PHARMACOLOGY - ROUTES OF ADMINISTRATION OF DRUGS

1.  SUB : FUNDAMENTALS OF NURSING
 UNIT : VIII PHARMACOLOGY
 TOPIC : ROUTES OF DRUG ADMINISTRATION
PRESENTED BY
 P.THIRUNAGALINGA PANDIYAN
M.Sc.,(N) D.Pharm.,

2.  1 Enteral
 2 Parenteral
 3 Inhalation
 4 Topical or Local

3. 1. ENTERAL
 Oral
 Oral route is the
most common route
of administration.
 It is safe, convenient,
and cheap and does
not require the
services of skilled
personnel.

4.  Sublingual
 The tablet is placed
under the tongue
and absorption
form oral mucosa is
rapid and uniform.
 This route has
special importance
for certain drugs.
 Eg : Nitroglycerin

5.  Rectal Administration
 The drug may be
given rectally for
systemic effect when
the patient is either
unconscious or
vomiting.
 The drugs
administered rectally
are in the form of
suppositories and
enema

6.  PARENTERAL (Par-beyond enteral-intestine)
 The term parenteral administration
implies the routes through which the drug
directly reaches the body fluids.
 The Parenteral administration has certain
advantages over oral route.
 Drug is neither invaded nor destroyed by
digestive enzymes.

7.  Subcutaneous:-
 The drug is dissolved in a small volume of
vehicle and injected beneath the skin from
where the absorption is slow and uniform.
 This method is particularly useful when
continuous presence of the drug in the
tissues is needed over a long period.
 e.g. insulin.

8.  Intramuscular
 Injection is made deep into the muscle tissue.
 In humans, the best site is deltoid muscle in
the shoulder or the gluteus muscle in the
buttocks.

9.  Intravenous:-
 Drug solution in injected directly into the
lumen of a vein so that it is diluted in the
venous blood.
 The drug is carried to the Heart and
circulated to the tissues.

10.  Intraperitoneal
 The peritoneum offers a large absorbing
surface area from which drugs enter
circulation rapidly but primarily by way of
portal vein. Hence First-Pass effect not
avoided

11.  Intradermal
 Drug are injected into papillary layer of skin.
For example tuberculin injection for montoux
test and BCG vaccination

12.  Intra Medullary
 The drug is introduced into marrow cavity
 This route is used when veins are not
available specially in children.
 In adults the injection is made into marrow
cavity of sternum and under 3 years of age
into that of tibia or femur.

13.  Intrathecal
 Introduction of injection into spinal is called
as intrathecal
 The injection of local anaesthetics for the
induction of spinal anaesthesia is given by
this route.

14.  Intra articular
 It is also known as intra synovial.
 Sometimes drugs are injected into the joint
cavity to localize their action at the site of
administration e.g. Hydrocortisone acetate in
the treatment of rheumatoid arthritis.

15.  Intra Cardiac
 In cardiac arrest intra cardiac injection of
adrenaline is made for resuscitation.

16.  Intra-arterial
 Sometimes a drug is injected directly into
an artery to localize its effects in a particular
tissue or organ.

17.  Inhalation
 Inhalation or Pulmonary Absorption: Gaseous
and volatile drugs may be inhaled.
 They are then absorbed by pulmonary
endothelium and mucous membrane of the
respiratory tract and reach circulation rapidly.

18.  Local or Topical Application
 Skin : Drugs applied locally on the skin are
poorly absorbed through the epidermis.
 Inunctions – It is rubbing the drug on the skin
 Mucous Membranes: Drugs are applied onto
the various mucous membranes for their local
action.

19.  Preparation for local application
 Bougie for urethra
 Pessary for vagina
 Suppository for vagina and rectum
 Enema for rectum