Ro. Macedo et al., Comparison of generic hydrochlorothiazide formulations by means of TG and DSC coupled to a photovisual system, J THERM ANA, 64(2), 2001, pp. 757-763
The compatibilities and stabilities of some binary mixtures and generic hyd
rochlorothiazide formulations were studied by using TG, DSC and a DSC-photo
visual system. The kinetic parameters were determined via the Arrhenius equ
ations. Tablet B presented higher compatibility and thermal stability than
those of tablets A and C. The photovisual system demonstrated that the deco
mposition of tablet A occurs before the melting point, due to the Maillard
reaction between the hydrochlorothiazide and lactose present in the formula
tion. The behaviour and rate constants of binary mixtures suggest that lact
ose can be substituted for microcrystalline cellulose, MC(101), in tablet A
. The DSC and TG data revealed different characteristics of compatibility a
nd stability in generic formulations from different manufacturers.