What is Gastroretentive?
Gastroretentive drug delivery system is novel drug delivery systems which has an upper hand owing to its ability of prolonged retaining ability in the stomach and thereby increase gastric residence time of drugs and also improves bioavailability of drugs.
What are Gastroretentive drug delivery systems?
Gastroretentive drug delivery systems are a good example; they emerged to enhance the bioavailability and effectiveness of drugs with a narrow absorption window in the upper gastrointestinal tract and/or to promote local activity in the stomach and duodenum.
What may be the reason of development of Gastroretentive drug delivery system?
Gastroretentive drug delivery systems potentially prolong the gastric retention time and controlled/sustained release of a drug, thereby increasing the concentration of the drug at the application site, potentially improving its bioavailability and reducing the necessary dosage.
Which drug is not suitable for Grdds?
7 UNSUITABLE DRUGS FOR GRDDS 7 1] Drugs That Have Very Limited Acid Solubility E.g. Phenytoin, Etc. 2) Drugs That Suffer Instability In The Gastric Environment. E.g. Erythromycin, Etc. 3) Drugs Intended For Selective Release In The Colon E.g. 5-amino Salicylic Acid And Corticosteroids, Etc.
Which drug is suitable for Grdds?
6 SUITABLE DRUGS FOR GRDDS 6 • Drugs acting locally in the stomach. E.g. Antacids and drugs for H. Pylori , Misoprostol. Drugs that are primarily absorbed in the stomach.
Which substance is used as mucoadhesive?
Typical examples include poly (acrylic acid) (PAA) and its weakly cross-linked derivatives and sodium carboxymethylcellulose (NaCMC). PAA and NaCMC possess excellent mucoadhesive characteristics due to the formation of strong hydrogen bonding interactions with mucin.
What is the principle of Mucoadhesion?
Diffusion Theory of Mucoadhesion Diffusion theory describes that polymeric chains from the bioadhesive interpenetrate into glycoprotein mucin chains and reach a sufficient depth within the opposite matrix to allow formation of a semipermanent bond.
What are mucoadhesive agents?
Mucoadhesion describes the attractive forces between a biological material and mucus or mucous membrane. For example, in drug delivery systems, the mucus layer must be penetrated in order to effectively transport micro- or nanosized drug particles into the body.
Which is poor mucoadhesive polymer?
At lower concentrations of the polymer chains, there is an inadequate and unstable interaction amongst the poly- mer and the mucosal layer resulting in poor mucoadhesive properties. The contact time amongst the polymer matrix and the mucosal layer can also govern the mucoadhesive property.
Which is innovative technology for gastro-retentive drugs?
GRID is designed to offer longer retention times in the stomach, of about eight hours, for such drugs. This innovative system is a dosage form with specialized multiple coatings. On ingestion of the dosage form along with food, it floats instantaneously on the gastric contents.
Which is an example of a gastro retentive drug delivery system?
Gastro-retentive drug delivery system (GRDDS) is one such example where the attribute like gastric retention time coupled with the drug release for extended time has significantly improved patient compliance. Some inherent limitations of the conventional oral drug delivery systems have ignited the interest to this new delivery system.
How long does a gastroretentive drug stay in the stomach?
Gastroretentive dosage forms can remain in the gastric region for long periods and hence significantly prolong the gastric retention time (GRT) of drugs.
Why is recurrent dosing required for gastro retentive drugs?
To attain required therapeutic activity, recurrent dosing is needed for the drugs with short half-lives as they have the tendency of getting eliminated quickly from the systemic circulation.