concepts of novel drug delivery

1. BASIC CONCEPTS OF
CONTROLLED AND
NOVEL DRUG DELIVERY
SYSTEM
PRESENTED BY,
DR. ANITA DESAI
HOD AND PROFESSOR
DEPT. OF PHARMACEUTICS
HSK COP BAGALKOT

2. CONTENTS:
1. Definitions
2. Parenteral
3. Transdermal
4. Buccal
5. Rectal
6. Nasal
7. Implants
8. Occular

3. DEFINITIONS:
• CONTROLLED RELEASE DOSAGE FORMS :
Dosage form which release drug at a constant rate and
provide plasma concentration that remains invariant with
time.
• “Novel Drug delivery System (NDDS) refers to the
formulations, systems and technologies for transporting
a pharmaceutical compound in the body as it is needed
to safely achieve its desired therapeutic effects.

4. PARENTERAL CONTROLLED DRUG
DELIVERY SYSTEM:
Definitions:
Parenteral controlled drug delivery system is the novel
approach where drug is delivered at predetermined rate at
particular site after administered through pricking into
body i.e., through parenteral routes.

5. Concept :
• As we know that the intra venous, subcutaneous, intra
muscular, intra peritoneal and intra thecal routes are all
examples of parenteral routes of drug administration.
• In controlled release parenteral dosage forms the
concentrated routes are the subcutaneous & intramuscular
routes.
• Drug molecules will be released continuously from the
reservoir at a rate determined by the characteristics of
each formulation.
• This continuous release of drug molecules will result in a
prolonged drug blood level.
• The rate of absorption and hence duration of therapeutic
activities will be determined by the nature of the vehicle.

6. Advantages :
1. Improved patient convenient and compliances.
2. Fluctuations in steady state levels are less.
3. Increased safety margin of high potency drugs.
4. Maximum utilization of drugs.
5. Reduction in health care costs through improved therapy,
less cost treatment and reduced frequency of dosing.

7. Disadvantages:
1. Decreased systemic availability.
2. Poor in vitro- in vivo correlation.
3. Possibility of dose dumping.
4. Withdrawal of drug is difficult in case of toxicity,
poisonings or hypersensitivity reactions.
5. Reduced potential for dose adjustments.
6. High cost of formulations.

8. Types of Parenteral Controlled Drug Delivery System
1. Inject able drug delivery
2. Implantable drug delivery system i.e., they are may be of
depot type.

9. Examples of few Injectable controlled release formulations
1. Long-acting Penicillin Preparations
2. Long-acting Vitamin B12 preparations
3. Long-acting Adreno corticotropic Hormone Preparations
4. Long-acting Steroid preparations
5. Long-acting Antipsychotic Preparations
6. Long-acting Antinarcotics Preparations
7. Long-acting Contraceptive Preparations
8. 8. Long-acting Insulin Preparations

10. TRANSDERMAL DRUG DELIVERY
SYSTEM
Definitions :
Transdermal Drug Delivery System (TDDS) are defined as
self contained, discrete dosage forms which are also
known as “patches” when patches are applied to the
intact skin, deliver the drug through the skin at a
controlled rate to the systemic circulation.

11. CONCEPT:
Basic Principal of Transdermal permeation:
• Transdermal permeation is based on passive diffusion.
• Skin is the most intensive and readily accessible organ of
the body as only a fraction of millimeter of tissue
separates its surface from the underlying capillary
network.
• The release of a therapeutic agent from a formulation
applied to the skin surface and its transport to the
systemic circulation is a multistep process, which includes

12. 1) Diffusion of drug from drug to the rate controlling
membrane.
2) Dissolution within and release from the formulation.
3) Sorption by stratum corneum and penetration through
viable epidermis.
4) Uptake of drug by capillary network in the dermal
papillary layer.
5) Effect on the target organ.
6) Partitioning into the skin’s outermost layer, the stratum
corneum.
7) Diffusion through the stratum corneum, principal via a
lipidic intercellular pathway

13. Advantages:
 Avoidance of first-pass effect,
 Long duration of action,
 Ease of termination of drug action, if necessary,
 No interference with gastric and intestinalfluids,
 Suitable for administered of drug having- Very
short half-life, e.g. nitroglycerine.

14. Disadvantages:
 Poor diffusion of largemolecules,
 Skin irritation,
 Unsuitable –If drug dose is large,
 Absorption efficiency is vary with different sites of skin,
14

15. CLASSIFICATION OF TDDS
 A. Rate-Programmed
Systems
1. Drug in Reservoir
2. Drug in Matrix
3. Drug inAdhesive
4. Drug in Micro reservoir
 B. Physical Stimuli-
Activated Systems
1. Structure-Based Systems
2. Electrically-Based Systems
 Iontophoresis
 Electroporation
 Sonophoresis

16. BASIC COMPONENTS OF TDDS
 Polymer matrix / Drug reservoir
 Drug
 Permeation enhancers
 Pressure sensitive adhesive(PSA)
 Backing laminate
 Liner

17. Examples :
1. Transdermal Scopolamine
2. Transdermal Nitroglycerine

18. BUCCAL DRUG DELIVERY SYSTEMS
DEFINITION:
Buccal delivery is defined as the drug administered
through the mucosal membranes lining the cheeks
(Buccal mucosa).

19. PRINCIPLE OF MUCO-ADHESION:
In this system Muco-adhesive polymers acts as drug
delivery vehicle. The common principle underlying this
drug administration route is adhesion of the dosage form to
the mucus layer until the polymers dissolves or the mucin
replaces itself.
The term Bio-adhesion implies the attachment of drug
carrier system to specific biological location. This biological
surface can be epithelial tissue or the mucus coat on the
surface of tissue. If the adhesive attachment is to mucus coat
then the phenomenon is referred as Muco-adhesion.

20. Advantages of BDDS:-
 Drugs which are unstable in acidic environment of
stomach or which are destroyed by alkaline environment
of intestine can be given by this route.
 Drugs which undergo enzymatic degradation can also be
given by this route.
 Termination is possible in case of emergency.
 Drugs with short half-life (2-8hrs) can be administered.
 It provides improved patient compliance due to
elimination of pain with injection.
 It can be easily administered to unconscious and less
cooperative patients.
 The major advantage of buccal drug delivery is that it
bypasses hepatic first pass metabolism.

21. Disadvantages of BDDS:-
 Drugs which irritate the mucosa or have a bitter or
unpleasant taste or odor cannot be given.
Eg. Methotrexate
 Drugs unstable at buccal pH cannot be given.
 Eating and drinking may become restricted.
 Only those drugs which follow passive diffusion may be
given.
 Only those drugs with small dose requirement may be
given.
 If formulation contain antimicrobial agent then it will
affect natural microbes in buccal cavity.

22. Various approaches are:
1. Buccal tablet
2. Buccal patches/films
3. Buccal ointment/gel
Examples:
1. Nitroglycerine bio-adhesive tablet for the treatment of
angina pectoris.
2. Buccal film of salbutamol sulphate and terbutalin
sulphate for the treatment of asthma.
3. Buccal adhesive film of clindamycin used for pyorrhea
treatment.
4. Xylonor gel used for topical anaesthesia in buccal cavity.

23. RECTAL DRUG DELIVERY SYSTEMS
Definitions:
Rectal drug delivery system is a type of mucoadhesive drug
delivery systems. Such systems involves mucoadhesion ,
i.e. the attachment of the drug along with a suitable carrier
to the mucous membrane.

24. Concept:
• The rectal route though rarely the first choice of drug
administration, serves as an alternative to oral and
invasive administration.
• Rectal drug delivery is so pivotal when the oral
medication is not possible, intra venous access is not
possible and when the patients have difficulty in
swallowing, nausea and vomiting.
• For a long period of time the rectal route was used only
for the administration of local anesthetics,
antihemorrhoidal, vermifugal, anti-bacterial and laxative.

25. Advantages
1. Irritation to the stomach and small intestine associated
with certain drugs can be avoided. E.g.- NSAIDs: Aspirin,
Ibuprofen, Naproxen.
2. Absorption enhancement of many low molecular weight
drugs, proteins and peptides.
3. Contact with digestive fluid is avoided, thereby
preventing acidic and enzymatic degradation of some
drug. E.g. - Protein peptide drug delivery by rectal offers
low levels of protease activity particularly of pancreatic
origin.
4. Hepatic first pass elimination of high clearance drug may
be partially avoided. E.g. - Lidocaine, Proponalol,
Morphine, etc.

26. Disadvantages
1. Many drugs are poorly or erratically absorbed across the
rectal mucosa.
2. Dissolution problems due to the small fluid content of the
rectum.
3. Drug metabolism by micro organisms and rectal mucosa.
4. They are inconvenient and not preferred by patients.
5. Frequently unpredictable because of leak or expulsion
after insertion.

27. Examples:
suppositories
Enemas
Aerosols
Ointments/gels

28. NASAL DRUG DELIVERY SYSTEMS
Definitions
Nasal drug delivery is the approaches where the drug is
administered through nasal routes to reach systemic
circulation for better bioavailability.

29. Advantages :
1. Improving patient compliance
2. Good penetration
3. rapid absorption and onset of action
4. Avoidance of the harsh environment
5. low dose required
6. Direct delivery of drug to central nervous system

30. Disadvantages:
• Risk of local side effect and irreversible damage of cilia
on nasal mucosa
• Disrupt and even dissolve the nasal membrane
• Reduce the capacity of nasal absorption
• Low bioavailability

32. IMPLANTABLE DRUG DELIVERY
SYSTEMS
Definitions
These are the approaches where the therapeutic drugs are
most effective when they are delivered into the
bloodstream steadily, Such delivery can be accomplished
by the surgical implantation of a drug pellet, a reservoir or
a pump.

33. ADVANTAGES :
1. Controlled drug delivery for a long time period.
2. Improved patient compliance.
3. Targeted drug delivery.
4. Bypasses first pass metabolism.
5. Decreased side effects.
6. Improved stability of drugs.
7. Improve bioavailability of drugs.

34. DISADVANTAGES
1. Surgery is needed for large implants (Painful).
2. Therapy cannot be simply discontinued.
3. Reactions between host & implant.
4. Inadequate release of API.

36. Examples:

37. OCCULAR DRUG DELIVERY
SYSTEMS
Definitions
Occular drug delivery system: These are the special dosage
forms designed to be instilled onto the external surface of
the eye (topical),administered inside(intraocular)or
adjacent(periocular) to the eye or used in conjuction with
the devices.

38. The following characteristics are required to optimize ocular
drug delivery systems .
• A good corneal penetration.
• A prolonged contact time of drug with corneal tissue.
• Simplicity of installation and removal for the patient.
• A non-irritative and at ease form (the viscous solution
should not irritate lachrymation and reflex flashing).
• Appropriate rheological properties and concentration of
viscolyzer.

39. Advantages:
• Good corneal penetration.
• Maximum ocular drug absorption through prolong contact
time with corneal tissue.
• Simplicity of instillation for the patient.
• Reduced frequency of administration.
• Lower toxicity and side effects.
• Minimum precorneal drug loss.

40. Disadvantages:
• Less stable
• Bioavailability is less
• In case any toxicity it is not able withdraw
• In convenient for patients
• Blurring of visions
• Skilled person is required to handel

41. Various approaches are:
Occuserts
Contact lenses
Iontophoresis
Liposomes form

43. REFERENCES
• NOVEL DRUG DELIVERY BY N.K.
JAIN
• Google images.com