Changes in the hardness, dissolution, and the disintegration time of brand name and generic preparations (6 preparations) of famotidine orally disintegrating tablets were investigated. Tablets had been stored in a thermo-hygrostat-controlled environment set to simulate the home conditions of patients up to 8 weeks after unit-dose packaging. Among the tablets in unit-dose packaging prepared immediately after blister packs (BP) were opened, one generic had decreased hardness to less than 2.0 kg after 1 week, 55.1% of its initial hardness value, and a shorter disintegration time of about 1/5 of its initial disintegration time. Generics met the standard for dissolution 8 weeks after unit-dose packaging. The decrease in hardness after unit-dose packaging is presumed to be associated with additives, and particularly the types and amounts of binding agents, but evidence of this association was lacking. The hardness noted in drug interview forms (IFs) and the state of sales of bulk tablet packages must be determined to facilitate the selection of generics that remain hard even after unit-dose packaging.