Predisposing factors of urinary retention eg, spinal cord lesion, prostatic hyperplasia; patients w/ epilepsy or at risk of convulsion. Consider 3-day wash-out period before performing allergy skin tests. Avoid alcohol consumption. W/drawal syndrome. Not to be taken by patients w/ galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption. May affect ability to drive & use machines. Renal & hepatic impairment. Pregnancy & lactation. Elderly.