A review on polymers in natural or modified form used in sustained release tablet

Abstract

Tablet is a solid dosage form which is used to deliver the drug to the body to make pharmacological action. The oral dosage form should disperse into small particles to deliver active ingredients in the body, the disperse time of the dosage form depends on the ingredients which are used in the tablet. To make the tablet disintegrate slow usually sustained release agents are used. The sustained release tablets helps in maintaining the drug concentration in the body for the higher time. In this review article various polymers of natural origin and their modified forms are studied, which can be used in the sustained release tablet. In this review article the polymers studied were, Psyllium husk, HPMC K100M, Cellulose polymers, Cellulose ether polymers, Xanthan gum, Guar gum, Eudragit RLPO, Eudragit RSPO, Eudragit RL 100, Eudragit RS 100, Kollidone SR and Carnauba wax. Now a day the sustained release tablets are used more than the conventional tablets because of the patient incompliance. The main part of the sustained release tablets are the polymers. In the study it was found that the modified forms of natural polymers works better than in their natural form. In the study it was found that the hydrophilic polymers also work better like Xanthan gum and Guar gum, they are effecting and non-toxic in nature. The cellulose derivatives were studied and it was found that Substituted cellulose-methylcellulose, hydroxypropylcellulose and hydroxypropylmethylcellulose works better in the combination form.

Keywords: Sustained release, Xanthan gum, Guar gum, Eudragit, Kollidone, HPMC