This document discusses pulsatile drug delivery systems (PDDS), which aim to release drugs in a programmed pattern that corresponds to circadian rhythms or specific disease states. It outlines the objectives and methodology. Key points include: PDDS are advantageous over sustained release for diseases with circadian rhythms; examples are hypercholesterolemia, asthma, diabetes, and cardiovascular diseases. The document classifies and describes different types of PDDS, including internal stimuli-induced, temperature-induced, pH-sensitive, glucose-responsive, time-controlled, inflammation-induced, and externally regulated systems. In conclusion, PDDS can effectively deliver drugs according to the body's circadian clock.

1. PULSATILE DRUG DELIVERY
SYSTEM
(PDDS)
Prepared by: Manoj Paudel
III Semester
Roll No: 124
Department Of Pharmacy

2. Objectives
 Introduction of PDDS
 Necessities of PDDS
 Types of PDDS

3. METHODOLOGY
 Review journals
 Assistance from faculty teacher

4. PULSATILE DRUG DELIVERY
SYSTEM(PDDS)
 It is defined as the rapid and transient release of a
certain amount of drug molecules within a short time-
period immediately after a predetermined off-release
period i.e. lag time
 It aims to release drug on programmed pattern
 PDDS are advantageous over sustained release drugs
because many of diseased condition follow some
circadian rhythm
 For which maintaining the drug plasma level is not a

6. Disease Demanding The
PDDS
 Hypercholesterolemia
 circadian rhythm occurs during hepatic
cholesterol synthesis
 cholesterol synthesis is generally higher during
the night than during daylight
 maximal production occurs early in the morning,
i.e. 12 h after the last meal
 Studies suggests evening dosing to be effective
than morning

7.  Asthma
 airway resistance increases progressively at night in
asthmatic patients
Duodenal ulcer
 gastric acid secretion is highest at night , while
gastric and small bowel motility and gastric emptying
are all slower at night
 peptic ulcer patients, gastric acid secretion is highest
during the night
Thus bedtime dosage is much effective

8.  Diabetes
 Insulin level varies with time
 It is highest after meal
 Thus PDDS is of demand which release the in
response to the plasma insulin concentration
Cardiovascular diseases
 Blood pressure (BP), heart rate, stroke volume,
cardiac output, blood flow of the cardiovascular
system are subject to circadian rhythms
 BP is at its lowest during the sleeping period and
rises steeply during the early morning period

9.  capillary resistance and vascular reactivity are
higher in the morning and decrease later in the
day
 Thus Demands a PDDS

12. NECESSITIES OF PDDS
 First pass metabolism
 Biological tolerance
 Special chronopharmacological needs
 Local therapeutic need
 Gastric irritation or drug instability in GI tract

13. Classification of PDDS
PDDS
Internal stimuli
induced
system
Temperature
induced
PH sensitive
Inflammation
induced
Glucose
responsive
Time
Controlled
Externally
regulated

14. Internal Stimuli Induced
System
 drug release takes place after stimulation by
any biological factor like temperature, or any
other chemical stimuli
 Chemical Stimuli
1. Enzymes
2. Hormones
3. pH

15. Temperature Induced Drug
Release
 Deviation of temperature acts as stimulus and
triggers drug release
 Useful for disease accompanying fever

16. pH Sensitive Drug Release
 polyelectrolytes that bear weak acidic or basic
groups that either accept or release protons in
response to changes in environmental pH are
used for drug release
 Polyeectrolytes are cellulose acetate
phthalate, polyacrylates, sodium carboxy
methyl cellulose.

17. Glucose Responsive
 Increased concentration of either Glucose
oxidase or Gluconic acid lowers the pH to
approx 5.8
 pHsensitive hydrogels for modulated insulin
delivery
GLUCOS
E
Gluconic
acid
Glucos
e
Oxidas
e

18.  pHsensitive hydrogels for modulated insulin
delivery
 pH change induces swelling of the polymer which
results in insulin release.
 Insulin reduces blood glucose level
 gluconic acid level also gets decreased and
system turns to the deswelling mode thereby
decreasing the insulin release.

19. Inflammation Induced
 Physical or chemical stress, such as injury,
broken bones, etc., initiates inflammation
reactions, because of which hydroxylradicals
('OH) are produced from these inflammation-
responsive cells.
 Hyalauric acid(HA) was used for the
inflammation induced delivery system.

20.  HA is mainly degraded either by hydroxyl
radicals or a specific enzyme, hyaluronidase
 Degradation by Hydroxyl radical is more
prominent
 Thus, it is possible to treat patients with
inflammatory diseases like rheumatoid
arthritis; using anti-inflammatory drug
incorporated in HA gels as new implantable
drug delivery systems

21. Time Controlled
Rupture Of Coating
 these systems are dependent on the
disintegration of the coating for the release of
drug
 Pressure for the rupture of the coating is achieved
by the swelling, disintegrants or osmotic pressure
Erosion or Solubilization of Layer
 the core containing drug is coated with the soluble
or erodible polymer as outer coat and drug
release is controlled by the dissolution or erosion
of the outer coat

23. CAPSULAR SYSTEM FOR PULSATILE
RELEASE

24. Externally Regulated
 Magnetic induces release
 Ultrasound induces release
 Electric field induces release
 Light induces release

25. Conclusion
 PDDS is useful in disease following biological
rhythm
 In Circadian disorders such as hypertension,
osteoarthritis, asthma etc., which require
chronopharmacotherapy
 PDDS can effectively tackle this problem as it
is modulated according to body's circadian
clock giving release of drug after a specified
time lag
 Various pulsatile technologies are researched
and some are currently in the market.

26. References
1. http://media.wix.com/ugd/5ccba3_0b3e45df793cb580b
1302d85830accb7.pdf
2. http://www.ijpbs.net/vol-2_issue-
3/pharma_science/39.pdf