<![CDATA[Sustained release tablets are dosage forms developed to maintain drug concentrations within the therapeutic range for a longer period, reduce dosing frequency, and improve patient compliance. Various formulation approaches have been employed to achieve controlled drug release, mainly through hydrophilic matrix, hydrophobic matrix, and floating systems. This article presents a narrative review of five studies congcerning susteined release tablet formulations containing synthetic drugs and herbal extracts, namely dipyridamole, metforminHCL, apirin, celery extract (Apium graveolens L.), and jatropha curcas L. Leaf extract. The studies were reviewed based on research objectives, formulation composition, polymer or matrix type, manufacturing method, evaluation parameters, and drug release performance. The riview shows that hydroxypropyl methylcellulose (HPMC), xanthan gum, chitosan, and ethyl cellulose are the most frequently used polymers to modify drug release. HPMC and xanthan gum generally provide hydrophilic matrix characteristics that support gel formulation and duffusion-erosion drug release, whereas ethyl cellulose acts as a hydrophobic matrix that retards dissolution medium penetration. In floating systems, the combination of HPMC with gas-generating agents or supporting polymers may prolong gastric residence time. Among the reviewed studies, the floating dipyridamole formula contining 30% HPMC K4M and 20% Ac-di-sol and the celery extract formula containing 52 mg xanthan gum and 3 mg megnesium stearate showed the most favorable sustained release performance. Overall, the success of sustained release tablet formulation is strongly influenced by matrix type, polymer proportion, active ingredient characteristics, and the targeted release mechanism. Keywords: Sustained release tablet, matrik, HPMC, Xanthan gum, Floating system.]]>
