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Calculating the number of tablets or volume of elixir

Here are two simple ways that you can use to check the correct drug dose:

Use this formula:

Example: 20 mg of furosemide is prescribed and the ward stock is 5mg tablets:

Find the dosage in the smallest single unit available and divide the prescribed dose by this figure.

Example: 10 mg of temazepam is prescribed and the ward stock is 25 mg in 20 ml elixir. The smallest single unit is 1 ml. Divide 25mg by 20 ml to find out the dosage per ml = 1.25 mg per ml:

Therefore the dosage is:

Calculate the following:

1
Calculation 1

The doctor has ordered 0.5g of erythromycin for your patient. Tablets of 250 mg are available. How many tablets will you give?

Check your answer

2
Calculation 2

A patient has been prescribed 10mg of diazepam. On hand you have diazepam 0.005g tablets. How many tablets will you give?

Check your answer

3
Calculation 3

The doctor has ordered 4mg of codeine. On hand you have 0.002g tablets. How many tablets will you give?

Check your answer

4
Calculation 4

Unfortunately, your patient is feeling no better. He is to be given Chlorpromazine 0.075g. On hand you have Chlorpromazine 25mg/ml. How many mls will you give?

Check your answer

5
Calculation 5

Your patient is still no better. He is to be given 500mg of penicillin. On hand you have penicillin 0.25g tablets. How many tablets will you give?

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6
Calculation 6

The doctor then orders diazepam 0.002g. Available are 1mg tablets. How many tablets will you give?

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7
Calculation 7

He is then prescribed 150mg of phenytoin. The ward stock is 90mg in 5mls elixir. How many mls will you give? For amounts less than 1ml round it off to the nearest hundredth.

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8
Calculation 8

300mg of phenytoin is prescribed and the ward stock is 30mg in 5mls elixir. How many ml will you give? For amounts less than 1ml round it off to the nearest hundredth.

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9
Calculation 9

The doctor then prescribes 15mg of temazepam and the ward stock is 25 mg in 20ml elixir. How many mls will you give? For amounts less than 1ml round it off to the nearest hundredth.

Check your answer