Therapeutic alternatives:
 These are drug products that contain different
active ingredients but of the same pharmacologic
class and used for the same therapeutic objective.
e.g.1 Diclofenac-containing drug products could
be
used
instead
of
those
containing
Indomethacin or Ibuprufen (as NSAI).
e.g.2
Naphazoline
Phenylephrine
vasoconstrictors).
hydrochloride
hydrocholride
and
(as
Routes of administration
 The majority of drugs must be absorbed into
bloodstream in order to reach the site of action.
 They affect the rate and efficiency of absorption.
 A particular drug may be available in different
forms.
 Many drugs are available as tablets and injection.
 The
choice
between
tablets
and
injection
depends on a number of factors including:
1) The severity of illness.
2) The urgency with which the drug effect is
needed
3) The part of the body requiring treatment.
4) The patient’ s general state of health (ability to
swallow).
Oral administration
 Is
the
most
frequently
used
method
of
administration.
 Most drugs are absorbed into bloodstream
through the walls of the intestine.
Advantages:
Safe, easy and economic.
Disadvantages:
Unsuitable in certain medical conditions and for
some drugs such as:
1) Emergency due to slow onset of action
2) Presence of nausea, vomiting and diarrhea.
3) Drugs destroyed by gastric acid e.g. Penicillin.
4) Drugs destroyed by GIT enzymes e.g. Insulin.
5) Drugs inactivated by first pass metabolism in
the intestinal mucosa e.g. Nitroglycerin.
6) Drugs that interact with food e.g. Tetracycline.
7) Swallowing difficulty:

Unconscious patients
 Children refuse to swallow oral medications
 Geriatrics often have difficulty in swallowing
Sublingual administration
The drug is inserted under the
tongue in the form of tablet.
Advantages:
1) Rapid onset of action (less than 5 minutes).
2) Suitable for drugs subjected to first pass
mechanism e.g. Nitroglycerine.
Disadvantages:
1) Short duration of action (the length of time that
a drug gives a therapeutic effect).
2) Unsuitable for irritant drugs and drugs with
bitter taste.
Parenteral administration
Drugs may be injected into body to produce
systemic effect.
Advantages:
1) Rapid response.
2) Lower dose and side effects.
3) Person’s intolerance to a drug when taken by
mouth (irritant drug).
4) Suitable for drugs destroyed by gastric acid.
5) Suitable for drugs with poor GIT absorption.
Disadvantages:
1) Dangerous as it is difficult to remove the drug
once it is administrated.
2) Invasive and painful (lower compliance).
3) Sterile techniques are necessary to avoid the risk
of infection.
4) Need special experience.
Types of injections
Types of injections:
 Intravenous (IV)
 Intramuscular (IM)
 Subcutaneous (SC)
 Intradermal (ID)
The type of injection used depend on:
1) The nature of drug
2) The condition being treated.
Intravenous route
Administration and precautions:
 Are usually made into a peripheral vein with an
angle of 15-20o.
 A danger for IV rout is the introduction into toxic
agents
or
microorganisms
directly
into
bloodstream.
 Solution must be sterile and free of particles or air
bubbles (embolism).
Intramuscular injection
Administration and precautions:
 Slower onset of action and longer duration
(depot effect) compared to IV route.
 Are given in the upper outer portion of the iliac
muscle (avoid nerve insertion).
 Injection is administered with 90 o angle.
 Volume of injection up to 5 mL.
Subcutaneous injection
Administration and precautions:
 Longer duration of action compared to IV and IM
 Is given below the skin into the subcutaneous fat
(45o angle).
 Usually on the outside of the upper arm, may also
in the abdomen.
 No more than 1.5 mL should be injected.
 Common example is insulin.
Intradermal injection
Administration and precautions:
 Administered into the capillary rich dermis (10-15o
angle).
 Used for local anesthesia.
 The major use is allergy skin testing.
Rectal administration
Drugs are administrated into the rectum in the
from of suppositories or retention enema.
Advantages:
1) Rapid onset of action.
2) Suitable for drugs destroyed by gastric acid.
3) Drugs subjected to first pass metabolism.
4) Suitable in case of nausea, vomiting and coma.
Disadvantages:
Irregular absorption.
Inhalation
 Drugs may be inhaled to produce a systemic effect
or a local effect on the respiratory tract.
 Drugs are gases or volatile liquids.
Advantages:
1) Rapid onset of action.
2) Can be used for a local effect on the lungs e.g.
bronchodilator in asthma and bronchitis.
or for a systemic effect e.g. inhalation general
anesthetics.
Topical administration
 The drug is applied to the skin or mucous
membranes.
 Used in treating localized disorders such as skin
infections and nasal congestion.
 Available in a variety of forms such as creams,
lotions and eye and ear drops.
Advantages:
 It is easier to control the effects of drugs applied
locally and to produce the maximum benefit with
minimum side effects.
Disadvantages:
 Slow onset of action.
Slow-release preparations
 They are formulated to release their active drug
slowly over a given period of time.
 Used when it is necessary to control the release of
small amounts of drug into body.
 Present
in
transdermal
capsules.
the
form
patches,
of
depot
implants,
injections,
tablets
and