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INTENSIVE CALCULATIONS COURSE�� OSPAP STUDENTS & PHARMACY STUDENTS.��SESSION ONE – QUANTITY TO SUPPLY.� INTENSIVE revision programme

SMASH CALCS

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OPENING REMARKS

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  • book sign means resource questions
  • USE LAPTOP OR DESKTOP
  • CALC SESSION 1 of 12
  • GET CALCULATOR. GET NOTES PAD and PEN
  • PAID REVISION SESSION so , DO NOT SHARE LINK/ MATERIALS for this session it against our terms and conditions.
  • MENTAL BREAK 5 – 10 MINS
  • YOU WILL BE SENT PRACTICE QUESTIONS tomorrow AFTER SESSION
  • STAY ACTIVE ATTEMPT QUESTIONS AND ASK QUESTIONS

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QUESTION ONE

  • A patient requires Hypromellose 0.3% eye drops . Calculate how many 5ml bottles you would supply.

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  • 2 drops in both eyes TDS, then 2 drops in each eye QQH, then one drop in left eye QDS then continue one drop in LE, BD for a month.
  • Round answer to nearest whole number

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ANSWER ONE

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SOLUTION

  • 2 X 2 = 4
  • 4 X 3 = 12
  • 2 X 2 = 4
  • 4 X 6 = 24
  • 1 X1 = 1
  • 1 X 4 = 4
  • 1 X 1 = 1
  • 1 X2 X 28 = 56
  • 12 + 24 + 4 + 56 = 96 NOTE- 1ml = 20 drops
  • 96/20 = 4.8
  • One BOTTLE

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QUANTITY TO SUPPLY - QUESTION 2

  • Mr. X presents a prescription for Gabapentin 100mg capsules.
  • Take one capsule TDS daily for 3 days, then 2 capsules TDS for 4 days then 3 capsules BD for three days then 4 capsules TDS for a month. You supply your total stock of 39 capsules.
  • How many capsules are owed to Mr. X?

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ANSWER 2

  • 3 x3 = 9
  • 6 x 4 = 24
  • 6 x 3 = 18
  • 12 x 336
  • 336 – 39= 348

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  • ANSWER 348

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QUESTION 3

Tom is a 9-year-old male patient who has been prescribed Phenoxymethylpenicillin suspension at 250mg QDS for 10 days for sore throat whilst in hospital. You only have phenoxymethylpenicillin 125mg/5ml suspension in stock. Each bottle is 100ml. The doctor decides to discharge the patient after 20 doses of the medicine and instructs Tom's mother to continue the course at home until completion. Based on your available stock, you are required to calculate the total volume needed to complete the course upon discharge. 

Express your answer as number of bottles to be supplied.

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ANSWER 3- QUANTITY TO SUPPLY

  • 250mg QDS IS DOSE
  • Total quantity required of stock = 10ml QDS X 10 DAYS = 400ml
  • 20 doses = 10ml x 20 = 200ml
  • 400ml -200ml = 200ml
  • ANSWER IS 200ml = 2 bottles

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QUESTION 4

Mr. P presents to your pharmacy with a prescription for prednisolone tablets. The doctor has prescribed a titrating regimen

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-- Take initial dose of 25mg daily for 1 week, then reduce the daily dose by 5mg per week until the dose is reduced to zero.

You then supplied your stock of 56 tablets to the patient.

Calculate how many prednisolone 5mg tablets you owe this patient?

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ANSWER 4- QUANTITY TO SUPPLY

  • 5 x 7 days = 35
  • 4 x 7 = 28
  • 3 x 7 = 21
  • 2 x7 = 14
  • 1 x7 = 7
  • Total = 105
  • 105 – 56 = 49 tablets

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QUESTION 5

A child is admitted in the hospital ward where you work. The child weighs 14.4 kg is being treated in hospital for suspected pneumonia with benzylpenicillin at the dose of 200 mg/kg/day, given in divided doses every four hours. Single vials of benzylpenicillin contain 600 mg in 2 ml.

Calculate how many milliliters (ml) will provide one dose?

Answer in 1 decimal place.

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ANSWER 5- QUANTITY TO SUPPLY

  • 200 x 14.4= 2880mg
  • Every four hours means six times a day
  • Hence 2880/6 = 480mg
  • 600mg = 2ml
  • 480mg = 1.6ml
  • ANSWER = 1.6ml

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QUESTION 6

Miss Nisha has been prescribed pregabalin by her hospital consultant, to be reviewed in a month’s time. She requires 300 mg OD on days one and two, then, 300 mg BD on days three, four and five, followed by 300 mg TDS thereafter.

The hospital consultant requests 4-week supply in total.

How many capsules should be supplied if each capsule in your stock contains 150 mg of pregabalin?

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ANSWER 6- QUANTITY TO SUPPLY

  • 300mg = 2 capsules
  • Day 1 = 2 caps
  • Day 2 = 2 caps
  • Day 3 = 4 caps
  • Day 4 = 4 caps
  • Day 5 = 4 caps
  • Remaining 23 days = 6 caps x 23 days
  • TOTAL = 154 Capsules total

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QUESTION 7

Miss Kelly’s medication chart comes down from the pediatric ward with a take home prescription for an antibiotic at a dose of 20 mcg/kg three times a day for seven days. You contact the ward and are told that Kelly, age 10, weighs 32 kg.

The drug is available as an oral solution containing 0.1 mg/ml. How many milliliters of the oral liquid would you dispense to ensure sufficient supply for seven days?

ANSWER to 1 decimal place.

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ANSWER 7- QUANTITY TO SUPPLY

  • 32 x 20 = 640mcg
  • 640mcg x 3 times a day = 1920mcg
  • 1920mcg x 7 days = 13440mcg
  • Change 13440mcg to 13.440mg
  • SO, if 0.1mg = 1ml
  • 13.44mg = 134.4ml
  • ANSWER = 134.4ml

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QUESTION 8

A married couple will be travelling to Kenya - a malaria endemic area and require prophylaxis with Malarone tablets. The dose for adults is 1 tablet daily, and they will need to start taking the tablets 1 to 2 days before travel, each day whilst they are within the area and for 7 days after coming back.

The holiday will be for 21 days, how many tablets is required for malaria prophylaxis?

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ANSWER 8- QUANTITY TO SUPPLY

  • Note You should calculate for 2 adults.
  • Also use the higher of 1 to 2 days to ensure maximum protection.
  • 2 + 21 + 7 = 30 tablets
  • 30 tabs x 2 patients = 60
  • ANSWER = 60 tablets

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QUESTION 9

  • Alfie, A male child of 15kg with progressive juvenile chronic arthritis requires treatment with an intramuscular injection of myocrisin. Myocrisin injection contains sodium aurothiomalate 2%w/v. The treatment dose of Myocrisin is 1mg per kg as a single intramuscular injection per week. Before a treatment dose can be given a smaller test dose containing 20% of the full weekly treatment dose should be given to check for allergic reactions. What volume of Myocrisin injection should be administered as a test dose to Alfie ?
  • Answer to 2 decimal places.

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ANSWER 9- QUANTITY TO SUPPLY

  • 1mg x 15kg = 15mg
  • 20% of 15mg = 3mg
  • 2%w/v means 2g = 100 or 2000mg = 100ml
  • 3mg = x
  • X = 0.15ml

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ANSWER 10- QUANTITY TO SUPPLY

  • Mr. Kane usually takes carboceisteine 375mg capsules at a dose of 2 capsules three times a day. He is unable to swallow capsules, and his doctor would like to switch him to carboceisteine 250mg/5ml oral solution. Carboceisteine oral solution is available in 300ml bottles. Calculate how many bottles you would supply for a complete month’s treatment.

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ANSWER 10- QUANTITY TO SUPPLY

  • 250mg = 5ml
  • 375mg = 7.5ml
  • 7.5ml x 2 = 15ml
  • 15ml x 3 times a day = 45ml
  • 45ml x 28 days = 1260ml
  • 1260/300 = 4.2
  • ANSWER = Supply 5 bottles

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RDA - QUESTION 11

  • Amy a 22-year-old patient is taking sodium citrate oral sachets to relieve symptoms of cystitis. She takes the content of one sachet mixed in 200ml of water every 6 hours. Cystitis sachets also contains NaCl and provides a total of 2mmol of Na+ per sachet. The recommended daily allowance (RDA ) of salt for an infant is 1g (0.4g of sodium) and for an adult is 6g (2.4g of sodium).
  • The atomic mass of sodium is 23.

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  • What percentage of Amy’s recommended daily salt allowance is contained in her daily dose of cystitis relief sachets?
  • ANSWER TO 1 .D.P
  • Watch London Pharmacist Network videos on YouTube

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ANSWER 11

  • FOUR SACHETS per day = 2mmol x 4 = 8 mmol
  • Using mole = mass / mr
  • 8mmol = mass (mg)/ 23 mmol/mg
  • Mass = 184mg or 0.184g

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  • Then if 2.4g of Na+ = 6 g of salt
  • 0. 184g Na+ = 0.46 g of salt

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  • HENCE 0.46g/6g x 100 = 7.666
  • ANSWER = 7.7%

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RDA - QUESTION 12

  • Angel a-6-month old baby has been prescribed Gaviscon sachets at a dose of one sachet with feeds every four hours. Her mother has been asked to continue treatment for a month then review. Gaviscon sachet contain 0.92 mmol of Na +.
  • RDA of salt for Angel is 1g (equivalent to 0.4g sodium) per day.
  • What percentage of Angel’s recommended daily sodium allowance is contained in her daily dose of Gaviscon sachets?
  • ANSWER TO 1.D.P

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ANSWER 12

  • Gaviscon Infant Sachets contains 0.92mmol Na+/dose.
  • 0.92 x 23 = 21.16mg per dose
  • 6 doses a day = 6 x 21.16 = 126.96
  • SO, 126.96 x 100/400= 31.74%
  • ANSWER = 31.7%

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THANKS FOR PARTICIPATING

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