ORIENTATION
TEAM
Lecture 6
Clinical Pharmacy
/Clinical2020CU
Cairo University
2014/2015
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Chapter 5
*Remember from the first lecture :
-Orientation : The act of orienting or the state of being oriented . An adjustment or
adaptation to a new environment , situation , custom or set of ideas .
-Pharmaceutics : The science of dosage form design .
-In this lecture you suppose to know :

Information Resources

Use of computer in pharmacy

Dosage forms
1] Dosage Forms
:
-The gross physical form in which the drug is used by the patient
-The means through which drug molecules reach the target site inside the body to give
their actions
*Target Site:
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Drug Action
Systemic
Local
-The drug acts in the whole body
-The drug only acts in the
era where it is administered
Absorbtion
Tissue
Site of action
Plasma Water
Metabolism
Excretion
*Route of administration (location of drug application ) :
-The United States Food and Drug Administration recognizes 111 distinct routes of
administration.
Into
Enteral
Onto
Parenteral
Topical
Oral & Rectal
Injection
Dermal & Occular
Buccal
Transdermal
Vaginal & Nasal
Sublingual
Inhalation
Auditory & Urethral
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1] Oral po (from the latin per os )
Swallowed
First pass effect
*Advantages:
•Most convenient for the patient (chronic disease). -Non invasive -Ease and safety of
administration -No sterile procedures required
•Possibility of controlled release delivery
*Disadvantages:
•First pass metabolism
•Not for drugs inactivated by GIT
•Not for drugs irritant to the GIT
•Not for patients with unconsciousness, vomiting, malabsorption or surgery
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Oral transmucosal
Buccal
Sublingual
Not Swallowed
Parentral
Oral
Rest of the Body
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*Advantages:
•Rapid transport to the systemic circulation
•No first pass hepatic metabolism
•Non invasive
•Possibility of controlled release delivery (buccal)
*Disadvantages:
•Some drugs can not pass the mucosa (permeation enhancers)
•Not for bitter drugs
•Some drugs are irritant to the mucosa
•Eating and drinking may be restricted
•Possibility of the patient to swallow the dosage form
Rectal
*Advantages:
•Suitable for unconscious patients
•Suitable for patients with vomiting
•Suitable for drugs irritant to the GIT
•Most of the absorbed drug by-passes the first pass metabolism
*Disadvantages:
• Less convenient
• Small absorption surface area
•Not for patients suffering from diarrhea
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Injections
Primary Routes
Intravenous
Specialized Routs
Intramuscular (I.M)
Subcutaneous (S.C)
(I.V)
Made into the striated muscle
-Made into a vein
(introduced directly into
the blood stream)
fibers that lie beneath
the subcutaneous layer
Made under the skin,
into the
subcutaneous
tissue
Intravenous
injection
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Intramuscular
injection
Subcutaneous injection
Side of the Arm
Back of the Arm
Abdomen
Front of the thigh
*Specialized Routes :

Intradermal (I.D)

Intra-arterial (I.A)

Intraocular

Intra-Abdominal

Intracardiac

Intraventricular

Intraspinal
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*Advantages:
•Rapid onset of action
•100% absorption
•No first pass hepatic metabolism
•Possibility of controlled release delivery (eg. IM and SC)
•For patients with unconsciousness, vomiting or post surgery
•For drugs not absorbed, deactivated or harmful to the GIT
*Disadvantages:
•Invasive
•Strict antiseptic techniques are required
•Not for self administration
•Not convenient for the patient, painful
•Possibility of complications (embolism, phlebitis, infection …)
•No antidote.
Transdermal
Drug is applied to the skin and absorbed through its layers
*Advantages:
•Rapid transport to the systemic circulation
•No first pass hepatic metabolism
•Non invasive
•Possibility of controlled release delivery
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*Disadvantages:
•Not all drugs can be absorbed transdermally
•Transdermal absorption is much poor than intestinal absorption.
•More expensive
•More difficult to manufacture
Inhalation
drug is taken by nose or mouth and deeply inhaled into the lungs
*Advantages:
•Rapid absorption (high blood flow and large surface area of the alveoli)
•Rapid onset of action.
•No first pass effect.
*Disadvantages:
•Special apparatus is required.
•Irritation of the respiratory tract may take place.
•Cooperation of the patient is required.
Topical
Dermal
Occular
Vaginal
Nasal
Auditory
Urethral
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*Factors affecting the choice of route of administration :
1.Ease of administration
2.Desired onset (rapid, slow)
3.Duration of action (short, prolonged)
4.Duration of drug use (acute, chronic)
5.Site of therapeutic action
6.Quantity of drug to be administered
7.Drug characteristics (taste, stability, metabolism, excretion and toxicity).
8.Status of patient (post surgery, comatose, co-operative, …)
9.Age of the patient
10.Setting where drug is administered (home, hospital, …)
ORIENTATION TEAM
GOOD LUCK :)
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