Tablets, hydrochlorothiazide

Characterization of the physical properties of excipients is also important. This is demonstrated in Table 2 in the light of the example of hydrochlorothiazide. Tablets of greater hardness are obtained if fine instead of coarse Povidone K 90 is taken. To a certain extent, the disintegration and the release are also affected. 

Influence of the particle size of Povidone K 90 on the properties of hydrochlorothiazide tablets (solvent granulation)... 

While particle size continues to be the physical property most frequently determined by NIR spectroscopy, several other parameters including the dissolution rate and the thickness and hardness of the ethylcellulose coating on theophylline tablets have also been determined using NIR, all with good errors of prediction.94 Tablet hardness, which dictates mechanical stability and dissolution rate, has been determined in hydrochlorothiazide tablets.95... 

Desai D, Rinaldi F, Kothari S, Panichuri S, Both D. Effect of hydroxypropyl cellulose (HPC) on dissolution rate of hydrochlorothiazide tablets. Int J Pharm 2006 308(1-2) 40-5. 

Fig. 41. Influence of 5% maltodextrine (Lycatab DSH) and povidone on the hardness of hydrochlorothiazide tablets [527].

Fig. 76. Influence of compression force on the hardness of hydrochlorothiazide tablets containing 5 % of disintegrant [390]...

In hydrochlorothiazid tablets almost all commercial types of crospovidone were compared using soluble and insoluble fillers [662]. In the case of dicalcium phosphate as filler the disintegration times and dissolution results of the active ingredient depend strongly on the type of crospovidone used. In the case of lactose as filler no significant difference between all crospovidone types could be seen in the disintegration time of the tablet and the dissolution rate of hydrochlorothiazide. 

SPIRONOLACTONE/HYDROCHLOROTHIAZIDE (Aldactazide tablets 25 mg spironolactone and 25 mg hydrochlorothiazide, tablets 50 mg spironolactone and 50 mg hydrochlorothiazide)... 

Moexipril and Hydrochlorothiazide Tablets. leva Pharmaceuticals USA. US Prescribing information, June 2004. 

Alam AS, Parrott EL. Effect of aging on some physical properties of hydrochlorothiazide tablets. J Pharm Sci 1971 60 263-266. 

Excipients used for lubrieation in tablet formulations can have an adverse effect on the dissolution eharacteristics of the final tablet. Hydrochlorothiazide tablets lubrieated with talc have been shown to have improved dissolution properties as eompared to similar tablets lubricated with magnesium stearate (Dawoodbhai et al, 1987). This same study also foimd talc to improve hardness, friability and appearance for some systems when compared to other lubrieants. It was additionally noted that different sources of talc showed signifieant variation in their glidant and lubricant efficiencies. 

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