What is sustained drug release?
Sustained release allows delivery of a specific drug at a programmed rate that leads to drug delivery for a prolonged period of time (Moghimi et al., 2001). This approach of drug release is especially useful for drugs that are metabolized too fast and are eliminated from the body shortly after administration.
Which implants do not contain any moving parts?
Passive Polymeric Implants. These are normally relatively simple devices with no moving parts, they rely on passive diffusion for drug release. They are generally made of drugs packed within a biocompatible polymer molecule.
What is matrix tablet?
A matrix tablet is formed when an active drug is homogeneously dispersed (embedded) in an inert material. Matrix materials are often swellable hydrophilic or non-swellable hydrophobic polymers. The material properties affect the rate of drug release through factors including diffusion, permeation, and dissolution.
What is meant by sustained or slow release?
Definition of sustained-release : designed to release a drug in the body slowly over an extended period of time.
How do matrix tablets work?
The primary mechanism of drug release from hydrophilic matrices occurs when the polymer swells on contact with the aqueous medium to form a gel layer on the surface of the system. The drug then releases by dissolution, diffusion and/or erosion (Colombo 1993, Ishikawa et al.
What is a hydrophilic matrix system?
Commonly, hydrophilic matrices are compressed matrix tablets and can easily be prepared by direct compression of a powder mixture of drug with a release retardant, swellable polymer and other additives to aid processing.
What is biodegradable implant?
Biodegradable implants are derived by transforming compounds that are present in nature to structural plastics. Organic molecules are polymerized to form strong fibers and solid compounds. When these polymers are implanted in patients, they degrade and are eliminated from the body in a period of time.
What is sustained release drug delivery?
Sustained release allows delivery of a specific drug at a programmed rate that leads to drug delivery for a prolonged period of time (Moghimi et al., 2001). This approach of drug release is especially useful for drugs that are metabolized too fast and are eliminated from the body shortly after administration.
What is a drug delivery system?
A drug delivery system (DDS) is defined as a formulation or a device that enables the introduction of a therapeutic substance in the body and improves its efficacy and safety by controlling the rate, time, and place of release of drugs in the body.
What are the advantages of sustained release tablets?
The advantages of sustained release tablets or capsules are that they can often be taken less frequently than instant formulations of the same drug and that they keep steadier levels of the drug in the bloodstream. By several approaches the residences time of drug delivery system in the gastrointestinal tract can be prolonged.
How to manufacture sustained release dosage forms?
One of the least complicated approaches to the manufacture of sustained release dosage forms involves the direct compression of blends of drug, retardant materials and additives to form a tablet in which drug is embedded in matrix core of the retardant. Alternately, retardant drug blends may be granulated prior to compression.