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Formulae and Equations - Medication dosages.
Test Yourself 1.


 

Fried's formula:
Young's formula:
Clark's formula:

Use the above standard formulae to complete the following questions:

Fried's formula 1.
  2.
  3.
   
   
Young's formula. 6.
   
  8.
   
  10.
Clark's formula: 11. A father needs to give his 7 year old son some medicine. The child weighs 23.35 kg.

The prescribed adult dosage is 12 ml every morning and 12 ml every night.

The father uses Clark's formula to determine the equivalent dosage for his son.

How many days will a 200 ml bottle last for the child?

Answer.200 ÷ (2×4) = 25 days.
   
   
   
  15.

Other questions not using the basic formulae:

16. A doctor requires a patient to have 1 litre of a saline solution to be administered intravenously over a period of 5 hours.

At what rate should the solution be administered?

Answer.200 ml/hour.
17. 75 ml of a solution needs to be administered to a patient over 40 minutes.

At what hourly rate is this solution administered?

Answer.113 ml/hour.
18. A doctor requires a patient to have 400 ml of a saline solution to be administered intravenously over a period of 4 hours. There are 20 drops in each ml of the solution.

At what rate in drops/minute should the solution be administered?

Answer.15 ml.
19.If a patient is to receive 300 ml of a dextrose solution in 50 minutes, at what rate (in drops per minute) must the solution be administered? As usual, assume that there are 20 drops per ml.
Answer.33.33 = 34 drops/min.
20.
21. A child weighing 18 kg needs to be given 20 mg of paracetamol for every 2 kg of body weight.

Every 10 ml of a particular medicine contains 120 mg of paracetamol.

What is the correct dosage (in ml) of that medicine for this child?

Answer.15 ml.

17. A patient requires 1800 mL of fluid to be delivered at a constant rate by means of an intravenous drip over 12 hours.

Each millilitre of fluid is equivalent to 20 drops.

How many drops per minute need to be delivered?

Answer.50 drops per minute.

18. An intravenous drip is delivering 30 drops/min. There are 15 drops/mL and 1·2 L of liquid to be delivered.

How long will the drip take to deliver the required dose?

Answer.10 hours.