This document discusses the various routes of drug administration. There are three main routes: enteral, parenteral, and topical. The enteral route involves absorption through the gastrointestinal tract using oral, sublingual, buccal, or rectal administration. The parenteral route bypasses the gastrointestinal tract through injections like intravenous, intramuscular, or subcutaneous. The topical route applies medications directly to the skin or mucous membranes of the eyes, nose, ears, vagina or urethra using forms like creams, ointments, or patches. The selected route depends on the drug properties and the needs of the patient.

1. Routes of Drug Administration
Prepared by: Ms. Iqra shafique

2. Channels of drug administration
Following are the routes of medicine
administration:
1. Enteral
2. Parenteral
3. Topical

3. Enteral route
• The enteral routes of administration are those
in which the drug is absorbed from the
gastrointestinal tract. These include
• Oral
• Sublingual
• Buccal
• Rectal Routes

4. Oral
• Oral route refers two methods of administration
Applying topically to the mouth
Swallowing for absorption
along gastrointestinal (GI) Tract into systemic
circulation.

5. Common dose forms for oral medicine
• Tablets
• Capsules
• Liquids
• Solutions
• Suspensions
• Syrups
• Elixirs

6. First- pass effect
• The first pass effect is the term used for the
hepatic metabolism of a pharmacological
agent when it is absorbed from gut and
delivered to the liver via the portal circulation.
• The greater the first-pass effect, the less the
agent will reach the systemic circulation when
the agent is administered orally.

7. Sublingual route
• Sublingual administration is where the dosage
form is placed under the tongue.
Rapidly absorbed by sublingual mucosa.

8. Buccal route
• Buccal administration is where the dosage
form is placed between gums and inner lining
of the cheeks( buccal pouch).
• Absorbed by buccal mucosa.

9. Rectal route
• Rectal administration uses the rectum as a
route of administration for medication and
other fluids, which are absorbed by the
rectum's blood vessels, and flow into the
body's circulatory system, which distributes
the drug to the body's organs and bodily
system.

10. Cont.
• These rectal formulations are based on
conventional dosage forms, such
as suppositories and enemas, and are
typically used for short-term therapy

11. Systemic – Parenteral
• Parenteral administration is injection and
infusion by means of a needle or catheter
inserted into the body.
• The term parenteral comes from Greek words
- Para meaning outside
- Enteron, meaning the intestine
• This route of administration bypass the
alimentary canal.

12. Injectable includes in parenteral
• Intravenous
• Intramuscular
• Subcutaneous
• Intradermal
• Intra-arterial (Within an artery)
• Intra-articular (directly into the joint)
• Intrathecal (directly into the spinal cord)
• Inhalation (absorption through lungs)

13. Intra –arterial
• Rarely used.
• Anticancer drugs are given for localized effects
• Drugs used for diagnosis of peripheral vascular
diseases.

14. Intra – articular
• Injections of antibiotics and corticosteroids
are administered in inflamed joint cavities by
experts.
• Hydrocortisone in
rheumatoid arthritis.

15. Intrathecal
• The fluid-filled space between the thin layers
of tissue that cover the brain and spinal cord.
• Drugs can be injected into
the fluid or a sample of the
fluid can be removed
for testing.

16. Intradermal
• Drugs is given within the skin layers.
• Painful
• Mainly used for testing sensitivity to drugs.
e.g. penicillin, ATS(anti tetanus serum)
Inoculation : administration of vaccine (like
small pox vaccine).

17. Topical routes of administration
• The application of drug directly to the surface
of the skin.
• Includes administration of drugs to any
mucous membrane
Eye
Nose
Ears
Vagina
Urethra

18. Topical dosage forms
Dose forms for topical administration includes:
• Skin
Creams
Ointments
Lotions
Gels
Transdermal patches
Disks

19. Cont.
• Eye or ear
Solutions
Suspensions
Ointments
• Nose
Sprays

20. Selection of route
• The ROA is determined by:
The physical characteristics of the drugs.
The speed which the drug is absorbed and
released.
The need to bypass hepatic metabolism.
To achieve high concentration at particular
sites.
Accuracy of dosage.
Condition of the patient.