urinary urgency has a significant association with other symptoms of OAB [5,6]. As urgency is the 'driving' symptom in OAB [7], those with OAB often experience urgency at inconvenient and unpredictable times, and consequently often lose control before reaching the toilet. This adversely affects their physical and psychological state by limiting daily activities, intimacy, compromising sexual function, and worsening self-esteem. It is no surprise therefore that patients often consider that improvements in urgency are the most noticeable response to therapy.Many areas of controversy surround the use of the term 'urgency' . Starting with terminology, how does urgency differ from 'urge' or 'the normal desire to void' (the latter in our view being a preferable term). It is a sensory symptom, and as such is difficult to define, to communicate to both patients and colleagues alike, and to measure and quantify, despite the additional variable introduced by inter-individual variation. Furthermore, when OAB has neurological causes, is the sensation different from that in people with idiopathic detrusor overactivity (IDO)?Where is the sensation located; in the suprapubic area or the perineum? Are there differences in the symptom of urgency and its clinical features in men compared to women? Certainly this would be expected to be the case, with a greater likelihood of an association with urgency incontinence and a shorter 'warning' or postponement time in women than men. Therefore it is no surprise that all attempts to quantify this symptom, in particular using warning time, have proved controversial and been of limited success. Clearly, despite the difficulties in its quantification, urgency and the other symptoms of OAB result in a significant deterioration in health-related quality of life (HRQoL) [8,9].To date, patient diaries have been a reliable way to collect OAB symptom data, including urgency episodes, nocturia, micturition and urgency incontinence episodes, and diary entry remains the most accurate and sensitive method for evaluating changes in urgency with pharmacotherapy. Data obtained on the basis of 3-or 4-day diaries suggest that short-duration diaries are just as reliable as those recorded for 7 days and, because they are less of a burden for patients, might be a more acceptable way to assess OAB symptoms [10].The concept of warning-time was introduced with the drug darifenacin, which was initially reported to increase warning-time by a median of 4.3 min compared with placebo [11]. However, the results in that pilot study are far from conclusive, and subsequent studies have failed to show a significant effect on warning-time [12].
WHICH CHOLINERGIC RECEPTOR?The detrusor smooth muscle is rich in cholinergic-muscarinic receptors. Electrical stimulation of an intact cholinergic nerve or application of a cholinergic agonist to a strip of detrusor muscle results in detrusor muscle contraction. All of the drugs approved to date for OAB work on the basis of blocking cholinergic receptors that stabilize the bladder ...