This document discusses various dosage forms and routes of drug administration. It defines dosage forms as how drug molecules are delivered to the site of action in the body. Various dosage forms like tablets, capsules, solutions, and ointments are described. Different routes of administration like oral, sublingual, rectal, parenteral, intravenous, intramuscular, and topical are also explained. Factors influencing the selection of a particular route include the drug's properties, the rate of absorption needed, bypassing liver metabolism, targeting specific sites, dosage accuracy, and patient condition.

1. DOSAGE FORMS AND
ROUTES OF DRUG
ADMINISTRATION
Presented by Dr. Muhammad Usama

2. Dosage form of drugs
 Definition:
Means by which drug molecules/APIs
are delivered to the site of action within the
body to produce optimum desired effects and
minimum adverse effects.

3. Need of dosage forms
Why we need dosage forms?
1.Drug safety
2.Patient safety

4. Need of dosage forms(cont.)
 Provide:
1. Safe and convenient delivery of
accurate dosage.
Example: Tablets, syrups
2. Protection of drug substances from
atmospheric oxygen/moisture as well as from
gastric acid after oral administration.
Example: Capsules, sealed ampules, enteric
coated tablets

5. Need of dosage forms(cont.)
 Provide:
3. Liquid preparation of drug that is
insoluble/unstable in the desired vehicle.
Example: Suspension
4. Liquid dosage forms of substances soluble in
desired vehicle.
Example: Solution
5. Optional drug action from topical administration
sites.
Example: Ointment, cream, ear and nasal preparations
6. Optimal drug action through inhalational therapy
Example: Inhalants

6. Need of dosage forms(cont.)
 Provide:
7. Extended drug action through controlled
release mechanisms.
Example: Controlled release tablets, capsules
8. Insertion of drug into one of the body
orifices.
Example: Rectal and vaginal suppositories
9. Placement of drugs within body tissues.
Example: Implants
 Conceal bitter taste or odor of a drug substance.
Example: Capsules, coated tablets, flavored syrups

12. First-pass Effect
The first-pass effect is the term used for the
hepatic metabolism of a pharmacological
agent when it is absorbed from the 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

14. ORAL ROUTE
 It is the most common and acceptable route
for drug administration. Dosage forms are
tablet, capsule, syrup, mixture, etc., e.g.,
paracetamol tablet for fever, omeprazole
capsule for peptic ulcer are given orally.

15. ORAL
 Advantages:
1. Convenient for repeated and prolonged use,
can be self- administered, pain free
2. Absorption - takes place along the whole
length of the GI tract
3. Cheap - compared to other parenteral routes

16. ORAL
 It is not suitable for/in:
1. for emergency as onset of action of orally
administered drugs is slow
2. Unpalatable and highly irritant drugs
3. Unabsorbable drugs (e.g. aminoglycosides)
4. Drugs that are destroyed by digestive juices (e.g.
insulin)
5. Drugs with extensive first-pass metabolism (e.g.
lignocaine)
6. Unconscious patients
7. Uncooperative and unreliable patients
8. Patients with severe vomiting and diarrhea

17. SUBLINGUAL ROUTE
 Sublingual administration is where the dosage
form is placed under the tongue and is rapidly
absorbed by sublingual mucosa e.g.
nitroglycerin for acute anginal attack

18. SUBLINGUAL ROUTE
 ADVANTAGES
1. Economical
2. Action can be terminated by spitting out
3. First-pass avoided
4. Drug absorption is quick
 DISADVANTAGES
1. Unpalatable/Bitter drugs
2. Irritation of oral mucosa
3. Large quantities not given
4. Few drugs are absorbed

19. RECTAL ROUTE
 Drugs can be given in the form of solid or
liquid.
a. Suppository: solid dosage form used for local
effect as well as systemic effect. eg. diazepam
b. Enema: injection of fluid into lower bowel.
used more frequently to relieve constipation.

20. RECTAL ROUTE
 ADVANTAGES
1. USED IN CHILDREN
2. LITTLE OR NO FIRST PASS EFFECT
3. USED IN VOMITING/UNCONSCIOUS
4. HIGHER CONCENTRATIONS RAPIDLY
ACHIEVE

21. RECTAL ROUTE
 DISADVANTAGES
1. INCONVENIENT
2. ABSORPTION IS SLOW AND ERRATIC
3. IRRITATION OR INFLAMMATION OF
RECTAL MUCOSA CAN OCCUR

22. PARENTERAL
 Parenteral administration is injection or
infusion by means of a needle or catheter
inserted into the body
 This route of administration bypasses the
alimentary canal

23. PARENTERAL
 INJECTABLES
1. INTRAVENOUS
2. INTRAMUSCULAR
3. SUBCUTANEOUS
4. INTRA-ARTERIAL
5. INTRA-ARTICULAR
6. INTRATHECAL
7. INTRADERMAL

24. INTRAVENOUS
 Advantages:
1. Bioavailability is 100%.
2. Quick onset of action; therefore, it is the route of
choice in emergency.
3. Large volume of fluid can be administered, e.g.
intravenous fluids in patients with severe
dehydration.
4. Highly irritant drugs, e.g. anticancer drugs can
be given because they get diluted in blood.
5. Hypertonic solution can be infused by
intravenous route, e.g. 20% mannitol in cerebral
edema.

25. INTRAVENOUS
 Disadvantages
1. Local irritation may cause phlebitis.
2. Self-medication is not possible.
3. Once the drug is injected, its action cannot
be halted.
4. Strict aseptic conditions are needed.

26. INTRAMUSULAR ROUTE
 Advantages
1. Absorption is more rapid as compared to oral
route.
2. Mild irritants, depot injections, soluble
substances and suspensions can be given by
this route.

27. INTRAMUSULAR ROUTE
 Disadvantages
1. Aseptic conditions are needed.
2. Intramuscular injections are painful and may
cause abscess.
3. Self-administration is not possible.
4. There may be injury to the nerves.

28. SUBCUTANEOUS
 The drug is injected into the subcutaneous
tissues of the thigh, abdomen and arm. e.g.
adrenaline, insulin, etc.

29. SUBCUTANEOUS
 Advantages
1. Self-administration is possible (e.g. insulin).
2. Depot preparations can be inserted into the
subcutaneous tissue, e.g. Norplant for
contraception.
 Disadvantages
1. It is suitable only for nonirritant drugs.
2. Drug absorption is slow; hence it is not
suitable for emergency.

30. INTRA-ARTERIAL
 Rarely used
 Anticancer drugs are given for localized
effects
 Drugs used for diagnosis of peripheral
vascular diseases

31. INTRA-ARTICULAR
 Injections of antibiotics and corticosteroids are
administered in inflamed joined cavities by
experts.
Example: hydrocortisone in rheumatoid
arthritis

32. INTRADERMAL
 drug is given within skin layers (dermis)
 Painful
 Mainly used for testing sensitivity to drugs.
e.g. penicillin, ATS (anti tetanus serum)
 INOCULATION :administration of vaccine
(like small pox vaccine )

33. Topical Route
 Topical administration is the application of a drug
directly to the surface of the skin
 Includes administration of drugs to any mucous
membrane
 Eye
 Nose
 Ears
 Lungs
 Vagina
 Urethra

34. Topical Dosage Forms
 Dose forms for topical administration include:
1. Skin:
 creams
 ointments
 Lotions
 gels
 transdermal patches
2. Eye or ear:
 – solutions
 – suspensions
 – ointments
3. Nose:
 – sprays and powders

35. SELECTION OF ROUTE
 The ROA is determined by :
 the physical characteristics of the drug
 the speed by which the drug is absorbed and
released
 the need to bypass hepatic metabolism
 to achieve high conc. at particular sites
 Accuracy of dosage
 Condition of the patient

38. THANK YOU 