The invention is a novel pillbox for storing medicines that overcomes the deficiencies in existing commercial products. Unlike existing products, in which medicine is loaded into the pillbox by opening a top lid, the present invention is a pillbox that allows side-loading and unloading, thereby eliminating the lids. Because the lids tend to break after extensive use, the elimination of the lids extends the lifetime of the pillbox. Another objective of the invention is to offer the user medicine compartments with sizes that can be easily modified, unlike existing products that only offer medicine compartments with fixed sizes.