34 patients suffering from detrusor hyperreflexia due to multiple sclerosis entered the trial and 32 patients accomplished. The patients received each drug for a period of 14 days. The patients made records of relevant symptoms, urgency and urge incontinence and compared the treatment periods according to these symptoms. Registration of the number of micturitions was also made. Furthermore, the patients underwent cystometric studies. The following parameters were recorded and compared: residual urine, volume at the first bladder contraction, effective volume and amplitude of the first bladder contraction. The study showed that the patients preferred methantheline bromide. The entire cystometric pattern changed statistically significant with methantheline bromide, but only with concordance to the patients preferences in 60%. Decrease in number of micturitions and volume at the first bladder contraction were the only parameters showing accordance with the preferences. The drugs caused many various side effects. 12 treatment periods were discontinued due to side effects of meladrazine tartrate. The cystometric recordings seem to be of little use in evaluation of a drugs therapeutic effect, and it is difficult to find parameters which reflect the patients preference of the drugs.