Preparation and Evaluation of Solid Dispersions of Pilocarpine Hydrochloride for Alleviation of Xerostomia

This investigation was carried out to try the application of pilocarpine hydrochloride (PC) solid dispersion as sustained release dosage form. Four preparations of PC with ethylcellulose and/or hydroxypropylmethylcellulose phthalate were prepared by the organic solvent method. The preparation D including PC : ethylcellulose : hydroxypropylmethylcellulose phthalate (1 : 9 : 10 at weight ratio) showed the best sustained release behavior in dissolution test among four preparations. The preparation D was examined by powder X-ray diffractometry and differential scanning calorimetry, and confirmed to be solid dispersion. Saliva secretory effect of preparation D was examined in healthy male volunteers, and its effect for Xerostomia was showed.