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• Administer Medications Using Knowledge Of The Principles Of Five Right, Namely, Right Patient ,Right Drug, Right Dosage ,Right Time ,& Right Route.
3. Accurately Interpret Prescriptions Prescribed By The Physician.
4. Appreciate the Importance Of Safe Management & Storage To Protect self & Patient .
• Describe The Action Dosage &Method Of Administration of Drug used In Diseases Of Cardio Vascular System, Gastrointestinal Tract, Respiratory Tract,& Urinary Tract .
• Administer The Above drug & Observation Record & Report Therapeutic Effects & Adverse reactions.
• Appreciate The Nurses Professional Responsibilities In The Administration Of The Above Drugs.
• Method Of Evaluation ;
• Calculations And Interpreting Prescriptions Practice 20%1.Grundy H.F, Lecture notes
• Final Examination 80%
.
• References
• Grundy H. F. Lecture notes on Pharmacology .
• Katzung , B. G. Basic and clinical Pharmacology .
• Laurnce ,D.R.& Bennett ,P.N. clinical Pharmacology .
• Method of Teaching & Learning
• Lecture/Discussion, Demonstrations ,Large & Small group Work, Practice in Calculations & Interpreting Prescriptions.
Definitions ;
Drug
Drug is Substance used in the Diagnosis ,Prevention or Treatment of a Disease .
• WHO Definition – Drug
“ Drug is any Substance or Product that is used or Intended to be Used to Modify or Explore
Physiological Systems or Pathological States
for the Benefit of the Recipient” .
Don at 12 .06.14
• Pharmacokinetics ;
Pharmacokinetic Is the Study of the Absorption , Distribution , Metabolism and excretion of the drug .[ what the body does to the drug ] .
• Pharmacodynamics ;
• Pharmacodynamics is the Study of the Effect of the Drugs on the Body & Their Mechanisms of Action .
(what the drug does to the body .)
Therapeutics ;
Deals with the use of Drugs in the Prevention and Treatment of Disease .
• Toxicology ;
• Deals with the Adverse Effects of Drugs and also the Study of Poisons .
. (detection ,prevention and Treatment of poisoning s .)
• Chemotherapy ;
Chemotherapy is the use of chemicals for the Treatment of Infections . the
Term now also Includes the use of Chemical Compounds to Treat Malignancies .
• Pharmacy ;
Pharmacy is the Science of
Identification , Compounding and Dispending of Drug. It Also Includes Collection ,Isolation ,
Purification , Synthesis and Standardization of
Medicinal Substances .
• History of Pharmacology
• The world Pharmacology is Derived from Greek
- “ Pharmacon” . Man Knew the useful and toxic
Effects of many Plant and Animal Products
Even in Ancient Times. In Early Days There
was a Close Relationship Between Religion &
Treatment of Diseases .The Knowledge of the
Use of Drugs often Rested with the Priest or
Holy man . Drugs were though to be Magical in
Their Actions . Though Medicine developed
simultaneously in Several countries . The Spread of Knowledge was Limited Because of
Poorly Developed Communication Across The
world . Several Cultures Like The Chinese , Roman ,European ,Persian and Many others
Contributed a Great Deal to the development of
Medicine in Early times .
The Drug Prescriptions Included Preparations from Herbs , Plants , Minerals ,Animals . In the Middle Ages , Many
Herbal Gardens Were cultivated Particularly by
The monasteries .
The Earliest Writings on drugs
are the Egyptian Medical Papyrus (1600 B C ) .
Indian’s Earliest Pharmacological writings are
From the “ Vedas” .
Thus several Systems of Medicine Were Tried
but Only a few Survived . By the end of the
17th Century the Importance of Experimentation
and Observation and Scientific Methods of
Study Became Clear . “Francois Magendie” and
“Claude Bernard” Popularised the use of
Animal Experiments to Understand the Effects
Of Drug .
Simultaneous Development of other Branches
Of Science Viz Botany , Zoology , chemistry and
Physiology Helped in the Better Understanding
Of Pharmacology . The Last Century Has Seen
A Rapid of the Subject With several New drugs ,
New Concepts and Techniques Being Introduced
We now Know Much more about Receptors
and Molecular Mechanisms of action of Many
Drugs . Several Diseases which were considered
Incurable and Fatal can now be Completely
Cured With Just a Few Tablets .
at 2012.o6.25.
Sources of Drugs
The Sources of Drugs Could be divide ;
1. Natural sources
2. Synthetic sources
Natural Sources ;
1. Plants (atropine, quinine )
2. Animals (insulin, heparin )
3. Minerals (Aludrox , Iron )
• 4.Microorganisms (Penicillin )
• 5. Human ( Immunoglobulin from Blood )
•
• Synthetic ;
• Most drugs are now Synthesized
• (Neostigmine ,Sulfonamides )
• Pharmaceutical Standards .
• Drug Compendia
• Books are sources of Information on Drugs .
Pharmacopoeias and Formularies are together
Known as Drug Compendia . Drug Compendia
are 2 types.
1. Official Compendia .
2. Non official Compendia .
1. Official compendia
Official Compendia Include
Information sources (or books ) on drugs which
Are recognized by the Government of that
Country as “ Legal standard” .
eg. Pharmacopoeia , Drug Formulary .
.
• Pharmacopoeia
pharmacopoeia is ,the official
Publication containing a list of Drugs and
Medicinal Preparations. It contains a list of drugs
And related substances are Approved for use ,
Formulae and other information needed to
Prepare the drugs . Each country may follow its
Own pharmacopoeia . Eg; British pharmacopoeia ,
Indian Pharmacopoeia, United States
Pharmacopoeia , USSR and Japan Pharmacopoeia.
The international Pharmacopoeia is Published by
WHO in many Languages .All Pharmacopoeias
Are Revised at Regular periods to delete old
Useless drugs and to Include newly introduced
Ones .
Drug Formulary
Also Provides Information on drugs.
The National Formulary is a smaller book that
Contains information on formulation which are
Used Therapeutically .It is Prepared by the
National formulary committee of health
Department. Expert Opinion is also taken from
medical associations ,Hospitals ,Teaching
Institutions and Pharmaceutical Industry in
Preparing in This book .
eg; a). British National Formulary .
b).Ceylon Hospitals Formulary .
c). National Formulary of India.
done at 12.07 .09.
2. Non official compendia
The books other than
The official compendia which provide information
on Drugs . Eg ; Text book , Journals .
Collect & list of name the text book & journals
Professional Obligations of the Nurse Related to Pharmacology .
1.Safe custody of Drugs .
2. Legal Implications
3. Poisonous and Dangerous drug ordinance .
• Nurses Responsibility in Drug therapy.
• 1. Storage .
2.Ordering .
3 .Accounting .
1. Drug Storage (Safe Custody of Drugs .)
• All Drugs are Potentially dangerous and all
Must be Stored in Locked Cupboards Reserved
Specifically for Drugs .
2. Ward Sisters are Legally Authorized to Passes
Controlled Drugs for use on their Wards and
These all other Drugs Issued To the ward are in their Custody .
3. Drugs in Current use may be stored in Drug
Trolleys Provided These are Locked and
Immobilized Between Drug Rounds .
3.Topical Preparations Such as Ointments , Lotions, and Disinfectants ,are also Dangerous.
If Misused and these too Must be Locked in
Cupboards .
4. This has been Mandatory for Many years in
Children Wards.
5. Most Drugs and it is the Pharmacist’s
Responsibility to ensure that the label on the
container Adequate Instructions such as
Store in a Refrigerator . ( maintain in cold chain).
6.All Injections and many Tablets have Expiry
Dates Assigned by the Manufacturer nurse should
be checked this date Regularly and replacement
Before Reaching their expiry date .
Naming of Drugs
A Drug can have two names .
1.Generic (Non Proprietary ) Name.
2.Proprietary (Brand ) Name .
1.Generic name
Name is given by an Official
Agency like WHO and Internationally Accepted .
The drug has the same generic name All over
the world . It gives a clue to the class of the
drug. Eg ; Propanalol ,Atenolol ,metoprolol – all
Are –B blockers.
2.proprietary name
Brand Name Is The Given By Manufacturer.
Hence Each Drug May Have Many Brand Names.
The Main Advantage In Using Brand Name Is
The Consistency Of The Product- Especially
Bioavailability. Done at 12.07.10
Drugs Control
drugs are grouped for legal
Purpose as ;
1. official drugs :-
official drugs are preparations listed
In the pharmacopeia of that country.
2. Dangerous Drugs
Drugs Of Addiction Like Coca
Leaf ,Opium ,Cannabis , And Products Of These
Are All Called Dangerous Drugs .
3.Prescription Drugs done at 12.07.11.
This Drugs Are Those Which
Are Dispensed Only On Prescriptions .
This Is Because Such Drugs Are Considered
Unsafe For Use Except Under Medical Supervision.
E.G. ;- Diazepam , Phenobarbitone .
Drugs Laws
, The Manufacture , Distribution
And , Sale Of Drug Require Specialized Knowledge
Knowledge ,skill , and expertise . They should
Be handled by qualified staff.
Drug laws in which they were passed
1. 1878 – the opium act
2. 1919- the poisons act
3.the dangerous drugs act -1940 .
4.1985 –the narcotic drugs and psychotropic
.
Substances Act .
Cosmetics , Devices And Drugs Act (CDD ACT) .
No 27 of 1980 .
legislative frame work to control the
Use of cosmetics ,devices ,& drugs in the
Srilanka . The act controls:-
1. registration . 2. manufacture .
3. Importation . 4. Transport
5. Sale (Whole Sale & Retail )
6 . Labeling .
7. Advertisement .
8. Distribution Of Drug Samples .
9. Testing .
10 .Distribution Of Outdate Or Spoilt .
Amendment To The Act .
1. Act No 38 Of 1984 .
2. Act No 25 Of 1987 .
3. Act No 12 Of 1993.
This Act Which Regulate And Maintains Powers As
The CDD Authority In Srilanka .
To implement the CDD act & regulations therein
Authorized officers ;-
1. superintend of health service
2 .MOH
3. FDI
4 . Divisional pharmacists
5. PHI
unit - 2
Drug Administration , Pharmacokinetic , Pharmacodynamics , And Dosage
Drug Administration
routes of administration
drugs may be administered
By various routes . The routes can be divided
Into :- 1. oral
2. parenteral
3.local.
1. oral route
this is most common and safest route of
Drug administration . The large surface area of
The GI-tract , different parts help effective
Absorption of the drugs given orally.
advantages :- most convenient and economical ,
Non invasive route , drugs can be self -
Administered.
Disadvantages :-
Absorption Is Needs Time There Fore Slower
Action , Cannot Be Given To Unconscious And
Uncooperative Patient , Some Drug May Be
Destroyed By Gastric Juice , Irritation To The
Gi-tract May Lead To Vomiting ,
2. Parenteral Route
This Routes Administration Of Drugs
Are Directly Delivered Into Tissue Fluid Or Blood.
Therefore In Emergencies Are Very Useful Routes
Of Parenteral Drug Administration Because
The Action Is Rapid And Predictable In Used To
Unconscious Patients .
Advantages :-
Gastric Irritants Can Be Given Parentrally .
It Can Be Used In Patient With Vomiting
Or Those Unable To Swallow .
Disadvantages :-
More Expensive ,May Be Painful ,Injury
To May Be Nerves And Other Tissues
• Parenteral routes include :-
1. injections 2. inhalation
3. transdermal route 4. trans mucosal route .
1. Injections :-
A ) .Intradermal :- Only Small Quantity Can Be Administered By This Route . (Raising A Bleb )
Bcg ,Vaccine Test For Allergy.
• Subcutaneous :- Here The Drug Is Deposited In The S.C Tissue. This Tissue Is
Less Vascular , Absorption Is Slow And The Drug
Long –Acting . It Is Reliable And Patient Can Be
Trained For Self –Administration . E g. -Insulin .
Drugs Can Be Administered Subcutaneously As :-
Implantation.
The Drug Is Packed In Sialistic
Tubes And Implanted Subcutaneously. The Drug
Gets Absorbed Over Months To Provide
Constant Blood Levels. The Empty
Non- Biodegradable Implant Has To Be Removed .
E.G. Hormones And Contraceptives .
C. Intramuscular :-
Aqueous Solution Of The Drug Is Injected In To
One Of The Large Skeletal Muscles. As The
Muscles Are Vascular , Absorption Is Rapid And
Quite . If The Drug Is Injected As An Oily solution
Or Suspension , The Absorption Is Slow . . Done at 12.07.24
D. Intravenous :- The Drug Is Injected Into
One Of The Superficial Veins That Is Directly
Reaches The Circulation And Is Immediately
Available For Action.
Drugs can be given IV as :-
- A bolus :- Where An Initial Large Dose Is Given.
The Drugs Is Dissolved In Suitable Amount Of
Injected Slowly ..
- Slowly :- Injected Iv Over 15-20 Minutes.
E.G – Aminophylline.
- Slow Infusion :-
Large Volume Have To Be Given Solution
Is Infused Over 3- To 4 Hours . But Rate Of
Infusion Depends On The Condition Of The
Patient. E.g. dextrose , saline.
2. Inhalation :-
Volatile Liquids And Gases Given By
Inhalation . These Inhaled Drugs And Vapors
May Act On The Pulmonary Epithelium And
Mucous Membranes Of The Respiratory Tract
And Are Also Absorbed Through These
Membranes .
3. Transdermal Route :-
Highly Lipid Soluble Drugs Can Be Applied
Over The Skin For Slow And Prolonged
Absorption . Inunction , adhesive units are
Some forms of transdermal drugs delivery .
inunction :- in this method of administration
The drugs is rubbed into the skin and it gets
Absorbed to produced systemic effect .
.
4. Transmucosal Route
The Drugs Are Absorbed
The Mucous Membranes . Transmucosal
Administration Includes Sublingual, Nasal ,Rectal
Routes .
A . Sublingual
the tablet or pellet containing the drug
Is placed under the tongue . It dissolves and
The drug is absorbed across the sublingual
Mucosa .
B . Nasal :-
drugs can be administered through
Nasal route either systemic absorption for
Local effects .
C . Rectal :-
Rectum Has A Rich Blood Supply And
Drugs Can Cross The Rectal Mucosa To Be
Absorbed For Systemic Effects . Some Irritant
Drugs Are Given Rectally As Suppositories .
3. local route ( topical ) :-
Drugs May Be Applied on The Skin
For Local Action As Ointment, Cream , Gel ,
Powder, Paste ,. Drugs May Also Be Applied On
The Mucous Membrane As In The Eyes , Ears ,
And Nose As Ointment ,Drops ,And Sprays.
done at 12.07.30.
• Pharmacokinetics :-
The study of the absorption ,distribution ,
Metabolism , and excretion of the drugs . All
These processes involve passage of the drug
Molecules across various barriers like the
Intestinal epithelium ,cell membrane , renal
Filtering membrane, capillary barrier and so on .
• Absorption
Absorption Is Defined As The Passage Of The
Drug From The Site Of Administration In To The
Circulation . For A Drug To Reach Its Site Of
Action, It Must Pass Through Various
Membranes Depending On The Route Of
Administration .Thus Except For Intravenous Route ,absorption is important for all other
Routes Of Administration . Several Factors
Influence The Rate And Extent Of Absorption Of
Drug . They Are :-
1 .Disintegration & Dissolution Time -
The Drug Taken Orally Should Break Up Into
Individual Particles To Be Absorbed . It Then Has
To Dissolve In The Gastrointestinal Fluids .
2. formulation
pharmaceutical preparations are
Formulated to produce desired absorption .
Inert substances used with drugs as diluents
Like starch and lactose may sometimes
Interfere with absorption .
3.Partical Size
Small Particle Size Is Important
For Better Absorption Of Drugs .
• Area And Vascularity Of The Absorbing Surface
The Larger The Area Of Absorbing
Surface And More The Vascularity Better Is The
Absorption .
• Metabolism
Some Drugs May Be Degraded In The Gi- Tract E.G . Insulin , Nitroglycerin .
Bioavailability :- the fraction of the drug
That reaches the systemic circulation following
Administration by any routes . Thus , for a drug
.
Given Iv ,The Bioavailability Is 100 % .On Im / Sc
Injection ,Drug Are Almost Completely Absorbed
While By Oral Route , Bioavailability May Be
Low Due To Incomplete Absorption .
12.07.31
2. Distribution
After Drug Reaches The
Systemic Circulation , It Gets Distributed To
To various tissues . It should cross several barriers
Before reaching the site of action .like absorption
, distribution also involves the same processes.
(filtration , diffusion , and specialized transport ) .
Various factors determine the rate and extent of
Distribution ,viz . ,lipid solubility ,ionization ,blood
Flow and binding to plasma proteins and
Proteins . Un Ionized Lipid Soluble Drugs Are
Widely Distributed Throughout The Body .
3. Metabolism
Metabolism or biotransformation is the process
Of biochemical alteration of the drug in the body.
Body treats
Most drugs as foreign substances and tries to
Inactivate and eliminate them by various
Biochemical reactions .these processes convert
the drugs in to more polar , water – soluble
Compounds so that they are easily excreted
Through the kidneys . Some drugs may be
Excreted largely unchanged in the urine . (frusemide , atenolol ) .
the most important organ of biotransformation site is the liver . But the
Drugs are also metabolized by the kidney ,
Gut mucosa , lungs , blood and skin .
excretion
drugs are excreted from the body
After being converted to water - soluble
Metabolites while some are directly eliminated
Without metabolism . The major organs of excretion
Are the kidneys ,the intestine , the biliary system
And the lungs . Drugs are also excreted in small
Amount s in the saliva , sweat and milk .
renal excretion
kidney is most important organ of drug excretion. The three processes involved in the
Elimination of drugs through kidneys are
Glomerular filtration , active tubular secretion
And passive tubular reabsorption .
Fecal And Biliary Excretion
unabsorbed portion of the orally
Administrated drugs are eliminated through the
Feces , liver transfers acids bases and unionized
Molecules in to bile by specific transport processes.
pulmonary excretion
the lungs are the main route of
Elimination for gases & volatile liquids VIZ
General anesthetics and alcohol .
other route of excretion
small amount of some drugs are
Eliminated through the sweat and saliva .
Saliva – metronidazole , phenytoin .
Sweat – rifampicin .
Drug Dosage
the branch of medical science which deals
With doses is called posology . (posos - how much: logos – science /study in Greek ) .
the therapeutic dose
Of a drug is the quantity of the drug needed to
Produce the therapeutic effect .
Maximum Dose
the largest dose of drug that can be
Safely given to a patient without producing
Harmful effects .
Toxic Dose
the dose of the drug which
Produces undesirable effects in majority of the
Patients .
Lethal dose
the dose of the drug which can cause death . ( phenobarbitone is 6 /10 gram).
minimum dose is the
Smallest dose required to produced a desired
Therapeutic effect of the drug .
Pharmacodynamics
Pharmacodynamics Is
The Study Of Action Of The Drugs On The Body
And Their Mechanisms Of Action . Drugs Produce
Their Effects By Interacting With The
Physiological System Of The Organisms . Drugs
May Increased Or Decrease The Secretion .
Thus Drugs Action By ;-
1. stimulation 2. Depression
3. Irritation 4. Replacement
5.anti infective or cytotoxic action
6. modification of the immune status
drugs may produce their effects by acting
Locally or systemically .
• Adverse Drug Reactions
• all drugs can produce unwanted
Effects . wHO has defined an adverse drug
Reaction as “ any response to a drug that is
Noxious and unintended and that occurs at dose
Used in man for prophylaxis , diagnosis , or
Therapy” . All drugs can cause adverse effects .
Some patients are more likely to develop adverse
Effects to drugs . Nurse should have a good
Knowledge about allergic reactions .
Side Effects
side effects are unwanted
Effects of a drug that are extensions of
Pharmacological effects and are seen with
Therapeutic dose of the drug . They are
Predictable , common and can occur in all
People . E. g . - hypoglycemia due to insulin .
Toxic Effects
toxic effects are seen with
Higher doses of the drug and can be serious .
• E. g - morphine causes respiratory depression
in over dosage .
Idiosyncrasy
Idiosyncrasy is a genetically
Determined abnormal reaction to a drug . E.g –
Primaquine and sulfonamides induce
Hemolysis in a patients with g6pd deficiency.
Allergic reactions
allergic reaction to drugs are
Immunologically –mediated reactions which are
Not related to the therapeutic effects of the
Drug . The drug or its metabolite acts as an
Antigen to induce antibody formation.
Subsequent exposure to the drug may result
In allergic reactions . This reactions are seen
Mainly on the target organs viz respiratory tract,
Gastrointestinal tract , blood and blood vessels .
Drug Dependence
drugs that influence the behavior
And mood are often misused to obtain their
Pleasurable effects . Repeated use of such drugs
Result in dependence . Drug dependence is a state
Of compulsive use of drugs though the person
Is aware of risks associated with its use.
Dependence could be psychological or physical
Dependence .
physical dependence is said to be present
When withdrawal of the drug produces adverse
Symptoms . Stopping the drug results in withdrawal
Syndrome . The symptoms of withdrawal syndrome
Are disturbing and the person then craves for the
Drug .
psycho logic dependence is compulsive drug
Seeking behavior to obtain its pleasurable effects .
Unit - 111
Weight And Measures Of Pharmaceutical
Preparations .
Weight
Weight Is A Measure Of The
Gravitational Force Acting On A Body And
Directly Proportional To Its Mass .
Measures
Here Measures Refer To The Measurement
Of Volume Of A Drug .
There are two systems used in weight and
Measures .
1. Metric System .
2. Imperial System .
1. Metric System
This Is The International System Of Weight
And Measures based on meter and gram so
Now including these 6 primary units is also called
S. I. System . It is based on decimal system .
Metric system are simpler , easier and more
Accurate to use . The standard unit of measuring
Weight is kilogram (Kg) and measuring the
Capacity is liter (l) .
units of weight
1 kilogram ( kg ) = 1000 g
1 hectogram ( hg) =100g
1decagram ( dag ) =10g
1miligram ( mg ) =0.001g ( 1mg )
1centigram (cg ) = 10 mg
Units of capacity
1 liter (l) =1000ml
Domestic measures
these measures are used to the
Doses of liquids at home .there is a lot of
Variation in the size of the domestic measures
Used .
common domestic measures :-
1 teaspoonful = 4 ml
1 tablespoonful = 15 ml
1 teacupful =120 ml
1 ml = 16 drops
1 drop = 1 minim
1 tumblerful =240 ml
Imperial System
This system is an old system and is based on
Units which are not related .it is complicated
To follow and therefore not the preferred
System . The imperial standard is pound .
Imperial system is divided to 2 type.
1 . Avoirdupois system
2. Apothecaries system
Measures of capacity in imperial system .
the standard unit of capacity is gallon . This is
The same for avoirdupois and apothecaries
System .
1 gallon =160 fluid ounce
1/ 8th of gallon = 1 pint / 20 fluid ounces
1/ 60th of gallon = 1 fluid ounce
1/ 8th of fl ounce = 1 fluid drachm
Avoirdupois system
The Standard Unit Of This System is pound.
1 pound lb equivalent 16 Oz
1 ounce oz --- 437.5 grains
--------------------------------------------------
1/ 60th of fl drachm = 1 minim
1fluid ounce =480 minims .
Apothecaries System :-
this is also known as troy system and the
Standard weight is grain .
20 grains = 1 scruple
60 grains = 1 drachm
480 grains = 1 ounce /1 troy ounce
12 troy = 1pound
Pound lb Libra
Measures of capacity.
Minim m minimum
Pint o octavius
Abbreviations used in apothecaries system .
Eng; abbreviator Latin name
Grain gr Granum
Scruple € scrupulus
Drachm ³ Drachma
Ounce (avoirdu) oz uncia
Ounce (apothe) uncia
Pound lb libra
Minim m miimum
Fl. drachm fluidrachma
Fl.ounce fluidruncia
Pint o octarius
Galoon c congius
Conversion from imperial to metric system
1 grain = 65mg(64.8)mg
1drop =1 minim (0.06 ml)
1 fl .ounce = 30 ml
1gram = 15gr
1 ml =16 minim
1mg =1/65 gr
1liter = 33.8 fl.ounce
Percentage solution and calculation
percentage solution are 2 type :-
1. weight in volume (w/v) solution
formula :- 1% w/v solution means
solid- 1 part by weight is dissolved in
Solvent enough to produce 100 parts by volume
Of the solution . To the dissolve the solid in part
Of the solvent and adjust the volume to 100ml.
2.volume by volume solutions
the formula -- 1% v/ v solutions
solute 1 part by volume.
solvent to produce 100 parts by volume .
this means 1 ml of solute is dissolved in
sufficient amount of solvent to produce 100 ml
Of the solutio
1.calculate the quantity of sodium chloride
Required for 500ml of 5% solution .
1% w/v solution = 1g of NACL in 100ml water .
5% solution =5g in 100mlwater .
for500ml of 5% qu.req.nacl = 5/100 500
Quantity of required nacl =25 g.
Percentage means number of g in 100 ml
2.What is the percentage of nacl in a solution that
Contains 25mg of nacl in 50ml of the solution ?.
percentage = 25/ 50 100 = 50%.
3. How much of insulin(In ml) would you draw if
24 units of insulin is required .Supplied to vial of
insulin u-40.
received insulin 1ml = 40 unit.
the insulin syringe has 1ml in 10 division.
; insulin syringe 1ml =10 division
insulin 40 unit (in 1ml ) =10 div (In syringes)
to be draw 24 units = 10 / 40 24
= 6 division.
Insulin should be drawn up to 6 divisions to get
24 units .
Patient requires 12 units of plain insulin and
32 units of lente insulin. 40 u strength of both
Vial are available. calculate the dose of each type
Of insulin?.
1ml/40 u in 10 division
1 u =10/ 40 division
12 u =10/ 40 12 =3 div (0.3ml).
40 u =10 div
32 u =10/40 32 =8 div (0.8ml)
Lente insulin should be drawn up to 8 divi
to get 32 u .
preparation of dilute solution from concentrated
Solutions :- at.9.17
some drug are dispensed as
Concentrated solutions so that it is easy to
Transport. Antiseptics and disinfectants are
Generally supplied as strong solutions .
Generally for such solutions , strength are
Mentioned as parts (1: 100) which means parts
Of dissolved substance in parts of the solution.
Weight of solid (in grams ) is dissolved in
Volume (in ml) of the solution.
Quantity of the concentrated stock solution
Required can be calculated using a simple formula.
A = D/ H Q
A--- amount of the stock solution needed for
preparation .
D--- desired strength
H---- strength of solution available at hand .
Q--- quantity of solution to be prepared.
1. find the amount of 10 % Nacl required to
make 5000ml of 2% solution .
des. Strength =2%
str. In hand =10%
quanti. Required =5000ml
A =D / H × Q
A =0.02 /0.1 × 5000
A =1000ml
1000ml of 10% Nacl is mixed with 4000ml of
Water to form 5000ml of 2% solution .
2. A stock solution of 1 in 1000 candy's lotion
Is given make 5 pints of 1 In 5000 candy's lotion ?
des. Strength =1 in 5000
St . In hand = 1 in 1000
quan . Required = 5 pints
Amount of stock solution = ?
A =D /H × Q
= (1 /5000) / ( 1/ 1000 ) × 5
=1 pint
Take 1 pint of candy's lotion ( 1 in 1000 )and add
4 pint of water to make 1: 5000 candy's lotion.
calculation of pediatric dosage .
drugs are generally dispensed In adult
Dose .some formula are available for the
Calculation of dosage for children from adult
Dose .
1. Young's formula
this formula considers age In years and can be
Used for children from 1 to 12 years of age.
child dose = age of child (year) × adult dose
-------------------------------------------------- --- age of the child (year ) + 12
Adult dose of a drug is 500mg . Calculate the dose
Of the drug for 3 years old child .
Child dose =3 / ( 3+ 12) × 500
child dose =3 /15 × 500
=100mg of the drug is needed
For 3 years old child .
2. Clarks Formula
Clarks formula considers weight of the
child .
child dose =weight of child in pound × A. Dose
; --------------------------------------------------
150
If the adult dose of drug is 750 mg. calculate the
Dose for a child weight in 20 lb .
child dose = 20 / 150 × 750
=100 mg .
3. Fried's formula
This formula is useful for calculation of dose
In children under 1years of age.
CH. Dose = age of the child (in months ) × A.D.
… ---------------------------------------
150
If the adult dose of a drug is 250 mg. calculate
The amount of drug for an infant of 5 month.
A = 5 / 150 × 250 mg
= 8.3 mg.
Pharmaceutical preparations
drugs may be dispensed in different
Dosage forms for convenience of the patient .it
Is essential to know the different preparations
and their advantages and disadvantages in order
To use them correctly .drugs may be dispensed
As solid or liquids .
solids
Drugs may be conveniently administrated in
Solid dosage forms as powders , tablets , capsules,
Pills .
powders12.9.21
powders are solid medicaments in
Finally divided form .powders may be internal
use ,external use .
Powders may be classified as:-
simple powder
powders in cachets and capsules
dusting powder , insufflations .
simple powder :-
contain a single ingredient while
Compound powders contain more than one
Ingredient . Powders may be filled in capsules
For oral administration.
cachets
cachets are solid dosage form In which
The drug is enclosed In a sheet of wafer made of
Rice powder and water . Cachets are also called
Wafer capsules . They have certain advantages of
Easy to prepare and quickly dissolved in the
Stomach .
capsules
Capsules are cylindrical shells containing the
Drug . Two type of capsules can be made hard –
And soft capsules .hard capsules are cylindrical
In shape and contain solid medicaments . Soft
Capsules May contain solids , liquids , or semi
Liquid and may be cylindrical or spherical shape.
Dusting powder
dusting powders are meant for
External use . They are two types .
1. medical 2. surgical
medical dusting powders are used on superficial
Skin conditions and are not meant for systematic
Absorption .
surgical dusting powder are used on
Wounds and body cavities .they should be
Sterile as they may be absorbed . These are
Usually antibiotics .
insufflations
insufflations are dusting powders
Which are blown with the help of an insufflators
Into areas like nose or ear .
Dry syrup
dry syrups are also powders which are
To be made in to solution before use .drugs which
Are not stable in solution are dispensed as dry
Syrups .many antibiotics including amoxicillin,
Cephalexin ,.
Tablets
tablets are flat circular discs which are
The most commonly used solid dosage forms .
Powders are moulded or compressed in to tablets
. The drug is mixed with an inert substance
Like lactose , sucrose , are meant to dissolve
Quickly in the stomach fluids .
Tablets and capsules may be available in 2 forms.
1. strips :-
tablets are packed in strips or blister packs
.these are safer ,attractive ,and more hygienic .
2. loose :-
a large number is counted and given to
The patient .the nurses hands should be clean .
Moreover these can cause allergic reaction in nurse
And pharmacist who are handling them.
Pills
pills are made by mixing powdered drugs
With an adhesive substance like glucose or
Honey .they are flattened sphere or may be
Globular or oval in shape .
lozenges
solid preparations made of sugar and gum
.lozenges are used for their local action on the
Mouth and throat .they need to dissolved
Slowly so that have a prolonged local action
And therefore they are hard . ( Vicks , strepsils ).
Solid for insertion into body cavities :-
suppositories are ovoid shaped solid
Preparations meant for insertion in to the rectum
.it may be
1.for a local effect ,e.g. - local anesthetic for
Piles. Prednisolone for ulcerative colitis .
2.for systemic absorption e.g.- aminophylline .
3. for evacuation of the bowel - dulcolax .
pessaries :-
pessaries are cone shaped solid dosage
Forms meant for insertion into the vagina for
Local action .( candid pessaries , betadine pessaries
liquids
many pharmaceutical preparations are
Dispensed as liquids . Solutions , mixtures, elixirs ,
Syrup ,etc are liquids. Emulsion and suspension
Are also available .
solutions:-
Solutions are liquid dosage forms prepared by
Dissolving a solute in a solvent .a solutions is
Homogeneous , and may be used orally or applied
Externally .
Advantages Of Solutions :-
1. the dose can be adjusted as required .
2. the solution can be made attractive by colors
Flavors and sweetening agents .
3.easy to swallow for children and elderly patients who are unable to swallow .
4. they can easily be absorbed because they are
are in liquid forms .
Disadvantages :-
1. difficult to carry liquids . ( Done at12.10.05)
2. liquids are less stable than solid dosage forms.
3. it is difficult to the unpleasant taste and odor
of some drugs .
4. a spoon or measuring cup is needed for
Administration .
Mixtures:-
A Mixtures Is A Liquid
Preparation Containing Two Or More Substances
Meant For Oral Use . A Single Dose Mixture Is
Called Draught .Mixtures Are Prepared Fresh And
Dispensed . They Do Not Generally Have Long
Shelf – Life (Not More Than 30 Days .
Elixirs :-
Elixirs are clear ,palatable , flavored liquid
Preparation for oral use. They may be colored to
Make them attractive and generally are more
Stable and have a longer shelf life .
E.g. Ephedrine elixir
Syrup
syrups are flavoured , concentrated, viscous
Solutions of sucrose or other sugars .syrups
Containing a medicinal substance is medicated
While flavouring syrup contain a pleasant flavour .
E.g. Orange syrup.
cough syrup ,antihistamine syrup .
linctuses :-
linctuses are sweet viscous liquids. They
Contain a syrup and may also have glycerin as a
Vehicle which has demulcent effects on the
Mucous membrane of the throat . Cough remedies
Are available as linctuses . E.g. linctuses codiene.
Drops :-
drops are liquid preparations which may be used
Orally or for local effect like eye drops, nasal
Drops , and ear drops. Oral drops are used in
Children .( vitamin syrup ,paracetamol syrup).
These preparations are provided with droppers.
Liquids for external application:-
liniments:-
liniments are liquid or semi liquid
Preparations meant for application to the skin
With fraction . Liniments may contain ingredients
Which are irritants . Therefore liniment should
Not be applied on the broken skin. (turpentine
Liniment ,metylsalicylate liniment ).
lotion :-
Lotions are liquid or semi liquid preparations
Meant for external application .they have soothing
And protective effect . They are applied for their
Local effect . ( calamine lotion .).
other preparations:-
1.suspensions :-
suspensions are liquid dosage forms
Containing finely divided solid particles. Drugs
Are generally dispensed as suspensions for oral
Use , but they may also be available for topical
Application .some drugs are available as dry
Powder .on mixing with required amount of water
And shaking thoroughly ,a suspension is formed
. E.g cotrimoxazole suspension .
2. Emulsions
emulsions are liquid preparations containing
Two immiscible liquid made miscible with the
Help on an emulsifying agent .drugs meant for
Oral use or external application maybe dispensed
As emulsions .( shark liver oil emulsion ).
semi solid dosage forms :-
1.ointments
ointments are semisolid preparations
Meant for external application.tehy contain a
A greasy base . E.g Whitfield's ointment .
Ointment may be meant for local action or
For systemic absorption in to the layers of the skin.
Creams :-
creams are similar ointments but contain
Water soluble base because of which they can
Be clean easily from the skin .---- cetrimide
Cream, silver sulphadiazine cream .
gels /jellies :-
gels are thin transparent or translucent
Preparations meant for external application .
They are non-greasy ,jelly- like in consistency and
Are applied on the skin or mucus membrane .
Diclofenac gel , daktarin gel .
liquids used for action in the mouth :-
Gargles:-
gargles are aqueous solutions used for
Deodorant effect or to treat infections in the
Oral cavity .---- astringents ,anti septic, and
Flavouring agents are used in gargles .---
Phenol gargle ,potassium chlorate and phenol
Gargle .
mouth washes ;-
mouth wash are liquids used to
Cleanse and i deodorize the oral cavity .they
Generally contain antiseptics or astringents .
Liquids to be instilled in to body cavities ;-
Douche ;- a douche is an aqueous solution used
For rinsing body cavity .though the word douce
Is used for vaginal solutions .it can also be used
For solutions meant for irrigation of the bladder
Or the rectum .all these solution can also be
Called irrigations .
cleansing douche – isotonic sodium chloride sol.
Chlorhexidine douche – antiseptic .
Enema :-
Is a liquid preparation meant for introduction in
To rectum.
Additives
substances other than the active principle
Used in a pharmaceutical preparation are additives
. Additives have no pharmacological actions but
But are used for certain purpose . These are
Included to :-
1.Surfactants 2. coloring agents
3.Flavoring agents 4. sweetening agent
5.Pressavatives 6. vehicles
1. Surfactants :- (surface active agents).
Surfactants are substances which lower the
interfacial tension between two phases of liquids.
Thus two immiscible liquids are made miscible
With the help of surfactants .they are the most
Commonly used additives in both liquid and
Solid preparations . Surfactants maybe used as
Detergents ,wetting agents , emulsifying agents .
e.g glycerin monosterate( non-toxic surfactant).,
sodium lauryl sulphate .
2. Coloring agents :-
coloring agents are substances
Used to impart color to drugs and food .coloring
Agents may be used in pharmaceutical
Preparations .
• To make them more attractive and increased
their acceptability .
bright colors like orange red , cherry red, etc.
3. Flavouring agents :-
Flavouring agents are substances used to impart
A pleasant smell and taste to the preparation
So that it is more palatable . Generally fruity and
Spicy flavours are used for orally used
Preparations while flowery flavours are used
For preparations applied topically. – menthol ,
Chloroform spirit , aldehydes , esters .
Sweetening agents :-
sweetening agents are substances used to
Impart a sweet taste to a pharmaceutical
Preparation in order to mask its unpleasant
Taste .– sucrose , fructose ,.
preservatives :-
preservatives are substances added
Pharmaceutical preparations to prevent the
Growth of micro organisms in it. Certain
Ingredients like water and sugars encourage the
Growth of bacteria and fungi .an ideal
Preservatives should be non-toxic , be effective
Against all the micro organisms like to
Contaminate . --- phenol , benzalkonium chloride
,alcohol .
,
Vehicle :-
vehicle is a medium in which the ingredients
Are the dissolved or suspended. For liquid
Formulations , we use the word vehicle while for
Semisolid preparations like ointments .
Water is the most commonly used vehicle .
Common abbreviations in use
Latin Term Abbreviation English Meaning
1.Ad ad to,
2.Ana aa of each
3. Ante a before
4. Ante cibos ac before meals
5. Aqua aq water
6.Aqua destillata aq dest distilled water
7.Auris dextra a.d. Right ear
8. Auris laeva a.l. Left ear
9.Auristillae auristill ear drops
10.Bis in die bid twice a day
11.Capsula caps capsule
12.Cum c with
13. E.lacte e.lact with milk
14. Grana gr a grain
16. Gutta /guttae gtt a drop ,drops
17 .Hora h an hour
18 . Hora somni hs at bed time
19.Inter cibos ic during meals
20.In dies in.d daily .
21. Injectio inj an injection.
• Laevo l left.
• Linimentum lin a liniment.
25.Liqour liq solution
26.Lotio lot. Lotion .
27. Mane m morning
28 .Mistura mist a mixture
29 .Modo Prescripto m .pres as prescribed
30 .Nebula nebul a spray
31.Octarious o a pint
32. Oculo utro o u each eye
33. Oculus dexter od right eye
34.Oculus leavus ol left eye
• Omni omn every
• Omni mane om every morning
• Omni nocte on every night
• Oris ,Os os mouth
• Per os po orally, by mouth
• Post cibos pc after meals
41. Post cibos pc after meals
42 Pro re nata prn when necessary .
43. Pulvis pulv powder
44.Quaque quarta hora qqh every fourth hour
45. Quarter in die qid four times a day
46. Quotidie quot daily
47. Recipe Rx take
48 . Semis ,Semi ss half
49 .Sext is horis sext .hor every six hour
50 .Si opus sit sos if necessary
52 .Statim stat immediately, at once
53.Tabella,tabeltta tab a tablet .
54. Ter in die tid three times a day
55. Unguentum ung an ointment
57. Unus i one
58. Duo ii two
59. Tres iii three
60 .Quatuor iv four
61. Quinque v five
62. Sex vi
63. Septem vii
64 . Octo viii
65 . Novem ix
66. Decem x
67 .Undecim xi
68. Quindecim xv fifteen
69. Tea spoon tsp tea spoon full
70.Tabl spoon tbsp table spoon full
71. Quaque hora qh every hour
Unit -1V
Explain The Actions Of Drugs By Each
Classification :-
Drugs can be classified from different
Perspectives .for example :-
1. drugs may be classified by body system
-----drugs that affect the respiratory system,
-----drugs that affect cardio vascular system.
• Drugs May Be Classified By The Symptoms
Relieved Of The Drug Or Clinical Indication of
The drug ------
-- Analgesics , Antibiotics
nurses categorize medications
With similar characteristics by their class .drug
Classification indicates the effect on body
System , the symptoms relived , or the desired
Effect . Each class contains drugs prescribed for
Similar types health problems . The class is not
Necessary same. A drug may also belong to
More than one class . E.g .- aspirin is an
Analgesics , an antipyretic and anti-inflammatory
Drugs.
nurses should know the general characteristic
Of drugs in each class .each class has nursing
Implications for proper administration and
Monitoring . E.g. Nursing implication related to
Diuretic administration include monitoring intake
And output , weighing the client duly ,assessing
The development edema in body tissues , and
Monitoring serum electrolyze level . Nursing
Implications of all medications within a class
Provide guidelines for safe and effective care .
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