Question

1. Compare and contrast between conventional drug delivery system and sustained drug delivery system according to: order release kinetics and drug localization mechanism.

2. What are the limitations and problems associated with using a sustained dosage form?

Answer 1

1. Compare and contrast between conventional drug delivery system and sustained drug delivery system according to: order release kinetics and drug localization mechanism.

Sl. No		Conventional Drug Delivery	Sustained Drug Delivery
1.	Definition	The conventional drug generally result in relatively rapid drug absorption and onset of accompanying pharmacodynamic effects, delivery system is the absorption of the drug across a biological membrane.	Sustained Release Drug Delivery System (SRDDS) is designed to release a drug at a predetermined rate by maintaining a constant drug level for a specific period of time with minimum side effects.
2.	Kinetics of the drug	The pharmacokinetics is divided into Absorption: - cellular levels, mouth, stomach, duodenum Metabolism: - inside the cells, short half life. Distribution: - receptors on the biological membrane Excretion: - through venous circulation	The pharmacokinetics is divided into Absorption: - duodenum, lower parts of jejunum and ileum. Metabolism: - liver, with specific half life Distribution: - circulatory system Excretion: - through GI & kidney
3.	Drug Localisation Mechanism	Drug is localised to the area of application and sometimes localised to the area of affect	These drugs are coated drugs or programmed slow release drugs which act on larger areas of localisation and dynamically are more dominant than other drugs

2. What are the limitations and problems associated with using a sustained dosage form?

1. Any over dosage is fatal

2. It does not permit prompt termination of therapy.

3. Less flexibility in dose adjustment.

4. These dosage forms are designed on the basis of average biological half-life, but in these they have long half life leading to larger discrepancies.

5. They are costly.