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Flashcards in Drug delivery system Deck (35):
1

3 factors affecting dosage regime/delivery sys we use

drug dose
frequency and timing of administration

2

Oral Medication are commonly used and absorption is via ...

GI tract

3

Absorption is via the GI tract for these routes of administration

Buccal Sublingual
Oral
Rectal

4

Solutions and Suspensions: Absorption depends on ........ and is most rapid from the .......

1. Gastric emptying
2. small intestine

5

Dispersions of coarse drug particles in a liquid phase

suspensions


dose can be containe din small vol
good for drugs which are insoluble unpalatable - better tolerated

6

Hydrogel polymer release sys given in high dose are intact slowly releasing the effect.

Modified controlled release tablets

7

most commonly used formulation

tabs and capsules

8

...... or tablet break down is the ......... in absorption

1. Dissolution
2. rate limiting step

9

......... delays disintegration of the tablet until it reaches the small intestine

Enteric coating

10

Tablets are enteric coated to:

Protect the drug from stomach acid (Omeprazole)

Protect the stomach from the drug (Aspirin)

11

Maintains drug level within therapeutic range and reduce the need for frequent dosing
rate of abs reduced
high dose but released slowly over a period of time
Always use the SAME brand name for this!!!!!

Prolonged or delayed release formulations

12

Oral Preparations ◦Verapamil◦Diltiazem◦Isosorbide mononitrate◦Lithium◦CarbamazepineProblems with possible toxicity`Parenteral Preparations◦Intramuscular injections of flupenthixol or risperidone`Surgical Implants◦Progesterone contraception◦Testosterone

.Prolonged or delayed release formulations

13

synthesised inactive derivatives of an active drug which requires to be metabolically activated after administration

Prodrug

The advantages of using prodrugs are◦prolongation of duration of action◦avoidance of degradation of the drug in the gut

14

For drugs which have extensive pre-systemic or first pass metabolism
- small and dissolve slowly upon administration

Buccal and sublingual administration
Most common example is GTN

15

Drugs may be administered ......
◦to treat.......conditions such as proctitis ◦to achieve ...... absorption (indomethacin)
Bypass pre-systemic metabolism

rectally
local
systemic



Administered as a suppository

16

.... administration when a drug has a short half-life, quick action and careful control of [plasma] required

IV

17

Drug - insoluble or oil formulation.Allows a more sustained duration of action up to months .Depot Injections contraceptive, neuroleptics

Intramuscular injection

18

A common route of administration

Easy to use and bypasses need for venous access

Used for insulin, heparin and narcotic analgesics

Subcutaneous Injection

19

Transdermal drug delivery sys

Percutaneous

20

Creams, ointments and skin patches

percutaneous
(transdermal)

drugs admin to skin - local effect (steroids) or systemic effect (HRT or nitroglycerin)

21

Release of a drug from a reservoir into the skin and then into the systemic circulation

controlled, sustained blood levels of the administered drug such as nicotine, nitroglycerin, opiates, HRT, contraception

Skin patches

22

Deliver drugs directly to the lung for local effect or to achieve a systemic effect I.e anaesthetics

Inhalation

Advantages◦Drug delivered directly to site of action◦Rapid effect◦Small doses used◦Little systemic absorption◦Reduced adverse effects`Disadvantages◦Patient education is essentia

23

It is a sub-cutaneous needleless injection used for mass inoculation

Dermojet (insulin injector/pin-prick blood check)

24

Drug as a solid pellet is implanted under the skin to provide uniform systemic effect .Eg:testosterone

Pellet implantation

25

Used for motion sickness

Transderm-SCOP (Scoplamine)

26

Hydrogel transdermal patch:

Used in treatment of burns

27

Pharmaceutical carriers (Carrier based drug delivery sys)

Micelles
Liquid crystals
nanocapsules
nanopheres
vesicles
multifunctional dendritic polymers

28

mAbs act directly when binding to a cancer specific antigen and induce immunological response to cancer cells
mAbs have been modified for delivery of a toxin, cytokine or other active drug

Monoclonal antibodies

29

Pre-clinical and clinical liposomal packed drugs exhibit reduced toxicities with enhanced efficiency
Due to altered pharmacokinetics-drug accumulation at disease sites and reduced distribution to sensitive tissue-target delivery of drugs

Liposomal Drug delivery

Liposomes are self-assembling closed colloidal structures composed of lipid bilayers and have a spherical shape in which an outer lipid bilayer surrounds a central aqueous space. Synthesised from cholesterol

30

Using nanotechnology the drug can be targeted to a precise location which would make the drug much more effective & reduce the chances of possible side-effects
More specific drug targeting & delivery
Reduction in toxicity while maintaining therapeutic efficiency
Nanocarriers- Nanoparticles,Nanotubule,Nanoshell

Nanoparticle based drug delivery

31

Used in treatment of Bronchial asthma
ADR: Foreign body granuloma and intestitial fibrosis

Carbon Nanotubules

32

Cancer chemotherapy
-free radical generation

Gold Nanoparticles

33

Nanoerythrosomes are resealed erythrocytes that can carry
proteins ,enzymes & macromolecules.
They are used in the treatment of liver tumour, parasitic disease
& enzyme disease

Nanoerythrosomes

34

-highly branched globular
Biodegradable synthetic molecule

Dendrimer

35

They deliver radioactivity to tumour.Eg:C-60 against CA colon
Transfer of radiation is within the ball hence minimise strong radiation to healthy tissue.

Modified Buckyball