What is Nytol One-A-Night ? 50mg One-A-Night is a clinically proven sleep aid that can help relieve temporary sleeplessness & lull you into your regular sleep rhythm. Why should I choose Nytol One-A-Night ? Nytol One-A-Night may be a better solution for you if you’ve used sleeping aids in the past, or are looking for a convenient dosage as part of your bedtime routine. Simply taking a single tablet 20 minutes before bed can help you drift off towards the land of nod & restful sleep. How does Nytol One-A-Night work ? Let’s get a little sciencey for a second. That commonly used antihistamine we were talking about is diphenhydramine hydrochloride (trust us it’s easier to use than say). It blocks the normal actions of histamine, the chemical that stimulates arousal-promoting areas of the brain. This helps reduce alertness & promote that first drowsy stage of sleep. & once in that first stage of sleep, most people drift off naturally into restful deeper sleep.