Despite regular use of night-time zopiclone, frequently prescribed in combination with ‘as required’ alprazolam, amelioration of the nocturnal symptoms was not achieved. Postulated reasons for her altered sleep patterns included blindness and tolerance to benzodiazepine therapy. At a medication review meeting, the introduction of melatonin Inhibitors,research,lifescience,medical was proposed in an attempt to synchronize her wake—sleep cycle. Subsequently, melatonin in a controlled release formulation was commenced at a dose of 2 mg nightly. The immediate and sustained effects

on the patient have been remarkable. Significant improvements in daytime somnolence and a reduction in night-time awakening and calling have been achieved, with consequent

benefits to other residents. Medication requirements in terms of ‘as required’ alprazolam Inhibitors,research,lifescience,medical have been profoundly reduced and zopiclone has been discontinued. The beneficial effects on sundowning have been maintained 6 months post initiation of therapy. This is despite a license restriction to limit use to 3 weeks of therapy in patients aged 55 years of Inhibitors,research,lifescience,medical older, for the treatment of primary insomnia. At future reviews, further dose reduction of quetiapine therapy will be considered. The role of melatonin in controlling circadian rhythm is necessary for a normal wake—sleep pattern. Factors contributing to decreases in melatonin are diverse. The decrease in secretion of endogenous melatonin with aging is well documented [Olde Rikkert and Rigaud, 2001], and more profound reductions are reported in populations with dementia Inhibitors,research,lifescience,medical [Cardinali et al. 2006]. Benzodiazepines, which are widely used in the elderly population for the initiation of sleep, as in this patient, have also been reported to reduce melatonin production [Garfinkel et al. 1997]. A recent Cochrane review concluded, however, that there was insufficient evidence to support the effectiveness of melatonin in the management of cognitive and noncognitive sequelae of dementia [Jansen et al. 2006]. In the blind population

due to the absence of light cues, disturbances of circadian Inhibitors,research,lifescience,medical rhythms are common. These disturbances can result GBA3 in delays in circadian cycle timing by as much as 60–70 minutes per day [Sack et al. 2000]. Even if they try to sleep at regular times, they typically sleep well only a few days a month, when their Temozolomide mouse internal clocks fall in synchronization with preferred daily schedules. These chaotic free-running circadian rhythms have been successfully entrained with administration of exogenous melatonin resulting in appropriate phase shifts in sleep patterns [Sack et al. 2000]. The decision to commence melatonin in our patient was based primarily on the temporal relationship between blindness and wake—sleep dysrhythmias, but results seem to indicate a beneficial effect on more than just her sleep pattern.