take for 87.5% of the administered dose to be eliminated? You can assume the drug is fully distributed and follows a first-order elimination process.
270 minutes
100% 50% 25% 12.5%
87.5% eliminated, 12.5% remaining.
From the diagram above this will be 3 x half-life = 4.5 hours 4.5x 60= 270 minutes
You are a pharmacist in an extemporaneous preparation manufacturing unit. You receive an order for salicylic acid 15% w/w cream. You have 100 g of salicylic acid 5% cream in stock.
How much salicylic acid, in grams, do you need to add to make a 15% cream? Give your answer to two decimal places
11.76g
Step 1: What weight of the original cream is drug and diluent?
100 g of a 5% cream = 5g drug and 95 g diluent
Step 2: The final cream is 15% drug, with the remaining 85% being diluent, i.e. 95 g (we are not adding diluent so this amount stays the same).
If 85% = 95 g
15% = 95 x 15/85 = 16.764g
Step 3: The final cream contains 16.764 g salicylic acid but we already had 5 g, so we add:
16.764 g – 5 g = 11.76g (to 2dp) salicylic acid
A 37-year-old man weighing 54kg is taking 8mg of ondansetron 1 hour prior to chemotherapy, the calculated volume of distribution is 2.5L/kg, and the elimination half-life is approximately 3 hours. Ondansetron has a bioavailability of 60%, and peak plasma concentration is achieved in approximately 1.5 hours.
What is the plasma concentration in micrograms/L after 12 hours from achieving the peak concentration? Give your answer to two decimal places
Answer:2.22micrograms/L
Vd = 54 x 2.5L/kg =135L
Bioavailability 8mg x 0.6 = 4.8mg
12 hours / 3 hours - 4 times
4.8 - 2.4 - 1.2 - 0.6 - 0.3
0.3mg = 300mcg
300mcg/ 135L = 2.22mcg/L
A 36-year-old man has been suffering from psoriasis for many years, he has been in remission for a while but since taking lithium for a few months, his psoriasis has been exacerbated. The GP has advised on a course of topical steroid cream, ClobaDerm (clobetasol propionate 0.05%). He is to apply the cream twice daily to his hands, arms, back, face, and neck. 1 fingertip unit (FTU) is equivalent to 500mg of cream. For adults, the recommended FTUs to be applied in a single dose are:·
0.5 FTU for genitals·1 FTU for hands, elbows, and knees·
1.5 FTUs for the feet, including the soles·
2.5 FTUs for the face and neck·
3 FTUs for the scalp·
4 FTUs for a hand and arm together, or the buttocks·
8 FTUs for the legs, including the foot, chest, or back
Calculate the quantity of clobetasol propionate (mg) that he will use per day. Give your answer to two decimal places
9.25mg
a hand and arm together = 4 x 2 (2 hands and 2 arms) x 2
back = 8 x2
face and neck = 2.5 x 2
total = 37 FTU
1FTU = 500mg
37 FTU = 18500mg
18500mg = 18.5g
0.05g in 100g
x in 18.5g
x = 0.00925g = 9.25mg
