Theophylline salts, dissolution

The selection of a salt form directly influences the physicochemical and biopharmaceutical properties of a compound. The impact of salt selection has been reviewed. Nelson examined the dissolution of theophylline salts and commented on their impact on oral administration. The dissolution rates of the theophylline salts proceeded independently of the pH of the medium but was governed by the diffusion layer pH. The choline and isopropanolamine salts dissolved three to four times faster than the ethylenediamine salt and produced higher and prolonged blood levels. 

Serajuddin, A.T.M. Jarowski, C.I. Effect of diffusion layer 54. pH and solubility on the dissolution rate of pharmaceutical acids and their sodium salts. II. Salicylic acid, theophylline and benzoic acid. J. Pharm. Sci. 1985, 74 (2), 148-154. 55. 

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