Purpose <p>This study investigates the influence of blending muskmelon seed starch (MS) with microcrystalline cellulose (M) in different ratios on their functional behaviour and drug-release characteristics, including sustained-release performance, for pharmaceutical excipient applications.</p> Method <p>MS and M were combined in different proportions and evaluated for micromeritic analysis, physicochemical characterization, structural characterization, rheological properties and dissolution studies using paracetamol as a model drug.</p> Result <p>Increasing M concentration improved flowability, resulting in a 15% reduction in Hausner’s ratio compared to MS alone (<i>p</i> &lt; 0.05). The blends exhibited low ash content, near-neutral pH, and moisture levels below 8%. Swelling studies indicated that amorphous MS promoted disintegration, whereas crystalline M restricted excessive hydration. XRD showed increased crystallinity, supporting mechanical stability. The blends showed improved release behavior, with cumulative drug release after 6&#xa0;h exceeding 80% for MSM3, compared with &lt; 60% for MS and &lt; 40% for M (<i>p</i> &lt; 0.01). The sustained-release study corresponded to starch-cellulose interactions forming a viscous diffusion barrier. Rheological analysis confirmed pseudoplastic shear-thinning characteristics.</p> Conclusion <p>The findings indicate that MS-M blends function as multifunctional excipients exhibiting enhanced flow, swelling, and drug release with MSM3 showing the enhanced properties.</p>