5. Oral route of drug Administration
Advantages:
1.Safest and most economical
2.This route is the most convenient route of drug
administration
3.Patients can take the prescribed medicines
himself
4.There is no pain to the patient, this route is
very convenient and economical
e.g-Tablets, capsules, mixtures, emulsions,
suspensions.
6. Oral route of drug Administration
Disadvantages:
1.The effect of drug taken by oral route is delayed
2.This is not an emergency route
3.The irritant drugs cannot be given through this
route
4.This route cannot be used in case of
unconscious and non-cooperative patients
7. Oral route of drug Administration
Disadvantages:
5. Certain drugs cannot be given through this
route as they are destroyed by gastric enzymes.
6. Objectional odour and taste
7. Damage or discoloration of teeth
8. Sublingual route of drug Administration
• Advantages:
• Onset of action is quick
• The overdose of drug is avoided
• The drug is not destroyed by stomach enzyme,
metabolic destruction in the liver is prevented .
• Patients must be instructed not to swallow the tablet
and water should not be taken immediately after the
tablet to ensure proper sublingual or buccal absorption.
9. Sublingual route of drug Administration
• The tablets are placed under the tongue sucked.
• Some drugs like isoprenaline and nitro-glycerine may
be given by placing them under the patients tongue,
where they are retained until dissolved and absorbed
or the desired effect is produced.
10. Parenteral route of drug Administration
• Parenteral route refers to any route other than
gastrointestinal route (Enteral)
• These routes are selected-
– when the drug is poorly absorbed from the gut, or
– Inactivated by digestive enzymes, or metabolized
during its first passage through the liver
– Or if the patient is unable to tolerate or take oral
medications
– Or if rapid effect is desired
11. • The drug is injected into the outer layer of the skin
• The amount of drug is given in small quantity and
absorption is slow The medial surface of forearm is the
site frequently used.
• This test is mainly used for diagnostic test like shick test
for diphtheria ,tuberculine test
• Local anaesthetics are first injected intradermally and
then further deeper injections are made. Also used for
allergic sensitization testing in patients.
Intradermal Route:
13. • The injection is made into loose subcutaneous
tissue under the skin. The common sites are upper
arm, abdomen and front of thigh
• The drug absorption is slower and the action is
longer than IV or IM.
• Drugs like adrenaline, morphine and insulin are
usually administered subcutaneously
Subcutaneous route:
15. • The injections is given with the longer and heavier
needle that penetrates the subcutaneous tissues and the
drug is deposited deep between the layers of the
muscle mass.
• This route is suitable for administration of solutions or
suspensions
• Muscles are more vascular and less sensitive to than
subcutaneous injection sites.
Intramuscular route:
16. • Absorption is faster and rapid
• Small volume up to 3ml are injected into deltoid
muscles.
• Small or large volume are injected into gluteal mass
underlying the upper and outer quadrant of the left or
right buttock. Drugs like sex hormones,
corticosteroids, procaine penicillin G.
Intramuscular route:
17. • When an immediate effect is desired
• It may be introduced directly into a vein as an injection
or infusion.
• The cubital vein at the bend of elbow is selected or
superior longitudinal sinus in children may be selected
• IV injection require small amount of solution
referred as bolus, are given by means of syringe
Intravenous route:
18. • An infusion is the IV administration of larger amounts
of fluid varying from 1 to 2 litres.
• Infusion are mostly given-
• to relieve tissue dehydration,
• to restore depleted blood volume,
• to dilute toxic substances in the
blood and tissues, to supply
electrolytes, drugs and foods.
Intravenous route:
20. • Also designated as bone marrow injection and the
material is injected to the bone marrow of the sternum or
tibia. This route is used when the veins are not available,
specially in childrens.
• Whole blood ,normal saline or glucose may be
administered by this route.
Intramedullary injection:
21. • Needle is placed in an artery, through which an arterial blood
sample may be withdrawn for blood gas studies or a radio-
opaque substance may be injected to make arteries of the part
visible on an X-ray film (Arteriography)
• Certain cytotoxic drug may be perfuse through artery for treating
specific areas.
Intra-arterial injection:
22. • Drug is injected into the subarachnoid space. Needles are inserted
through the vertebral interspinous spaces into the spinal fluid, by
lumbar puncture
• This route is used to produce intense action of drugs on
cerebrospinal system while treating infectious types of meningitis
or to produce spinal anaesthesia or for introduction of radio-
opaque contrast media into the subarachnoid spaces to visualize
the spinal cord (myelography)
Intra-thecal (Intra-spinal) injection:
23. • By this method the drug is deposited through the
vertebral interspaces between the dura of the spinal
cord and the periosteal linning of the spinal canal
• It is used to produce epidural nerve block by
depositing the local anaesthetic solution in the space
where spinal nerves emerges from the dural membrane
and enter the intervertebral formina .
Epidural injection:
24. • In some emergency conditions like sudden cardiac
arrest during anesthesia, electrocution ,injection of
adrenaline given directly into the heart may restart the
heart beat. The injection is given by a long needle in the
left fourth intercostal space close to the sternum.
Intracardiac injection :
25. • The drug is injected into the joint spaces to attain
the high local concentration within inflamed joint,
without much danger of systemic steroid toxicity
Intra-articular injection:
