Controlled Drug Delivery System ( CDDS)

INTRODUCTION                                                              

Drugs are administered through various Route such as oral, topical, parenteral, etc. Among all these routes, the oral route is the most common, convenient and popular. There are various reasons for such popularity. The most important and common reasons for their popularity are the convenience of administration, easy to carry and the ease of preparation of an industrial scale. About 80% of the dosage forms sold in the market are tablet dosage form. These dosage forms have been used since long, but these are found to have the following limitations.

1. The frequency of administration in a dry," is high.

2. It is difficult to monitor the daily dose, in many cases. It is not exactly maintained.

3. There is a greater chance of missing dose.

4. Non specific administration.

5.The careful calculation is required to prevent overdosing; it is difficult to calculate the exact dose for a child or elderly patient who should not receive the adult dose.

6. Hi concentrations can be toxic, closing side effects on damage to organs.

7. Consumption of more drug than necessity.

 

TERMINOLOGY

1. Delayed Release: Delayed release is a new concept of (NDDS), in this system the drug concentrate is divide into small packets polymer and they are coated to special polymer and after the going to the body into small small packets release and absorbed, they shows their action, that why the duration of action is increase.

2. Sustained Release: In the laboratory we make a drug, which specially modified with polymer coating and their disintegration time is increase they release is very slow manner and duration of action is long time. 

3. Site Specific Targeting: This technology is used for a particular site and particular organ for examples:- cancer, TB, diabetic etc.

4. Fast dissolving drug delivery system: These drug are highly dissolving tablet and their in disintegration time is less. They are chewable and after enter the Saliva of mouth drug start absorption from the mouth.

5. Controlled Release: it include the drug delivery system from which the drug is delivered at a predetermined rate and for predetermined period of time.

6. Extended Release: when absorption of drug is greater than its elimination it is known as extended release. Doses form should allow at at least two Fold reduction is doses frequency as compared to immediate release dosage form.

7. Receptor Targeting: in such system the target is particular receptor with in an organ of tissue.

Advantage of CDDs 

1. Prevention of side effects.

2. Reduction in healthcare cost.

3. Improve efficiency in treatment.

4. Eliminate overdosing or under dosing.

Disadvantages Of CDDs 

1. Dumping is measure disadvantages of CDDTs 

2. Poor in viva and invitro co-relation.

3. Difficult to optimise accurate dose and dosing interval.