Return to professional practice drug calculation

1
MOD001604: Understanding and Responding to Acute Changes in Health
N. Abdulmohdi
Faculty of Health, Social Care and Education
Acute Care Department
Drugs Calculations Workbook
Return to Professional Practice
Student Name:.............................................
Cohort:............................................................
Date .................................................
The last update March 2014

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Contents
Introduction 3
Part 1: Essential 4
Section A: Numeracy 5
Section B: Oral drug Calculations 7
Section C: Drug dosages for injections
13
Section D: Intravenous Drips and Infusion
15
Section E: Fluids
20
Section E: Brief Drug profile
22
Part 2: Optional
Drug calculation of dose in mcg/min
26
Drug calculation of dose in mcg/kg/min
27
Drugs level
29
Drug overdose
30
Reflection
31
Know your drug
32

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Introduction
Medicines are powerful tools in treatment that, if used improperly, are potentially
dangerous. The safety and handling of medicines are of great importance to the
registered nurse who is required to be able to account for a medicine from the time of
ordering through to the administration to a patient. As a student nurse you must
acknowledge the limits of your developing professional competence and obtain help
and supervision from a competent practitioner until you have acquired your
registration and the requisite knowledge and skill.
The Code: Standards of conduct, performance and ethics for nurses and midwives
(NMC 2008) states:
• You must have the knowledge and skills for safe and effective practice when
working without direct supervision
• You must recognise and work within the limits of your competence
• You must take part in appropriate learning and practice activities that maintain
and develop your competence and performance
This workbook is divided to two main parts an Essential part 1 and an Optional part
2.
NMC Standards for Medicines Management (2008)
Before proceeding with the activities within this workbook, please access the following
document ‘NMC Standard for Medicines Management’ (2008). An electronic copy (pdf) of
the Standard is available via the NMC website, which you can download and save from the
following website:
http://www.nmc-uk.org/Documents/NMC-Publications/NMC-Standards-for-medicines-management.pdf
Patient Group Directions
A relatively recent circular (SEP 09) from the NMC was distributed about Patient Group
Directions (PGDs) in relation to the student nurse’s role in the supply/administration of
medicines.
Student nurses cannot supply and/or administer medicines under a PGD even if under direct
supervision (NMC 2009). PGDs are specific written instructions for the supply and/or
administration of a licensed named medicine including vaccines to specific groups of patients
who may not be individually identified before presenting the treatment (NMC 2009). Please
access the circular via the following website:
http://www.nmc-uk.org/Documents/Circulars/2009circulars/NMC%20circular%2005_2009.pdf

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Part 1: Essential
This part contains essential aspects that all students need to do during their facilitated
group session.
Aim
To develop third year student nurses knowledge and skill in performing common drug
calculations
Learning Outcome
• Student nurses will be able to demonstrate safe practice with common drug
calculations
• Student nurses will be discuss the relevance of particular drugs in acute care
settings.
Section A: Numeracy
What we measure S.I. (international system) Symbol
Length Metre m
Weight(mass) Gram g
Volume Litre L
Temperature Degree Celsius ºC
Order of Size Prefix Symbol
One Thousand Kilo K
One Thousandth Milli M
One Millionth Micro Micro

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Arithmetic
With any type of exercise it is important to warm up the respective part of the body
you intend exercising to prevent a strain injury. Our brains are no exception! So here
are a few mental warm up exercises for you. Try not to use a calculator, as the aim of
this warm up exercise is to stimulate your mathematical brain without the use of
assistance
a. 54 ÷ 4 = b. 12.9 + 11.7 = c. 5.25 x 4 =
d. 2119 – 88 = e. 95 x 2.44 = f. 75% of 160 =
g. 1300 ÷ 12 = h. 25 x 8 ÷ 5 – 6 = i. 54 x 95 ÷ 4 =
j. 107 x 5 ÷ 12 = k. 143 + 94+ 49 - 500 ÷ 35 =
l.) 527 ÷ 8 =
Basic exercises
a. Complete
o 1 Kilogram = ............grams (g)
o 1 gram = ....................milligrams (mg)
o 1 milligram =…….....micrograms (mcg or µg but better not to abbreviate)
o 1 Litre =……......……millilitres (ml)
………………………………………………………………………………………

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b. Change
o 0.07g = how many milligram? =
o 0.30 litre = how many millilitre? =
o 1525 microgram = how many milligram? =
o 600milligram = how many gram? =
o 905 millilitres = how many litres? =
…………………………………………………………………………………………..
c. A Drug is available as 1 mg in 10ml:
How many micrograms per ml?
What volume contains 10 microgram?
How many micrograms in 10ml?
PLEASE COMPLETE DURING DRUG CALCULATION SKILLS
GROUP WORK SESSION.
There are three main ways drugs may be administered. Injection, orally or
intravenous infusion. So we need to look at how to calculate dosages for each.
After each calculation, ask yourself is the dosage calculated a realistic answer, if
not then check your calculations.

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Section B: Oral drug Calculations
1. Tablets
Tablets come in different strengths. The analgesia
Ibuprofen for example is available in 200mg tablets and
400mg tablets. When checking a prescription it is vital
that you read the label of the box/bottle/container very
carefully
Tablet calculations
When administering tablets the nurse needs to determine the number of tablets based
on the doctor’s prescription and the strength of tablet made available by the
pharmacist.
Dosage for oral medication
For example
Mr Jones has been prescribed 150mg of Aspirin. The pharmacist has supplied
Aspirin 75mg tablets.
The nurse therefore gives Mr Jones 2 tablet of Aspirin 75mg.
Because 150 = 2
75
Mr Smith has been prescribed 1000mgs of Flucloxacillin (an antibiotic). The
pharmacist has supplied Flucloxacillin 500mgs tablets.
The nurse therefore gives Mr Smith 2 tablets of amoxicillin 250mg.
Because 1000 = 2.
500
Of course if you find it easier to think of it as how many times 100 make up 300 this is
OK
Dose (Volume) = what you want .
what you’ve got

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Exercise 1
Have a look at the following prescriptions and calculate the number of tablets the
patients should be given.
1. Mr Short has been prescribed 100mg of atenolol by his doctor. You have a
ward stock of 25mg tablets.
How many would you give?_________________________
What is atenolol _______________________________________________________
2. Mrs Turner has been prescribed 6m g of haloperidol. Stock tablets are 1.5mg.
How many tablets would you need to give?______________________
Haloperidol is used to treat_______________________________________________
3. A patient is ordered Cimetidine 400mg orally. You have 200mg tablets in
stock.
How many tablets should you give?_______________________
What is Cimetidine?____________________________________________________
4. Analgesia prescribed for a patient is 0.06 grams of codeine phosphate.
How many 30mg tablets would you need to give__________________
What is codeine phosphate?________________________________________
5. Mr Johnson has been prescribed 30mg of Prednisolone. The Pharmacist has
supplied Prednisolone 5mg tablets.
Number of tablets required ___________
What is Prednisolone?___________________________________________________
6. Miss Patel has been prescribed 10 mg of Linisopril. The Pharmacist has
supplied Linisopril 5mg tablets.
What is
Linisopril?______________________________________________________
7. Mrs O’Reilly has been prescribed 2.5mg of Bendroflumethiazide. The
Pharmacist has supplied Bendroflumethiazide 5mg tablets.
What is Bendroflumethiazide?____________________________________________

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Tablet calculations involving conversions
In some instances the units used in the prescription does not match the units the
tablet’s box/bottle/container.
For example
Mr Williams has been prescribed 1.5g of sulphasalazine (a drug for ulcerative
colitis). The pharmacist has supplied sulphasalazine 500mg tablets.
The nurse therefore gives Mr Williams 3 sulphasalazine 500mg tablets
To determine the correct amount of tablets the nurse first ensured that she converted
the prescription to the same units as the tablets,
Exercise 2
Have a look at the following prescriptions and calculate the number of tablets the
1) Mr Windsor has been prescribed 1g of Amoxicillin. The pharmacist has
supplied Amoxicillin 500mg tablets.
Number of tablets ___________
What is Amoxicillin?________________________________________________
2) Mrs Davies has been prescribed 0.8g of Aciclovir . The pharmacist has
supplied Aciclovir 400mg tablets.
Number of tablets ____________
What is Aciclovir?___________________________________________________
3) Miss Khan has been prescribed 1.2g of Slow-K. The pharmacist has supplied
Slow-K 600mg tablets.
Number of tablets _____________
What is Slow-K?____________________________________________________
4) Mrs Cameron has been prescribed 125 mcg of Digoxin. The pharmacist has
supplied Digoxin 0.25mg tablets.
Number of tablets _____________
What is Digoxin?___________________________________________________
5) A patient is receiving co-codamol 30/500, 4 times a day.
a) What are the drugs that make the co-codamol? .................................
b) What 30/500 means? ....................................................................................

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c) What specific drugs you shouldn’t give with this drug?
..............................................................................................................................
Exercise 3
Bearing in mind that the number of tablets given at any one time should be as
few as possible, which tablets would you give in the following situations?
1. Oral Warfarin 7mg is prescribed. You have 1mg, 1mg, 3 mg and 5mg, strengths in
stock……………….............................................................................
2. Oral Thioridazine 75mg is prescribed. You have 10mg, 25mg, 50mg, and 100mg
strengths in stock…………………………..........................................
2. Medications in liquid forms
For many reasons patients may be unable to swallow tablets. In such
instances patients may be prescribed tablets in liquid or syrup form.
Some medications are delivered by injection.
The labels on bottles/containers of liquid medication state the
substances concentration and allow the nurse to determine how much
syrup/fluid to give.
Imodium syrup (for diarrhoea) has a concentration of 1mg per 5mL
Liquid medication calculations
When administering medication in liquid form the nurse needs to determine the
volume of liquid to administer based on the doctor’s prescription and the
concentration of liquid/syrup/suspension made available by the pharmacist.
To work out the correct volume of liquid nurses should apply the following formula
It is very important that when using the formula that the dose required and dose
available are the same unit (i.e. both mg or g).
Volume Required = Strength required x Volume of stock solution
Stock strength

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For example
Mrs Baines has been prescribed 4mg of Imodium. The syrup has a concentration of
1mg per 5mL.
By using the formula the nurse can calculate the amount of syrup Mrs Baines needs
Therefore
4 (mg) x 5mL
1 (mg)
4 divided by 1 = 4.
4 x 5 = 20
The nurse therefore gives Mrs Baines 20mls of Imodium syrup.
Exercise 1
Have a look at the following prescriptions and calculate the volume of liquid the
1) Mr Brown has been prescribed 750mg of Paracetamol suspension. The
pharmacist has supplied Paracetamol 250mg per 5mL.
Volume of Liquid _____________
What is Paracetamol?___________________
2) Mrs Turner has been prescribed 1mg of Chlorphenamine. The pharmacist has
supplied Chlorphenamine 2mg per 5mL.
What is Chlorphenamine?___________________
3) Oliver has been prescribed 15mg of Senna. The pharmacist has supplied 7.5
mg per 1mL.
Volume Required is the amount of stock to be injected into the patient
Strength Required is the amount of drug required for the patient
Stock Strength is the amount of drug in the stock per an amount of volume (per
ampoule)
Volume of Stock Solution is the volume that contains the amount of drug (volume
of the ampoule)
Volume Required = Strength required (unit) x Volume of stock solution (ml)
Stock strength

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What is Senna?__________________________________________________
4) David has been prescribed 500 micrograms of Dexamethasone. The
pharmacist has supplied Dexamethasone Solution 2mg per 5mL.
What is Dexamethasone?___a _____________________________________
5) Mr Churchill has been prescribed 15mg of Oramorph . The pharmacist has
supplied Oramorph 10mg per 5mL.
What is Oramorph?______________________________________________
6) A patient is prescribed 25mg of Pethidine intramuscularly. The ward stock is
50mg in 1 mls of solution. How many mls of solution would you need to
give?_____________________
What is Pethidine?_____________________________________________
7) A solution contains Furosemide (10mg/ml). How many mgs would the
following amounts contain?
a. 5ml of solution= _______________
b. 25mls of solution= _______________________________________
8) 500mg of Sodium Valporate is required orally by a patient. Ward stock is
200mg per 5mls.How many mls would you need for the patient?_______
What is this drug for?_____________________________________________
9) A solution contains Morphine Hydrochloride 2mg / ml. How many milligrams
of Morphine Hydrochloride are in 7ml of the solution?...........................
10) 500mg is prescribed every 8hours of Fusidic acid and you have 250mg/5mls
Fusidic acid Syrup in stock. What volume would you give?...10..............
What is Fusidic acid?-------------------------------------
11) A suspension contains Erythromycin 125mg / 5ml. How many milligrams of
Erythromycin are in 20ml of the suspension?.............................
What is Erythromycin?_______________________________________________

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Section C: Drug dosages for injections:
There is one formula to calculate the Volume Required for an
injection:
Example: Injections
150mg of Ranitidine is prescribed and each ampoule contains 75mg in 2mls
The availability is given in terms of the concentration
The formulae is 150 X 2 = 4ml
75
1. A post op medication of Morphine 20mg has been prescribed to be given Intra-
muscularly .Each ampoule contains Morphine 10mg in 1ml.
Calculate the volume required?
2. A female patient is to have 1000 units of heparin. The stock ampoule contains
5000 units of heparin per 1 ml.
Calculate the required volume?
What is heparin?_______________________________________________________
3. You have Pethidine for injection 100mg in 2ml. A woman requires only 75mg. How
much do you draw up? ________________________________________
4. A woman is prescribed 1.2 g Penicillin by slow IV injection. Penicillin comes in vials
of 600mg. How many vials will you need? ________________________________
What is Penicillin?_______________________________________________________
5. You need to give 150mg of a drug by IM injection. It comes in 250mg per 10ml
ampoules. How much do you need to draw up? ___________________________
6. A patient is prescribed 350mg of gentamicin. The drug concentration is 2ml
ampoules, which contain 40mg/ml., Will 4 ampoules be enough for the prescription?
If not many ampoules would be required?
Volume Required = Strength required (unit) x Volume of stock solution (ml)
Stock strength

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7. A vial of amoxicillin 500mg is reconstituted with water for injection giving a
concentration of 200mg/ml. Calculate the volume of this solution to be draw up for
injection if the prescription is for:
a. 50mg=
b. 90mg=
c. 120mg =
8. A patient requires 100mcg of naloxone. The drug concentration is 400mcg /ml.
How many mls would you draw up?________________
What is this drug for?_______________________________________________
9. 13mgs of morphine sulphate is prescribed for a patient. Your colleague draws up
20mgs of morphine and mixes the solution up in 10ml of normal saline. Giving a
concentration of 2mg/ml. how much solution would you give the
patient?____________________
10. 1Stock heparin has strength of 5000 units per ml. What volume must be drawn up
to give 6500 units?__________________________
Patient safety depends on accurate I.V. drug dosing; precise calculations are essential
to this process. Nurses shouldn’t be apprehensive when I.V. drug dosages are
presented in practice. Use calculations conveyed in this workbook as a first step.

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Section D: Intravenous Drips and Infusion
The rate of flow of fluid down intravenous infusion lines must be
regulated and this is often controlled by a device known as an infusion
controller. The controller measures precise volumes of liquid and releases
tiny droplets, each of exactly the same volume, down the IV line (tube) at
precise intervals. The infusion controller has a keypad or thumb-wheel which allows
the operator to alter the flow of liquid. Some controllers require you to set the Flow
Rate, which is measured in Milliliters per Hour. Others require you to set the Drip
Rate, measured in Drips per Minute. It is important that you know which you are
dealing with.
This will be written on the machine itself.
To calculate the Flow Rate, this is simply the volume in ml divided by the duration in
hours. Both these values will be prescribed.
Example: A patient requires 500ml IVI over twelve hours. What is the flow rate?
Answer 500 divided by 12 is 41.66ml/hr . If you do not the facility to enter decimals
then round to the nearest whole number. The answer would then be 42ml/hr.
If you want to calculate the rate per minute
500 . = 0.69 ml/minute
12 X 60
On some types of flow controller, the size of each drop of liquid given is governed by
the internal mechanics of the controller. It is fixed at the factory and cannot be altered.
This constant quantity gives rise to the "drop factor" which is the number of drops
which make up every millilitre of fluid delivered. Two common sizes are 20 drops
per ml and 15 drops per ml. A special paediatric infusion controller is available
which delivers 60 drops per ml.
The Drop Rate is defined by (1) below:
Drop rate = total drops (1)
time in minutes
If the total volume of fluid is given in millilitres and the drop factor for the controller
is known (written on the machine), the total number of drops which the patient will
receive can be calculated by the expression:
Total number of drops = drop factor X volume in ml (2)
Dose (ml) = Flow rate (ml/hr)
Time (hr)
Dose (ml) = Flow rate (ml/min)
Time (hr) x 60 min

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Also, if the time is given in hours, we can calculate the time in minutes from:
60 X time in hours (3)
So the formula in expression (1) can be rewritten using expressions (2) and (3) as:
(4)
Example: 500ml of 5%dextrose solution is to be given intravenously. The infusion
controller has a drop factor 20 drops per ml and you are instructed to ensure that the
patient receives this volume in 12 hours. What should the drop rate be set to ?
Answer: Drop rate = 20 drops per ml X 500ml = 13.89
60 X 12 hours
Note 1: that it is necessary to round to the nearest whole number, because infusion
controllers which are calibrated to operate in drops per minute do not have the facility
for decimals, so the answer would be 14 drops per minute.
Note 2: standard given set have a drip factor of 15 drops/ml used for crystalloid
infusion, but blood transfusion set usually have a drip factor of 20drops/ml, check the
given set pack for the drip factor and suitability for use.
Exercise1
1. If a patient requires 500ml in 6 hours what is the flow rate (give your answer to two
decimal places)
..................
2. If a patient requires 1500ml in 12 hours what is the flow rate (give your answer to
two decimal places)
....................
3. If a patient is to be given 250 by IVI using a controller with a drip factor of
20drops/ml over 6 hours, what would you set the drip rate to (round to the nearest
whole number)
....................
4. If a patient is to be given 500 by IVI using a controller with a drip factor of
20drops/ml over 12 hours, what would you set the drip rate to (round to the nearest
whole number)
....................
1. A patient is prescribed 250 ml by IVI using a controller with a drip factor of 15
drops/ml for 5 hours. But after 2 hours of initiating this regime the prescribed
doctor came and said the team agreed to discontinue this regime and he prescribed
Drop rate = drop factor X volume in ml
60 x time in hours

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a different fluid plan for your patient? How much liquid did your patient received
so far?
……………………………………………
2. Mr Smith has been prescribed Omperazole 80mg /2ml IV once a day. In order to
give as a slow infusion it needs to be diluted in 100mls of 5% Dextrose and
administered over 1 hour. If you are using a standard gravity drip rate giving set
where 20 drops = 1ml how many drops per minute will you need to set the
infusion at to ensure it is administered correctly?
...................................................................
3. A patient has been prescribed 500 mls 5% Dextrose over 6 hours. How many mls
per hour will they receive?
.........................
4. A patient is to receive one litre of 0.9 % Normal Saline. If a volumetric infusion
pump is set at 130ml/hour, how long will the pump take to give the solution?
......................................................
5. Vancomycin 1000mg is diluted in 250mL of compatible infusion fluid. This
infusion has to be given over 100 minutes. What rate should you set the infusion
pump at, in ml/hr, to deliver this dose?
............................................................................
6. Furosemide 100mg is diluted in 50mL of compatible infusion fluid and given over
12.5 minutes. What rate should you set the infusion pump at, in mL/hr to deliver
this dose?
............................................................................
7. A patient-controlled analgesia (PCA) infusion pump contains morphine 1 mg/ml.
The patient receives a bolus dose of 1 ml when the button is pressed. If the
minimum period between doses (“lock-out time”) is set to 5 minutes, what is the
maximum dose of morphine available to the patient in mg/hr?
............................................................................

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8. One unit of blood contains 300mls; this needs to be given to your patient over
3hrs. Using a blood giving set with drop factor 15 drop/ml, what would be the
mls/hour and drops per minute for this infusion?
9. A patient has a peripheral line insitu. It is fluid is running at 35ml/hr. How much
fluid will the patient receive in?
a. 2 hours=
b. 8 hours=
c. 12 hours =
10. Mr Brown developed atrial fibrillation and he is attached to a cardiac monitor,
complete assessment was done including an 12 leads ECG and vital signs, Mr
Brown has a stable BP, the doctor prescribed the following prescriptions:
a. Amiodarone 300 mg diluted in 100ml total volume of 5% dextrose water
delivered by control infusion pump over 1 hour.
Followed by
b. Amiodarone infusion 900mg diluted in 250ml total volume of 5% dextrose
delivered by control infusion pump over 23 hours.
Calculate the flow rate per hour for
a______________
b______________
11. Mrs Smith has been prescribed 500mg of Metronidazole in a total volume of
100mls intravenously over 30 minutes. You are using a gravity drip device to
deliver the drug.
a) How many mls per minute will the drip need to run at to ensure you deliver it
over 30minutes?_______________________________
b) How many drops per minute will this equal if you are using a standard giving
set where 1ml = 15 drops? _______________________________________

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Section E: Fluids
Weight in volume (w/v) is when a solid is dissolved in a liquid: 1% w/v means that in
every 100mL of the solution you will find 1g of drug.
E.g. Glucose 1% (w/v) = every 100mL has 1g Glucose.
Exercise
1) How many g of Glucose would there be in 500mL of 5% Glucose?
....................................................
2) How many g of glucose would there be in 50 ml of 50% glucose?
.................................................
Give one indication for using 50% glucose in practice.......................................
3) How many g of sodium chloride in 1000 ml of 0.9% sodium chloride?
................................................
Give one indication for using 0.9% sodium chloride fluid in practice......................
4) How many g of sodium chloride and how many g of glucose in 300mls of
(Dextrose saline: 4.3% glucose and 0.18% saline).
.................................................
5) How many milligram of lidocaine (lignocaine) are there in 2 ml of 0.5%
lidocaine?
..........................................................
Give one indication for using lidocaine in practice................................................
8.4% w/v Sodium Bicarbonate in 100mls is equal to 8.4 grams of Sodium Bicarbonate in 100mls.
In the same way as 1% w/v Lignocaine = 1 gram of Lignocaine in 100mls.
In the same way as 0.9% w/v Sodium Chloride = 0.9 grams of Sodium Chloride per 100mls.
In the same way as 50% w/v Glucose = 50grams of Glucose per 100mls
In the same way as 0.4%w/v Sodium Chloride

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6) How many milligram of potassium chloride are there in 2 ml of 0.3%
potassium chloride solution?
..........................................................
Give one indication for using potassium chloride in practice................................
7) How many g of sodium bicarbonate in 400mls of 8.4% sodium bicarbonate
solution?
..........................................................
Give one indication for using sodium bicarbonate in practice.............................
8) How many g of Mannitol in 250mls of 20% Mannitol solution?
..........................................................
Give one indication for using Mannitol in practice .............................................
Note:
To calculate milligrams from a ratio e.g. 1:1000 it is essential that the following is remembered.
The number in front of (:) symbol will equal the number of milligrams (mg). The number after
the (:) symbol will indicate the number of millilitres (ml). Hence:
a) Adrenaline 1: 10,000 = 1 mg of Adrenaline in 10,000millilitres.
NOT TO BE CONFUSED WITH
b) Adrenaline 1: 1000 = 1 mg in 1000 millilitres.
c) Adrenaline 1: 1000 = 1 mg in 1000 millilitres (ml).
Q1: Which is the stronger concentration? Explain your answer
a) Or b)
Q2: A patient begins to have an anaphylactic reaction whilst the qualified nurse you are working
is administering a dose of Penicillin. They immediately stop the administration of the Penicillin
and an emergency call for help is put out. The doctor arrives and wants to give Adrenaline 500
microgram (mcg) intramuscularly. You have adrenaline 1:1000 strength (1ml vial).
How much will you draw up to ensure you have 500mcg?
........................................................

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Few common drugs in Acute Care settings
Write a brief drug profile for each of the drugs below
If you want to write a more detailed profile use last page of this workshop
1. Adrenaline .
Mode of action or group:.......................................................................
Indication:..............................................................................................
Side effects.............................................................................................
Method of administration......................................................................
Considerations and precautions .............................................................
2. Atropine .
Indication:..............................................................................................
Side effects.............................................................................................
3. Adenosine .
Indication:..............................................................................................
Side effects.............................................................................................
4. Amiodarone .
Indication:..............................................................................................
Side effects.............................................................................................

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5. Noradrenaline .
Indication:..............................................................................................
Side effects.............................................................................................
6. Dobutamine .
Indication:..............................................................................................
Side effects.............................................................................................
7. Dopamine .
Indication:..............................................................................................
Side effects.............................................................................................
8. Atenolol, Metoprolol, Esmolol .
Indication:..............................................................................................
Side effects.............................................................................................

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9. Verapamil .
Indication:..............................................................................................
Side effects.............................................................................................
10. Furosemide .
Indication:..............................................................................................
Side effects.............................................................................................
11. Aspirin .
Indication:..............................................................................................
Side effects.............................................................................................
12. Nitrates .
Indication:..............................................................................................
Side effects.............................................................................................

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13. Morphine .
Indication:..............................................................................................
Side effects.............................................................................................
14. Digoxin .
Indication:..............................................................................................
Side effects.............................................................................................

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Part 2: Optional Part
Some of the components below will be relevant to a number of you but not to all;
however it would be useful to have an insight about the drugs that are used in critical
care settings.
Drug calculation of dose in mcg/min
This method is required when calculating quantities of potent drugs given to patients
in the critical care areas.
Formula
Example:
While receiving hand over of a patient with acute coronary syndrome, your patient is
connected to gylceryl trinitrate (GTN) infusion. There is 50 mg of GTN diluted in
100ml of 5% dextrose solution running at 5ml/hr via an infusion pump. Calculate the
dose in mcg/min.
Apply the formula above
50 mg x 1000 (convert mg to mcg) x 5 = 41. 7 mcg/min
100 ml 60 (convert hr to min)
Exercise 1
While receiving hand over of a patient with acute coronary syndrome, your patient is
connected to Isosorbide Dinitrate (Isoket) infusion. There is 25 mg of GTN diluted in
50 ml of 5% dextrose solution running at 3 ml/hr via an infusion pump. Calculate the
dose in mcg/min.
Stock dose (mg) x 1000 (convert mg to mcg) x ml/hr = Require dose (mcg/min)
Stock volume (ml) 60 (convert hr to min)
Critical CaCritical CaCritical CaCritical Carererere sectionsectionsectionsection

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Drug calculation of dose in mcg/kg/minute
This method is required when calculating quantities of potent drugs given to patients
in the critical care areas.
Example
Your patient is receiving dopamine infusion 15ml/hr. The medication dilution is
400mg of dopamine in 250mls of 5% glucose solution. The patient weight is 85kg.
What is the dose of dopamine your patient receiving in mcg/kg/min?
Apply the formula above
1. Your patient is receiving dopamine infusion 10ml/hr. The medication
dilution is 400mg of dopamine in 250mls of 5% glucose solution. The patient
weight is 70kg. Calculate the dose of dopamine your patient receiving in
mcg/kg/min?
2. Your patient is receiving adrenaline infusion 10ml/hr. The medication
dilution is 5mg of adrenaline in 250mls of 5% glucose solution. The patient
weight is 75kg. Calculate the dose of adrenaline your patient receiving in
mcg/kg/min?
Stock dose (mg) x 1000 (convert mg to mcg) x . ml/hr .= Require dose (mcg/kg/min)
Stock volume (ml) 60 (convert hr to min) patient weight (kg)
400 (mg) x 1000 (convert mg to mcg) x . 15ml/hr .= Require dose (mcg/kg/min)
250 (ml) 60 (convert hr to min) 85 (kg)
1.6 x 16.7 x 0.176 .= Require dose (mcg/kg/min)
4.7 mcg/kg/min .= Require dose (mcg/kg/min)

27
N. Abdulmohdi
3. Your patient is receiving dobutamine infusion 10ml/hr. The medication
mcg/kg/min?
4. Your patient is receiving noradrenaline infusion 2ml/hr. The medication
mcg/kg/min?

28
N. Abdulmohdi
Drug serum level and therapeutic effects
Explain why some of the drugs need its serum level to be checked regularly? Use the
drugs below as examples to answer
Digoxin
Vancomycin
How can we adjust some of the drug dosage? Use the drugs below as examples to
answer
Warfarin
Heparin
Rampril

29
N. Abdulmohdi
Drug overdose
What would you do if you strongly suspect that a patent has been overdosed? Use the
drugs below as examples to answer
Morphine
Heparin
Warfarin
Digoxin
Verapamil
Midazolam

30
N. Abdulmohdi
Reflection on practice
Reflect on your experience of administering medication. Write in
sentences what happened, how did it make you feel and what would
you do differently (if anything) next time you need to administer
medication to a patient/client.
What happened?
How did it make you feel?
What would you do differently (if anything) next time?

31
N. Abdulmohdi
"Know Your Medicines"
Name of the Drug (Generic & trade name) What group of drugs does it belong to? (e.g.
analgesics or antibiotics etc)
What preparations are available ( e.g. 5mg & 10mg tablets
or 10ml ampoules etc)?
What routes of administration is the medicine given by?
What is the usual dose and frequency?
What is the medicine used for? (e.g. treat asthma etc).
What is the action of the drug? (How does it work e.g.
bronchodilator: explain any terms use find)
Are there any special precautions, preparation issues or administration issues that need consideration and that are
specific to this medicine? (e.g. administer with food).
Are there any known side effects?
Any contraindications?
Any patient monitoring required? (e.g. lying and standing
BP, pulse rate measurement before administration etc)
How the drug prepared is (e.g. dissolved in water
etc).
If a tablet can it be crushed? (If not, why not?)

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