Abstract: Pharmaceutical compositions for the improvement of dysuria comprising a pharmaceutical carrier and a therapeutically effective amount of a xanthine derivative represented by the general formula I ##STR1## wherein R.sub.1 denotes a group of the formula R.sub.4 -CO- or R.sub.5 R.sub.6 (OH)C- or a carboxyl group, wherein R.sub.4 and R.sub.5 independently denote an alkyl group having 1-3 carbon atoms, and R.sub.6 denotes a hydrogen atom or an alkyl group having 1-3 carbon atoms, R.sub.2 denotes a hydrogen atom, an alkyl group having 1-5 carbon atoms or an alkyloxy group having 1-5 carbon atoms, R.sub.3 denotes an alkyl group having 1-3 carbon atoms and n denotes 1-6 or a pharmaceutically acceptable acid addition salt thereof.They are active in prolonging urination intervals and increasing urination threshold pressure with almost no influence upon constrictive force of the bladder. Thus, they are effective in treatment and prevention of dysuria such as pollakiuria and incontinence of urine.