is melatonin a sedative
Our circadian rhythm (or âbody clockâ) is influenced by melatonin, as it acts as a âtime cueâ, anticipating sleep. It is also an important physiological regulator of the sleep-wake cycle. Melatonin is not a sedative, but a sign of darkness or night-time, and is a cue for innate night-time behaviour.In the morning when plasma levels of melatonin decrease, sleep ends and wakefulness begins.elatonin â A signal of darkness and marker for circadian rhythms. Melatonin is a naturally occurring hormone that is key to sleep and the sleep-wake cycle in humans and animals.